コード例 #1
0
/*
 * Try to write data in the inode.
 * If the inode has inline data, check whether the new write can be
 * in the inode also. If not, create the page the handle, move the data
 * to the page make it update and let the later codes create extent for it.
 */
int ext4_try_to_write_inline_data(struct address_space *mapping,
				  struct inode *inode,
				  loff_t pos, unsigned len,
				  unsigned flags,
				  struct page **pagep)
{
	int ret;
	handle_t *handle;
	struct page *page;
	struct ext4_iloc iloc;

	if (pos + len > ext4_get_max_inline_size(inode))
		goto convert;

	ret = ext4_get_inode_loc(inode, &iloc);
	if (ret)
		return ret;

	/*
	 * The possible write could happen in the inode,
	 * so try to reserve the space in inode first.
	 */
	handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
	if (IS_ERR(handle)) {
		ret = PTR_ERR(handle);
		handle = NULL;
		goto out;
	}

	ret = ext4_prepare_inline_data(handle, inode, pos + len);
	if (ret && ret != -ENOSPC)
		goto out;

	/* We don't have space in inline inode, so convert it to extent. */
	if (ret == -ENOSPC) {
		ext4_journal_stop(handle);
		brelse(iloc.bh);
		goto convert;
	}

	flags |= AOP_FLAG_NOFS;

	page = grab_cache_page_write_begin(mapping, 0, flags);
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}

	*pagep = page;
	down_read(&EXT4_I(inode)->xattr_sem);
	if (!ext4_has_inline_data(inode)) {
		ret = 0;
		unlock_page(page);
		page_cache_release(page);
		goto out_up_read;
	}

	if (!PageUptodate(page)) {
		ret = ext4_read_inline_page(inode, page);
		if (ret < 0)
			goto out_up_read;
	}

	ret = 1;
	handle = NULL;
out_up_read:
	up_read(&EXT4_I(inode)->xattr_sem);
out:
	if (handle)
		ext4_journal_stop(handle);
	brelse(iloc.bh);
	return ret;
convert:
	return ext4_convert_inline_data_to_extent(mapping,
						  inode, flags);
}
コード例 #2
0
static int gfs2_write_begin(struct file *file, struct address_space *mapping,
			    loff_t pos, unsigned len, unsigned flags,
			    struct page **pagep, void **fsdata)
{
	struct gfs2_inode *ip = GFS2_I(mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	int alloc_required;
	int error = 0;
	struct gfs2_alloc *al = NULL;
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	unsigned from = pos & (PAGE_CACHE_SIZE - 1);
	unsigned to = from + len;
	struct page *page;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
	error = gfs2_glock_nq(&ip->i_gh);
	if (unlikely(error))
		goto out_uninit;
	if (&ip->i_inode == sdp->sd_rindex) {
		error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
					   GL_NOCACHE, &m_ip->i_gh);
		if (unlikely(error)) {
			gfs2_glock_dq(&ip->i_gh);
			goto out_uninit;
		}
	}

	alloc_required = gfs2_write_alloc_required(ip, pos, len);

	if (alloc_required || gfs2_is_jdata(ip))
		gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);

	if (alloc_required) {
		al = gfs2_alloc_get(ip);
		if (!al) {
			error = -ENOMEM;
			goto out_unlock;
		}

		error = gfs2_quota_lock_check(ip);
		if (error)
			goto out_alloc_put;

		al->al_requested = data_blocks + ind_blocks;
		error = gfs2_inplace_reserve(ip);
		if (error)
			goto out_qunlock;
	}

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;
	if (&ip->i_inode == sdp->sd_rindex)
		rblocks += 2 * RES_STATFS;
	if (alloc_required)
		rblocks += gfs2_rg_blocks(al);

	error = gfs2_trans_begin(sdp, rblocks,
				 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
	if (error)
		goto out_trans_fail;

	error = -ENOMEM;
	flags |= AOP_FLAG_NOFS;
	page = grab_cache_page_write_begin(mapping, index, flags);
	*pagep = page;
	if (unlikely(!page))
		goto out_endtrans;

	if (gfs2_is_stuffed(ip)) {
		error = 0;
		if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
			error = gfs2_unstuff_dinode(ip, page);
			if (error == 0)
				goto prepare_write;
		} else if (!PageUptodate(page)) {
			error = stuffed_readpage(ip, page);
		}
		goto out;
	}

prepare_write:
	error = block_prepare_write(page, from, to, gfs2_block_map);
out:
	if (error == 0)
		return 0;

	page_cache_release(page);

	gfs2_trans_end(sdp);
	if (pos + len > ip->i_inode.i_size)
		gfs2_trim_blocks(&ip->i_inode);
	goto out_trans_fail;

out_endtrans:
	gfs2_trans_end(sdp);
out_trans_fail:
	if (alloc_required) {
		gfs2_inplace_release(ip);
out_qunlock:
		gfs2_quota_unlock(ip);
out_alloc_put:
		gfs2_alloc_put(ip);
	}
out_unlock:
	if (&ip->i_inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_gh);
	return error;
}
コード例 #3
0
ファイル: data.c プロジェクト: aejsmith/linux
static int f2fs_write_begin(struct file *file, struct address_space *mapping,
                            loff_t pos, unsigned len, unsigned flags,
                            struct page **pagep, void **fsdata)
{
    struct inode *inode = mapping->host;
    struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
    struct page *page = NULL;
    struct page *ipage;
    pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
    struct dnode_of_data dn;
    int err = 0;

    trace_f2fs_write_begin(inode, pos, len, flags);

    f2fs_balance_fs(sbi);

    /*
     * We should check this at this moment to avoid deadlock on inode page
     * and #0 page. The locking rule for inline_data conversion should be:
     * lock_page(page #0) -> lock_page(inode_page)
     */
    if (index != 0) {
        err = f2fs_convert_inline_inode(inode);
        if (err)
            goto fail;
    }
repeat:
    page = grab_cache_page_write_begin(mapping, index, flags);
    if (!page) {
        err = -ENOMEM;
        goto fail;
    }

    *pagep = page;

    f2fs_lock_op(sbi);

    /* check inline_data */
    ipage = get_node_page(sbi, inode->i_ino);
    if (IS_ERR(ipage)) {
        err = PTR_ERR(ipage);
        goto unlock_fail;
    }

    set_new_dnode(&dn, inode, ipage, ipage, 0);

    if (f2fs_has_inline_data(inode)) {
        if (pos + len <= MAX_INLINE_DATA) {
            read_inline_data(page, ipage);
            set_inode_flag(F2FS_I(inode), FI_DATA_EXIST);
            sync_inode_page(&dn);
            goto put_next;
        }
        err = f2fs_convert_inline_page(&dn, page);
        if (err)
            goto put_fail;
    }

    err = f2fs_get_block(&dn, index);
    if (err)
        goto put_fail;
put_next:
    f2fs_put_dnode(&dn);
    f2fs_unlock_op(sbi);

    f2fs_wait_on_page_writeback(page, DATA);

    if (len == PAGE_CACHE_SIZE)
        goto out_update;
    if (PageUptodate(page))
        goto out_clear;

    if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
        unsigned start = pos & (PAGE_CACHE_SIZE - 1);
        unsigned end = start + len;

        /* Reading beyond i_size is simple: memset to zero */
        zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
        goto out_update;
    }

    if (dn.data_blkaddr == NEW_ADDR) {
        zero_user_segment(page, 0, PAGE_CACHE_SIZE);
    } else {
        struct f2fs_io_info fio = {
            .sbi = sbi,
            .type = DATA,
            .rw = READ_SYNC,
            .blk_addr = dn.data_blkaddr,
            .page = page,
            .encrypted_page = NULL,
        };
        err = f2fs_submit_page_bio(&fio);
        if (err)
            goto fail;

        lock_page(page);
        if (unlikely(!PageUptodate(page))) {
            err = -EIO;
            goto fail;
        }
        if (unlikely(page->mapping != mapping)) {
            f2fs_put_page(page, 1);
            goto repeat;
        }

        /* avoid symlink page */
        if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
            err = f2fs_decrypt_one(inode, page);
            if (err)
                goto fail;
        }
    }
out_update:
    SetPageUptodate(page);
out_clear:
    clear_cold_data(page);
    return 0;

put_fail:
    f2fs_put_dnode(&dn);
unlock_fail:
    f2fs_unlock_op(sbi);
fail:
    f2fs_put_page(page, 1);
    f2fs_write_failed(mapping, pos + len);
    return err;
}

static int f2fs_write_end(struct file *file,
                          struct address_space *mapping,
                          loff_t pos, unsigned len, unsigned copied,
                          struct page *page, void *fsdata)
{
    struct inode *inode = page->mapping->host;

    trace_f2fs_write_end(inode, pos, len, copied);

    set_page_dirty(page);

    if (pos + copied > i_size_read(inode)) {
        i_size_write(inode, pos + copied);
        mark_inode_dirty(inode);
        update_inode_page(inode);
    }

    f2fs_put_page(page, 1);
    return copied;
}

static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
                           loff_t offset)
{
    unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;

    if (offset & blocksize_mask)
        return -EINVAL;

    if (iov_iter_alignment(iter) & blocksize_mask)
        return -EINVAL;

    return 0;
}
コード例 #4
0
ファイル: file.c プロジェクト: A2109devs/lenovo_a2109a_kernel
static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	unsigned long last_index;
	u64 pos = page->index << PAGE_CACHE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	int alloc_required = 0;
	struct gfs2_holder gh;
	struct gfs2_alloc *al;
	int ret;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out;

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
	if (ret || !alloc_required)
		goto out_unlock;
	ret = -ENOMEM;
	al = gfs2_alloc_get(ip);
	if (al == NULL)
		goto out_unlock;

	ret = gfs2_quota_lock_check(ip);
	if (ret)
		goto out_alloc_put;
	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
	al->al_requested = data_blocks + ind_blocks;
	ret = gfs2_inplace_reserve(ip);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT;
	if (page->index > last_index)
		goto out_unlock_page;
	ret = 0;
	if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping)
		goto out_unlock_page;
	if (gfs2_is_stuffed(ip)) {
		ret = gfs2_unstuff_dinode(ip, page);
		if (ret)
			goto out_unlock_page;
	}
	ret = gfs2_allocate_page_backing(page);

out_unlock_page:
	unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_alloc_put:
	gfs2_alloc_put(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out:
	gfs2_holder_uninit(&gh);
	if (ret == -ENOMEM)
		ret = VM_FAULT_OOM;
	else if (ret)
		ret = VM_FAULT_SIGBUS;
	return ret;
}
コード例 #5
0
ファイル: microfs_read.c プロジェクト: edlund/linux-microfs
int __microfs_readpage(struct file* file, struct page* page)
{
	struct inode* inode = page->mapping->host;
	struct super_block* sb = inode->i_sb;
	struct microfs_sb_info* sbi = MICROFS_SB(sb);
	
	int err = 0;
	int small_blks = sbi->si_blksz <= PAGE_SIZE;
	
	__u32 i;
	__u32 j;
	
	__u32 data_offset = 0;
	__u32 data_length = 0;
	__u32 blk_data_offset = 0;
	__u32 blk_data_length = 0;
	
	__u32 pgholes = 0;
	
	__u32 blk_ptrs = i_blks(i_size_read(inode), sbi->si_blksz);
	__u32 blk_nr = small_blks
		? page->index * (PAGE_SIZE >> sbi->si_blkshift)
		: page->index / (sbi->si_blksz / PAGE_SIZE);
	
	int index_mask = small_blks
		? 0
		: (1 << (sbi->si_blkshift - PAGE_SHIFT)) - 1;
	
	__u32 max_index = i_blks(i_size_read(inode), PAGE_SIZE);
	__u32 start_index = (small_blks ? page->index : page->index & ~index_mask);
	__u32 end_index = (small_blks ? page->index : start_index | index_mask) + 1;
	
	struct microfs_readpage_request rdreq;
	
	if (end_index > max_index)
		end_index = max_index;
	
	pr_spam("__microfs_readpage: sbi->si_blksz=%u, blk_ptrs=%u, blk_nr=%u\n",
		sbi->si_blksz, blk_ptrs, blk_nr);
	pr_spam("__microfs_readpage: start_index=%u, end_index=%u, max_index=%u\n",
		start_index, end_index, max_index);
	
	mutex_lock(&sbi->si_metadata_blkptrbuf.d_mutex);
	for (i = 0; (data_length < PAGE_SIZE && blk_nr + i < blk_ptrs) &&
			(i == 0 || sbi->si_blksz < PAGE_SIZE); ++i) {
		err = __microfs_find_block(sb, inode, blk_ptrs, blk_nr + i,
			&blk_data_offset, &blk_data_length);
		if (unlikely(err)) {
			mutex_unlock(&sbi->si_metadata_blkptrbuf.d_mutex);
			goto err_find_block;
		}
		if (!data_offset)
			data_offset = blk_data_offset;
		data_length += blk_data_length;
	}
	mutex_unlock(&sbi->si_metadata_blkptrbuf.d_mutex);
	
	pr_spam("__microfs_readpage: data_offset=0x%x, data_length=%u\n",
		data_offset, data_length);
	
	rdreq.rr_bhoffset = data_offset - (data_offset & PAGE_MASK);
	rdreq.rr_npages = end_index - start_index;
	rdreq.rr_pages = kmalloc(rdreq.rr_npages * sizeof(void*), GFP_KERNEL);
	if (!rdreq.rr_pages) {
		pr_err("__microfs_readpage: failed to allocate rdreq.rr_pages (%u slots)\n",
			rdreq.rr_npages);
		err = -ENOMEM;
		goto err_mem;
	}
	
	pr_spam("__microfs_readpage: rdreq.rr_pages=0x%p, rdreq.rr_npages=%u\n",
		rdreq.rr_pages, rdreq.rr_npages);
	
	for (i = 0, j = start_index; j < end_index; ++i, ++j) {
		rdreq.rr_pages[i] = (j == page->index)
			? page
			: grab_cache_page_nowait(page->mapping, j);
		if (rdreq.rr_pages[i] == page) {
			pr_spam("__microfs_readpage: target page 0x%p at index %u\n",
				page, j);
		} else if (rdreq.rr_pages[i] == NULL) {
			pgholes++;
			pr_spam("__microfs_readpage: busy page at index %u\n", j);
		} else if (PageUptodate(rdreq.rr_pages[i])) {
			unlock_page(rdreq.rr_pages[i]);
			put_page(rdreq.rr_pages[i]);
			rdreq.rr_pages[i] = NULL;
			pgholes++;
			pr_spam("__microfs_readpage: page up to date at index %u\n", j);
		} else {
			pr_spam("__microfs_readpage: new page 0x%p added for index %u\n",
				rdreq.rr_pages[i], j);
		}
	}
	
	pr_spam("__microfs_readpage: pgholes=%u\n", pgholes);
	
	if (pgholes) {
		/* It seems that one or more pages have been reclaimed, but
		 * it is also possible that another thread is trying to read
		 * the same data.
		 */
		err = __microfs_read_blks(sb, page->mapping, &rdreq,
			__microfs_recycle_filedata_exceptionally,
			__microfs_copy_filedata_exceptionally,
			data_offset, data_length);
	} else {
		/* It is possible to uncompress the file data directly into
		 * the page cache. Neat.
		 */
		err = __microfs_read_blks(sb, page->mapping, &rdreq,
			__microfs_recycle_filedata_nominally,
			__microfs_copy_filedata_nominally,
			data_offset, data_length);
	}
	if (unlikely(err)) {
		pr_err("__microfs_readpage: __microfs_read_blks failed\n");
		goto err_io;
	}
	
	for (i = 0; i < rdreq.rr_npages; ++i) {
		if (rdreq.rr_pages[i]) {
			flush_dcache_page(rdreq.rr_pages[i]);
			SetPageUptodate(rdreq.rr_pages[i]);
			unlock_page(rdreq.rr_pages[i]);
			if (rdreq.rr_pages[i] != page)
				put_page(rdreq.rr_pages[i]);
		}
	}
	
	kfree(rdreq.rr_pages);
	
	return 0;
	
err_io:
	pr_spam("__microfs_readpage: failure\n");
	for (i = 0; i < rdreq.rr_npages; ++i) {
		if (rdreq.rr_pages[i]) {
			flush_dcache_page(rdreq.rr_pages[i]);
			SetPageError(rdreq.rr_pages[i]);
			unlock_page(rdreq.rr_pages[i]);
			if (rdreq.rr_pages[i] != page)
				put_page(rdreq.rr_pages[i]);
		}
	}
	kfree(rdreq.rr_pages);
err_mem:
	/* Fall-trough. */
err_find_block:
	return err;
}
コード例 #6
0
static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	unsigned long last_index;
	u64 pos = page->index << PAGE_CACHE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	struct gfs2_holder gh;
	loff_t size;
	int ret;

	sb_start_pagefault(inode->i_sb);

	/* Update file times before taking page lock */
	file_update_time(vma->vm_file);

	ret = gfs2_rs_alloc(ip);
	if (ret)
		return ret;

	gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out;

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) {
		lock_page(page);
		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
			ret = -EAGAIN;
			unlock_page(page);
		}
		goto out_unlock;
	}

	ret = gfs2_rindex_update(sdp);
	if (ret)
		goto out_unlock;

	ret = gfs2_quota_lock_check(ip);
	if (ret)
		goto out_unlock;
	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
	ret = gfs2_inplace_reserve(ip, data_blocks + ind_blocks, 0);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks) {
		rblocks += RES_STATFS + RES_QUOTA;
		rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
	}
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	size = i_size_read(inode);
	last_index = (size - 1) >> PAGE_CACHE_SHIFT;
	/* Check page index against inode size */
	if (size == 0 || (page->index > last_index))
		goto out_trans_end;

	ret = -EAGAIN;
	/* If truncated, we must retry the operation, we may have raced
	 * with the glock demotion code.
	 */
	if (!PageUptodate(page) || page->mapping != inode->i_mapping)
		goto out_trans_end;

	/* Unstuff, if required, and allocate backing blocks for page */
	ret = 0;
	if (gfs2_is_stuffed(ip))
		ret = gfs2_unstuff_dinode(ip, page);
	if (ret == 0)
		ret = gfs2_allocate_page_backing(page);

out_trans_end:
	if (ret)
		unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out:
	gfs2_holder_uninit(&gh);
	if (ret == 0) {
		set_page_dirty(page);
		wait_on_page_writeback(page);
	}
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}
コード例 #7
0
ファイル: file.c プロジェクト: CSCLOG/beaglebone
static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
                             loff_t pos, unsigned len, unsigned flags,
                             struct page **pagep, void **fsdata)
{
    struct page *pg;
    struct inode *inode = mapping->host;
    struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
    pgoff_t index = pos >> PAGE_CACHE_SHIFT;
    uint32_t pageofs = index << PAGE_CACHE_SHIFT;
    int ret = 0;

    pg = grab_cache_page_write_begin(mapping, index, flags);
    if (!pg)
        return -ENOMEM;
    *pagep = pg;

    D1(printk(KERN_DEBUG "jffs2_write_begin()\n"));

    if (pageofs > inode->i_size) {
        /* Make new hole frag from old EOF to new page */
        struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
        struct jffs2_raw_inode ri;
        struct jffs2_full_dnode *fn;
        uint32_t alloc_len;

        D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
                  (unsigned int)inode->i_size, pageofs));

        ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
                                  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
        if (ret)
            goto out_page;

        mutex_lock(&f->sem);
        memset(&ri, 0, sizeof(ri));

        ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
        ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
        ri.totlen = cpu_to_je32(sizeof(ri));
        ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));

        ri.ino = cpu_to_je32(f->inocache->ino);
        ri.version = cpu_to_je32(++f->highest_version);
        ri.mode = cpu_to_jemode(inode->i_mode);
        ri.uid = cpu_to_je16(inode->i_uid);
        ri.gid = cpu_to_je16(inode->i_gid);
        ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
        ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
        ri.offset = cpu_to_je32(inode->i_size);
        ri.dsize = cpu_to_je32(pageofs - inode->i_size);
        ri.csize = cpu_to_je32(0);
        ri.compr = JFFS2_COMPR_ZERO;
        ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
        ri.data_crc = cpu_to_je32(0);

        fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);

        if (IS_ERR(fn)) {
            ret = PTR_ERR(fn);
            jffs2_complete_reservation(c);
            mutex_unlock(&f->sem);
            goto out_page;
        }
        ret = jffs2_add_full_dnode_to_inode(c, f, fn);
        if (f->metadata) {
            jffs2_mark_node_obsolete(c, f->metadata->raw);
            jffs2_free_full_dnode(f->metadata);
            f->metadata = NULL;
        }
        if (ret) {
            D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret));
            jffs2_mark_node_obsolete(c, fn->raw);
            jffs2_free_full_dnode(fn);
            jffs2_complete_reservation(c);
            mutex_unlock(&f->sem);
            goto out_page;
        }
        jffs2_complete_reservation(c);
        inode->i_size = pageofs;
        mutex_unlock(&f->sem);
    }

    /*
     * Read in the page if it wasn't already present. Cannot optimize away
     * the whole page write case until jffs2_write_end can handle the
     * case of a short-copy.
     */
    if (!PageUptodate(pg)) {
        mutex_lock(&f->sem);
        ret = jffs2_do_readpage_nolock(inode, pg);
        mutex_unlock(&f->sem);
        if (ret)
            goto out_page;
    }
    D1(printk(KERN_DEBUG "end write_begin(). pg->flags %lx\n", pg->flags));
    return ret;

out_page:
    unlock_page(pg);
    page_cache_release(pg);
    return ret;
}
コード例 #8
0
ファイル: splice.c プロジェクト: Voskrese/mipsonqemu
/*
 * This is a little more tricky than the file -> pipe splicing. There are
 * basically three cases:
 *
 *	- Destination page already exists in the address space and there
 *	  are users of it. For that case we have no other option that
 *	  copying the data. Tough luck.
 *	- Destination page already exists in the address space, but there
 *	  are no users of it. Make sure it's uptodate, then drop it. Fall
 *	  through to last case.
 *	- Destination page does not exist, we can add the pipe page to
 *	  the page cache and avoid the copy.
 *
 * If asked to move pages to the output file (SPLICE_F_MOVE is set in
 * sd->flags), we attempt to migrate pages from the pipe to the output
 * file address space page cache. This is possible if no one else has
 * the pipe page referenced outside of the pipe and page cache. If
 * SPLICE_F_MOVE isn't set, or we cannot move the page, we simply create
 * a new page in the output file page cache and fill/dirty that.
 */
static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
			struct splice_desc *sd)
{
	struct file *file = sd->file;
	struct address_space *mapping = file->f_mapping;
	unsigned int offset, this_len;
	struct page *page;
	pgoff_t index;
	int ret;

	/*
	 * make sure the data in this buffer is uptodate
	 */
	ret = buf->ops->pin(pipe, buf);
	if (unlikely(ret))
		return ret;

	index = sd->pos >> PAGE_CACHE_SHIFT;
	offset = sd->pos & ~PAGE_CACHE_MASK;

	this_len = sd->len;
	if (this_len + offset > PAGE_CACHE_SIZE)
		this_len = PAGE_CACHE_SIZE - offset;

	/*
	 * Reuse buf page, if SPLICE_F_MOVE is set and we are doing a full
	 * page.
	 */
	if ((sd->flags & SPLICE_F_MOVE) && this_len == PAGE_CACHE_SIZE) {
		/*
		 * If steal succeeds, buf->page is now pruned from the
		 * pagecache and we can reuse it. The page will also be
		 * locked on successful return.
		 */
		if (buf->ops->steal(pipe, buf))
			goto find_page;

		page = buf->page;
		if (add_to_page_cache(page, mapping, index, GFP_KERNEL)) {
			unlock_page(page);
			goto find_page;
		}

		page_cache_get(page);

		if (!(buf->flags & PIPE_BUF_FLAG_LRU))
			lru_cache_add(page);
	} else {
find_page:
		page = find_lock_page(mapping, index);
		if (!page) {
			ret = -ENOMEM;
			page = page_cache_alloc_cold(mapping);
			if (unlikely(!page))
				goto out_ret;

			/*
			 * This will also lock the page
			 */
			ret = add_to_page_cache_lru(page, mapping, index,
						    GFP_KERNEL);
			if (unlikely(ret))
				goto out;
		}

		/*
		 * We get here with the page locked. If the page is also
		 * uptodate, we don't need to do more. If it isn't, we
		 * may need to bring it in if we are not going to overwrite
		 * the full page.
		 */
		if (!PageUptodate(page)) {
			if (this_len < PAGE_CACHE_SIZE) {
				ret = mapping->a_ops->readpage(file, page);
				if (unlikely(ret))
					goto out;

				lock_page(page);

				if (!PageUptodate(page)) {
					/*
					 * Page got invalidated, repeat.
					 */
					if (!page->mapping) {
						unlock_page(page);
						page_cache_release(page);
						goto find_page;
					}
					ret = -EIO;
					goto out;
				}
			} else
				SetPageUptodate(page);
		}
	}

	ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
	if (unlikely(ret)) {
		loff_t isize = i_size_read(mapping->host);

		if (ret != AOP_TRUNCATED_PAGE)
			unlock_page(page);
		page_cache_release(page);
		if (ret == AOP_TRUNCATED_PAGE)
			goto find_page;

		/*
		 * prepare_write() may have instantiated a few blocks
		 * outside i_size.  Trim these off again.
		 */
		if (sd->pos + this_len > isize)
			vmtruncate(mapping->host, isize);

		goto out_ret;
	}

	if (buf->page != page) {
		/*
		 * Careful, ->map() uses KM_USER0!
		 */
		char *src = buf->ops->map(pipe, buf, 1);
		char *dst = kmap_atomic(page, KM_USER1);

		memcpy(dst + offset, src + buf->offset, this_len);
		flush_dcache_page(page);
		kunmap_atomic(dst, KM_USER1);
		buf->ops->unmap(pipe, buf, src);
	}

	ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);
	if (!ret) {
		/*
		 * Return the number of bytes written and mark page as
		 * accessed, we are now done!
		 */
		ret = this_len;
		mark_page_accessed(page);
		balance_dirty_pages_ratelimited(mapping);
	} else if (ret == AOP_TRUNCATED_PAGE) {
		page_cache_release(page);
		goto find_page;
	}
out:
	page_cache_release(page);
	unlock_page(page);
out_ret:
	return ret;
}
コード例 #9
0
ファイル: splice.c プロジェクト: xf739645524/kernel-rhel5
static int
__generic_file_splice_read(struct file *in, loff_t *ppos,
			   struct pipe_inode_info *pipe, size_t len,
			   unsigned int flags)
{
	struct address_space *mapping = in->f_mapping;
	unsigned int loff, nr_pages;
	struct page *pages[PIPE_BUFFERS];
	struct partial_page partial[PIPE_BUFFERS];
	struct page *page;
	pgoff_t index, end_index;
	loff_t isize;
	size_t total_len;
	int error, page_nr;
	struct splice_pipe_desc spd = {
		.pages = pages,
		.partial = partial,
		.flags = flags,
		.ops = &page_cache_pipe_buf_ops,
	};

	index = *ppos >> PAGE_CACHE_SHIFT;
	loff = *ppos & ~PAGE_CACHE_MASK;
	nr_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;

	if (nr_pages > PIPE_BUFFERS)
		nr_pages = PIPE_BUFFERS;

	/*
	 * Initiate read-ahead on this page range. however, don't call into
	 * read-ahead if this is a non-zero offset (we are likely doing small
	 * chunk splice and the page is already there) for a single page.
	 */
	if (!loff || nr_pages > 1)
		page_cache_readahead(mapping, &in->f_ra, in, index, nr_pages);

	/*
	 * Now fill in the holes:
	 */
	error = 0;
	total_len = 0;

	/*
	 * Lookup the (hopefully) full range of pages we need.
	 */
	spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, pages);

	/*
	 * If find_get_pages_contig() returned fewer pages than we needed,
	 * allocate the rest.
	 */
	index += spd.nr_pages;
	while (spd.nr_pages < nr_pages) {
		/*
		 * Page could be there, find_get_pages_contig() breaks on
		 * the first hole.
		 */
		page = find_get_page(mapping, index);
		if (!page) {
			/*
			 * Make sure the read-ahead engine is notified
			 * about this failure.
			 */
			handle_ra_miss(mapping, &in->f_ra, index);

			/*
			 * page didn't exist, allocate one.
			 */
			page = page_cache_alloc_cold(mapping);
			if (!page)
				break;

			error = add_to_page_cache_lru(page, mapping, index,
					      GFP_KERNEL);
			if (unlikely(error)) {
				page_cache_release(page);
				if (error == -EEXIST)
					continue;
				break;
			}
			/*
			 * add_to_page_cache() locks the page, unlock it
			 * to avoid convoluting the logic below even more.
			 */
			unlock_page(page);
		}

		pages[spd.nr_pages++] = page;
		index++;
	}

	/*
	 * Now loop over the map and see if we need to start IO on any
	 * pages, fill in the partial map, etc.
	 */
	index = *ppos >> PAGE_CACHE_SHIFT;
	nr_pages = spd.nr_pages;
	spd.nr_pages = 0;
	for (page_nr = 0; page_nr < nr_pages; page_nr++) {
		unsigned int this_len;

		if (!len)
			break;

		/*
		 * this_len is the max we'll use from this page
		 */
		this_len = min_t(unsigned long, len, PAGE_CACHE_SIZE - loff);
		page = pages[page_nr];

		/*
		 * If the page isn't uptodate, we may need to start io on it
		 */
		if (!PageUptodate(page)) {
			/*
			 * If in nonblock mode then dont block on waiting
			 * for an in-flight io page
			 */
			if (flags & SPLICE_F_NONBLOCK)
				break;

			lock_page(page);

			/*
			 * page was truncated, stop here. if this isn't the
			 * first page, we'll just complete what we already
			 * added
			 */
			if (!page->mapping) {
				unlock_page(page);
				break;
			}
			/*
			 * page was already under io and is now done, great
			 */
			if (PageUptodate(page)) {
				unlock_page(page);
				goto fill_it;
			}

			/*
			 * need to read in the page
			 */
			error = mapping->a_ops->readpage(in, page);
			if (unlikely(error)) {
				/*
				 * We really should re-lookup the page here,
				 * but it complicates things a lot. Instead
				 * lets just do what we already stored, and
				 * we'll get it the next time we are called.
				 */
				if (error == AOP_TRUNCATED_PAGE)
					error = 0;

				break;
			}

			/*
			 * i_size must be checked after ->readpage().
			 */
			isize = i_size_read(mapping->host);
			end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
			if (unlikely(!isize || index > end_index))
				break;

			/*
			 * if this is the last page, see if we need to shrink
			 * the length and stop
			 */
			if (end_index == index) {
				loff = PAGE_CACHE_SIZE - (isize & ~PAGE_CACHE_MASK);
				if (total_len + loff > isize)
					break;
				/*
				 * force quit after adding this page
				 */
				len = this_len;
				this_len = min(this_len, loff);
				loff = 0;
			}
		}
fill_it:
		partial[page_nr].offset = loff;
		partial[page_nr].len = this_len;
		len -= this_len;
		total_len += this_len;
		loff = 0;
		spd.nr_pages++;
		index++;
	}

	/*
	 * Release any pages at the end, if we quit early. 'i' is how far
	 * we got, 'nr_pages' is how many pages are in the map.
	 */
	while (page_nr < nr_pages)
		page_cache_release(pages[page_nr++]);

	if (spd.nr_pages)
		return splice_to_pipe(pipe, &spd);

	return error;
}
コード例 #10
0
ファイル: file.c プロジェクト: BackupTheBerlios/wl530g-svn
int jffs2_prepare_write (struct file *filp, struct page *pg, unsigned start, unsigned end)
{
	struct inode *inode = pg->mapping->host;
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT;
	int ret = 0;

	D1(printk(KERN_DEBUG "jffs2_prepare_write()\n"));

	if (pageofs > inode->i_size) {
		/* Make new hole frag from old EOF to new page */
		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
		struct jffs2_raw_inode ri;
		struct jffs2_full_dnode *fn;
		uint32_t phys_ofs, alloc_len;
		
		D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
			  (unsigned int)inode->i_size, pageofs));

		ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);
		if (ret)
			return ret;

		down(&f->sem);
		memset(&ri, 0, sizeof(ri));

		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
		ri.totlen = cpu_to_je32(sizeof(ri));
		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));

		ri.ino = cpu_to_je32(f->inocache->ino);
		ri.version = cpu_to_je32(++f->highest_version);
		ri.mode = cpu_to_jemode(inode->i_mode);
		ri.uid = cpu_to_je16(inode->i_uid);
		ri.gid = cpu_to_je16(inode->i_gid);
		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
		ri.offset = cpu_to_je32(inode->i_size);
		ri.dsize = cpu_to_je32(pageofs - inode->i_size);
		ri.csize = cpu_to_je32(0);
		ri.compr = JFFS2_COMPR_ZERO;
		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
		ri.data_crc = cpu_to_je32(0);
		
		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL);

		if (IS_ERR(fn)) {
			ret = PTR_ERR(fn);
			jffs2_complete_reservation(c);
			up(&f->sem);
			return ret;
		}
		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
		if (f->metadata) {
			jffs2_mark_node_obsolete(c, f->metadata->raw);
			jffs2_free_full_dnode(f->metadata);
			f->metadata = NULL;
		}
		if (ret) {
			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));
			jffs2_mark_node_obsolete(c, fn->raw);
			jffs2_free_full_dnode(fn);
			jffs2_complete_reservation(c);
			up(&f->sem);
			return ret;
		}
		jffs2_complete_reservation(c);
		inode->i_size = pageofs;
		up(&f->sem);
	}
	
	/* Read in the page if it wasn't already present, unless it's a whole page */
	if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) {
		down(&f->sem);
		ret = jffs2_do_readpage_nolock(inode, pg);
		up(&f->sem);
	}
	D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags));
	return ret;
}
コード例 #11
0
ファイル: aops.c プロジェクト: a2hojsjsjs/linux
static int gfs2_write_begin(struct file *file, struct address_space *mapping,
			    loff_t pos, unsigned len, unsigned flags,
			    struct page **pagep, void **fsdata)
{
	struct gfs2_inode *ip = GFS2_I(mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	unsigned requested = 0;
	int alloc_required;
	int error = 0;
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	unsigned from = pos & (PAGE_CACHE_SIZE - 1);
	struct page *page;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
	error = gfs2_glock_nq(&ip->i_gh);
	if (unlikely(error))
		goto out_uninit;
	if (&ip->i_inode == sdp->sd_rindex) {
		error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
					   GL_NOCACHE, &m_ip->i_gh);
		if (unlikely(error)) {
			gfs2_glock_dq(&ip->i_gh);
			goto out_uninit;
		}
	}

	alloc_required = gfs2_write_alloc_required(ip, pos, len);

	if (alloc_required || gfs2_is_jdata(ip))
		gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);

	if (alloc_required) {
		struct gfs2_alloc_parms ap = { .aflags = 0, };
		requested = data_blocks + ind_blocks;
		ap.target = requested;
		error = gfs2_quota_lock_check(ip, &ap);
		if (error)
			goto out_unlock;

		error = gfs2_inplace_reserve(ip, &ap);
		if (error)
			goto out_qunlock;
	}

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;
	if (&ip->i_inode == sdp->sd_rindex)
		rblocks += 2 * RES_STATFS;
	if (alloc_required)
		rblocks += gfs2_rg_blocks(ip, requested);

	error = gfs2_trans_begin(sdp, rblocks,
				 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
	if (error)
		goto out_trans_fail;

	error = -ENOMEM;
	flags |= AOP_FLAG_NOFS;
	page = grab_cache_page_write_begin(mapping, index, flags);
	*pagep = page;
	if (unlikely(!page))
		goto out_endtrans;

	if (gfs2_is_stuffed(ip)) {
		error = 0;
		if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
			error = gfs2_unstuff_dinode(ip, page);
			if (error == 0)
				goto prepare_write;
		} else if (!PageUptodate(page)) {
			error = stuffed_readpage(ip, page);
		}
		goto out;
	}

prepare_write:
	error = __block_write_begin(page, from, len, gfs2_block_map);
out:
	if (error == 0)
		return 0;

	unlock_page(page);
	page_cache_release(page);

	gfs2_trans_end(sdp);
	if (pos + len > ip->i_inode.i_size)
		gfs2_trim_blocks(&ip->i_inode);
	goto out_trans_fail;

out_endtrans:
	gfs2_trans_end(sdp);
out_trans_fail:
	if (alloc_required) {
		gfs2_inplace_release(ip);
out_qunlock:
		gfs2_quota_unlock(ip);
	}
out_unlock:
	if (&ip->i_inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_gh);
	return error;
}

/**
 * adjust_fs_space - Adjusts the free space available due to gfs2_grow
 * @inode: the rindex inode
 */
static void adjust_fs_space(struct inode *inode)
{
	struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
	struct buffer_head *m_bh, *l_bh;
	u64 fs_total, new_free;

	/* Total up the file system space, according to the latest rindex. */
	fs_total = gfs2_ri_total(sdp);
	if (gfs2_meta_inode_buffer(m_ip, &m_bh) != 0)
		return;

	spin_lock(&sdp->sd_statfs_spin);
	gfs2_statfs_change_in(m_sc, m_bh->b_data +
			      sizeof(struct gfs2_dinode));
	if (fs_total > (m_sc->sc_total + l_sc->sc_total))
		new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
	else
		new_free = 0;
	spin_unlock(&sdp->sd_statfs_spin);
	fs_warn(sdp, "File system extended by %llu blocks.\n",
		(unsigned long long)new_free);
	gfs2_statfs_change(sdp, new_free, new_free, 0);

	if (gfs2_meta_inode_buffer(l_ip, &l_bh) != 0)
		goto out;
	update_statfs(sdp, m_bh, l_bh);
	brelse(l_bh);
out:
	brelse(m_bh);
}

/**
 * gfs2_stuffed_write_end - Write end for stuffed files
 * @inode: The inode
 * @dibh: The buffer_head containing the on-disk inode
 * @pos: The file position
 * @len: The length of the write
 * @copied: How much was actually copied by the VFS
 * @page: The page
 *
 * This copies the data from the page into the inode block after
 * the inode data structure itself.
 *
 * Returns: errno
 */
static int gfs2_stuffed_write_end(struct inode *inode, struct buffer_head *dibh,
				  loff_t pos, unsigned len, unsigned copied,
				  struct page *page)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	u64 to = pos + copied;
	void *kaddr;
	unsigned char *buf = dibh->b_data + sizeof(struct gfs2_dinode);

	BUG_ON((pos + len) > (dibh->b_size - sizeof(struct gfs2_dinode)));
	kaddr = kmap_atomic(page);
	memcpy(buf + pos, kaddr + pos, copied);
	memset(kaddr + pos + copied, 0, len - copied);
	flush_dcache_page(page);
	kunmap_atomic(kaddr);

	if (!PageUptodate(page))
		SetPageUptodate(page);
	unlock_page(page);
	page_cache_release(page);

	if (copied) {
		if (inode->i_size < to)
			i_size_write(inode, to);
		mark_inode_dirty(inode);
	}

	if (inode == sdp->sd_rindex) {
		adjust_fs_space(inode);
		sdp->sd_rindex_uptodate = 0;
	}

	brelse(dibh);
	gfs2_trans_end(sdp);
	if (inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
	gfs2_holder_uninit(&ip->i_gh);
	return copied;
}

/**
 * gfs2_write_end
 * @file: The file to write to
 * @mapping: The address space to write to
 * @pos: The file position
 * @len: The length of the data
 * @copied: How much was actually copied by the VFS
 * @page: The page that has been written
 * @fsdata: The fsdata (unused in GFS2)
 *
 * The main write_end function for GFS2. We have a separate one for
 * stuffed files as they are slightly different, otherwise we just
 * put our locking around the VFS provided functions.
 *
 * Returns: errno
 */

static int gfs2_write_end(struct file *file, struct address_space *mapping,
			  loff_t pos, unsigned len, unsigned copied,
			  struct page *page, void *fsdata)
{
	struct inode *inode = page->mapping->host;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct buffer_head *dibh;
	unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
	unsigned int to = from + len;
	int ret;
	struct gfs2_trans *tr = current->journal_info;
	BUG_ON(!tr);

	BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == NULL);

	ret = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(ret)) {
		unlock_page(page);
		page_cache_release(page);
		goto failed;
	}

	if (gfs2_is_stuffed(ip))
		return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);

	if (!gfs2_is_writeback(ip))
		gfs2_page_add_databufs(ip, page, from, to);

	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
	if (tr->tr_num_buf_new)
		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
	else
		gfs2_trans_add_meta(ip->i_gl, dibh);


	if (inode == sdp->sd_rindex) {
		adjust_fs_space(inode);
		sdp->sd_rindex_uptodate = 0;
	}

	brelse(dibh);
failed:
	gfs2_trans_end(sdp);
	gfs2_inplace_release(ip);
	if (ip->i_qadata && ip->i_qadata->qa_qd_num)
		gfs2_quota_unlock(ip);
	if (inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
	gfs2_holder_uninit(&ip->i_gh);
	return ret;
}

/**
 * gfs2_set_page_dirty - Page dirtying function
 * @page: The page to dirty
 *
 * Returns: 1 if it dirtyed the page, or 0 otherwise
 */
 
static int gfs2_set_page_dirty(struct page *page)
{
	SetPageChecked(page);
	return __set_page_dirty_buffers(page);
}
コード例 #12
0
ファイル: file.c プロジェクト: robcore/Alucard-Kernel-jfltexx
static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = vma->vm_file->f_dentry->d_inode;
	struct nilfs_transaction_info ti;
	int ret;

	if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
		return VM_FAULT_SIGBUS; /* -ENOSPC */

	lock_page(page);
	if (page->mapping != inode->i_mapping ||
	    page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) {
		unlock_page(page);
		return VM_FAULT_NOPAGE; /* make the VM retry the fault */
	}

	/*
	 * check to see if the page is mapped already (no holes)
	 */
	if (PageMappedToDisk(page))
		goto mapped;

	if (page_has_buffers(page)) {
		struct buffer_head *bh, *head;
		int fully_mapped = 1;

		bh = head = page_buffers(page);
		do {
			if (!buffer_mapped(bh)) {
				fully_mapped = 0;
				break;
			}
		} while (bh = bh->b_this_page, bh != head);

		if (fully_mapped) {
			SetPageMappedToDisk(page);
			goto mapped;
		}
	}
	unlock_page(page);

	/*
	 * fill hole blocks
	 */
	ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
	/* never returns -ENOMEM, but may return -ENOSPC */
	if (unlikely(ret))
		return VM_FAULT_SIGBUS;

	file_update_time(vma->vm_file);
	ret = block_page_mkwrite(vma, vmf, nilfs_get_block);
	if (ret != VM_FAULT_LOCKED) {
		nilfs_transaction_abort(inode->i_sb);
		return ret;
	}
	nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
	nilfs_transaction_commit(inode->i_sb);

 mapped:
	wait_for_stable_page(page);
 out:
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}
コード例 #13
0
int direct2indirect(struct reiserfs_transaction_handle *th, struct inode *inode,
		    struct treepath *path, struct buffer_head *unbh,
		    loff_t tail_offset)
{
	struct super_block *sb = inode->i_sb;
	struct buffer_head *up_to_date_bh;
	struct item_head *p_le_ih = PATH_PITEM_HEAD(path);
	unsigned long total_tail = 0;
	struct cpu_key end_key;	
	struct item_head ind_ih;	
	int blk_size, retval;	
	unp_t unfm_ptr;		

	BUG_ON(!th->t_trans_id);

	REISERFS_SB(sb)->s_direct2indirect++;

	blk_size = sb->s_blocksize;

	copy_item_head(&ind_ih, p_le_ih);
	set_le_ih_k_offset(&ind_ih, tail_offset);
	set_le_ih_k_type(&ind_ih, TYPE_INDIRECT);

	
	make_cpu_key(&end_key, inode, tail_offset, TYPE_INDIRECT, 4);

	
	if (search_for_position_by_key(sb, &end_key, path) == POSITION_FOUND) {
		reiserfs_error(sb, "PAP-14030",
			       "pasted or inserted byte exists in "
			       "the tree %K. Use fsck to repair.", &end_key);
		pathrelse(path);
		return -EIO;
	}

	p_le_ih = PATH_PITEM_HEAD(path);

	unfm_ptr = cpu_to_le32(unbh->b_blocknr);

	if (is_statdata_le_ih(p_le_ih)) {
		
		set_ih_free_space(&ind_ih, 0);	
		put_ih_item_len(&ind_ih, UNFM_P_SIZE);
		PATH_LAST_POSITION(path)++;
		retval =
		    reiserfs_insert_item(th, path, &end_key, &ind_ih, inode,
					 (char *)&unfm_ptr);
	} else {
		
		retval = reiserfs_paste_into_item(th, path, &end_key, inode,
						    (char *)&unfm_ptr,
						    UNFM_P_SIZE);
	}
	if (retval) {
		return retval;
	}
	
	

	
	make_cpu_key(&end_key, inode, max_reiserfs_offset(inode), TYPE_DIRECT,
		     4);

	while (1) {
		int tail_size;

		if (search_for_position_by_key(sb, &end_key, path) ==
		    POSITION_FOUND)
			reiserfs_panic(sb, "PAP-14050",
				       "direct item (%K) not found", &end_key);
		p_le_ih = PATH_PITEM_HEAD(path);
		RFALSE(!is_direct_le_ih(p_le_ih),
		       "vs-14055: direct item expected(%K), found %h",
		       &end_key, p_le_ih);
		tail_size = (le_ih_k_offset(p_le_ih) & (blk_size - 1))
		    + ih_item_len(p_le_ih) - 1;

		if (!unbh->b_page || buffer_uptodate(unbh)
		    || PageUptodate(unbh->b_page)) {
			up_to_date_bh = NULL;
		} else {
			up_to_date_bh = unbh;
		}
		retval = reiserfs_delete_item(th, path, &end_key, inode,
						up_to_date_bh);

		total_tail += retval;
		if (tail_size == retval)
			
			break;

	}
	if (up_to_date_bh) {
		unsigned pgoff =
		    (tail_offset + total_tail - 1) & (PAGE_CACHE_SIZE - 1);
		char *kaddr = kmap_atomic(up_to_date_bh->b_page);
		memset(kaddr + pgoff, 0, blk_size - total_tail);
		kunmap_atomic(kaddr);
	}

	REISERFS_I(inode)->i_first_direct_byte = U32_MAX;

	return 0;
}
コード例 #14
0
/*
 * Prepare the write for the inline data.
 * If the the data can be written into the inode, we just read
 * the page and make it uptodate, and start the journal.
 * Otherwise read the page, makes it dirty so that it can be
 * handle in writepages(the i_disksize update is left to the
 * normal ext4_da_write_end).
 */
int ext4_da_write_inline_data_begin(struct address_space *mapping,
				    struct inode *inode,
				    loff_t pos, unsigned len,
				    unsigned flags,
				    struct page **pagep,
				    void **fsdata)
{
	int ret, inline_size;
	handle_t *handle;
	struct page *page;
	struct ext4_iloc iloc;

	ret = ext4_get_inode_loc(inode, &iloc);
	if (ret)
		return ret;

	handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
	if (IS_ERR(handle)) {
		ret = PTR_ERR(handle);
		handle = NULL;
		goto out;
	}

	inline_size = ext4_get_max_inline_size(inode);

	ret = -ENOSPC;
	if (inline_size >= pos + len) {
		ret = ext4_prepare_inline_data(handle, inode, pos + len);
		if (ret && ret != -ENOSPC)
			goto out;
	}

	if (ret == -ENOSPC) {
		ret = ext4_da_convert_inline_data_to_extent(mapping,
							    inode,
							    flags,
							    fsdata);
		goto out;
	}

	/*
	 * We cannot recurse into the filesystem as the transaction
	 * is already started.
	 */
	flags |= AOP_FLAG_NOFS;

	page = grab_cache_page_write_begin(mapping, 0, flags);
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}

	down_read(&EXT4_I(inode)->xattr_sem);
	if (!ext4_has_inline_data(inode)) {
		ret = 0;
		goto out_release_page;
	}

	if (!PageUptodate(page)) {
		ret = ext4_read_inline_page(inode, page);
		if (ret < 0)
			goto out_release_page;
	}

	up_read(&EXT4_I(inode)->xattr_sem);
	*pagep = page;
	handle = NULL;
	brelse(iloc.bh);
	return 1;
out_release_page:
	up_read(&EXT4_I(inode)->xattr_sem);
	unlock_page(page);
	page_cache_release(page);
out:
	if (handle)
		ext4_journal_stop(handle);
	brelse(iloc.bh);
	return ret;
}
コード例 #15
0
ファイル: inode.c プロジェクト: acassis/emlinux-ssd1935
/*
 * Returns a pointer to a buffer containing at least LEN bytes of
 * filesystem starting at byte offset OFFSET into the filesystem.
 */
static void *cramfs_read_comm(struct super_block *sb, unsigned int offset, unsigned int len)
{
	struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
	struct page *pages[BLKS_PER_BUF];
	unsigned i, blocknr, buffer;
	unsigned long devsize;
	char *data;

	if (!len)
		return NULL;
	blocknr = offset >> PAGE_CACHE_SHIFT;
	offset &= PAGE_CACHE_SIZE - 1;

	/* Check if an existing buffer already has the data.. */
	for (i = 0; i < READ_BUFFERS; i++) {
		unsigned int blk_offset;

		if (buffer_dev[i] != sb)
			continue;
		if (blocknr < buffer_blocknr[i])
			continue;
		blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_CACHE_SHIFT;
		blk_offset += offset;
		if (blk_offset + len > BUFFER_SIZE)
			continue;
		return read_buffers[i] + blk_offset;
	}

	devsize = mapping->host->i_size >> PAGE_CACHE_SHIFT;

	/* Ok, read in BLKS_PER_BUF pages completely first. */
	for (i = 0; i < BLKS_PER_BUF; i++) {
		struct page *page = NULL;

		if (blocknr + i < devsize) {
			page = read_mapping_page_async(mapping, blocknr + i,
									NULL);
			/* synchronous error? */
			if (IS_ERR(page))
				page = NULL;
		}
		pages[i] = page;
	}

	for (i = 0; i < BLKS_PER_BUF; i++) {
		struct page *page = pages[i];
		if (page) {
			wait_on_page_locked(page);
			if (!PageUptodate(page)) {
				/* asynchronous error */
				page_cache_release(page);
				pages[i] = NULL;
			}
		}
	}

	buffer = next_buffer;
	next_buffer = NEXT_BUFFER(buffer);
	buffer_blocknr[buffer] = blocknr;
	buffer_dev[buffer] = sb;

	data = read_buffers[buffer];
	for (i = 0; i < BLKS_PER_BUF; i++) {
		struct page *page = pages[i];
		if (page) {
			memcpy(data, kmap(page), PAGE_CACHE_SIZE);
			kunmap(page);
			page_cache_release(page);
		} else
			memset(data, 0, PAGE_CACHE_SIZE);
		data += PAGE_CACHE_SIZE;
	}
	return read_buffers[buffer] + offset;
}
コード例 #16
0
ファイル: ops_address.c プロジェクト: Mr-Aloof/wl500g
static int gfs2_write_begin(struct file *file, struct address_space *mapping,
			    loff_t pos, unsigned len, unsigned flags,
			    struct page **pagep, void **fsdata)
{
	struct gfs2_inode *ip = GFS2_I(mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
	unsigned int data_blocks, ind_blocks, rblocks;
	int alloc_required;
	int error = 0;
	struct gfs2_alloc *al;
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	unsigned from = pos & (PAGE_CACHE_SIZE - 1);
	unsigned to = from + len;
	struct page *page;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &ip->i_gh);
	error = gfs2_glock_nq_atime(&ip->i_gh);
	if (unlikely(error))
		goto out_uninit;

	error = -ENOMEM;
	page = grab_cache_page_write_begin(mapping, index, flags);
	*pagep = page;
	if (!page)
		goto out_unlock;

	gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);

	error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
	if (error)
		goto out_putpage;


	ip->i_alloc.al_requested = 0;
	if (alloc_required) {
		al = gfs2_alloc_get(ip);

		error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
		if (error)
			goto out_alloc_put;

		error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
		if (error)
			goto out_qunlock;

		al->al_requested = data_blocks + ind_blocks;
		error = gfs2_inplace_reserve(ip);
		if (error)
			goto out_qunlock;
	}

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;

	error = gfs2_trans_begin(sdp, rblocks, 0);
	if (error)
		goto out;

	if (gfs2_is_stuffed(ip)) {
		if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
			error = gfs2_unstuff_dinode(ip, page);
			if (error == 0)
				goto prepare_write;
		} else if (!PageUptodate(page))
			error = stuffed_readpage(ip, page);
		goto out;
	}

prepare_write:
	error = block_prepare_write(page, from, to, gfs2_get_block);

out:
	if (error) {
		gfs2_trans_end(sdp);
		if (alloc_required) {
			gfs2_inplace_release(ip);
out_qunlock:
			gfs2_quota_unlock(ip);
out_alloc_put:
			gfs2_alloc_put(ip);
		}
out_putpage:
		page_cache_release(page);
		if (pos + len > ip->i_inode.i_size)
			vmtruncate(&ip->i_inode, ip->i_inode.i_size);
out_unlock:
		gfs2_glock_dq_m(1, &ip->i_gh);
out_uninit:
		gfs2_holder_uninit(&ip->i_gh);
	}

	return error;
}
コード例 #17
0
ファイル: file_direct.c プロジェクト: 7799/linux
/* Read separately compressed datablock directly into page cache */
int squashfs_readpage_block(struct page *target_page, u64 block, int bsize)

{
	struct inode *inode = target_page->mapping->host;
	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;

	int file_end = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
	int mask = (1 << (msblk->block_log - PAGE_CACHE_SHIFT)) - 1;
	int start_index = target_page->index & ~mask;
	int end_index = start_index | mask;
	int i, n, pages, missing_pages, bytes, res = -ENOMEM;
	struct page **page;
	struct squashfs_page_actor *actor;
	void *pageaddr;

	if (end_index > file_end)
		end_index = file_end;

	pages = end_index - start_index + 1;

	page = kmalloc(sizeof(void *) * pages, GFP_KERNEL);
	if (page == NULL)
		return res;

	/*
	 * Create a "page actor" which will kmap and kunmap the
	 * page cache pages appropriately within the decompressor
	 */
	actor = squashfs_page_actor_init_special(page, pages, 0);
	if (actor == NULL)
		goto out;

	/* Try to grab all the pages covered by the Squashfs block */
	for (missing_pages = 0, i = 0, n = start_index; i < pages; i++, n++) {
		page[i] = (n == target_page->index) ? target_page :
			grab_cache_page_nowait(target_page->mapping, n);

		if (page[i] == NULL) {
			missing_pages++;
			continue;
		}

		if (PageUptodate(page[i])) {
			unlock_page(page[i]);
			page_cache_release(page[i]);
			page[i] = NULL;
			missing_pages++;
		}
	}

	if (missing_pages) {
		/*
		 * Couldn't get one or more pages, this page has either
		 * been VM reclaimed, but others are still in the page cache
		 * and uptodate, or we're racing with another thread in
		 * squashfs_readpage also trying to grab them.  Fall back to
		 * using an intermediate buffer.
		 */
		res = squashfs_read_cache(target_page, block, bsize, pages,
								page);
		if (res < 0)
			goto mark_errored;

		goto out;
	}

	/* Decompress directly into the page cache buffers */
	res = squashfs_read_data(inode->i_sb, block, bsize, NULL, actor);
	if (res < 0)
		goto mark_errored;

	/* Last page may have trailing bytes not filled */
	bytes = res % PAGE_CACHE_SIZE;
	if (bytes) {
		pageaddr = kmap_atomic(page[pages - 1]);
		memset(pageaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
		kunmap_atomic(pageaddr);
	}

	/* Mark pages as uptodate, unlock and release */
	for (i = 0; i < pages; i++) {
		flush_dcache_page(page[i]);
		SetPageUptodate(page[i]);
		unlock_page(page[i]);
		if (page[i] != target_page)
			page_cache_release(page[i]);
	}

	kfree(actor);
	kfree(page);

	return 0;

mark_errored:
	/* Decompression failed, mark pages as errored.  Target_page is
	 * dealt with by the caller
	 */
	for (i = 0; i < pages; i++) {
		if (page[i] == NULL || page[i] == target_page)
			continue;
		flush_dcache_page(page[i]);
		SetPageError(page[i]);
		unlock_page(page[i]);
		page_cache_release(page[i]);
	}

out:
	kfree(actor);
	kfree(page);
	return res;
}
コード例 #18
0
/* for every page of file: read page, cut part of extent pointing to this page,
   put data of page tree by tail item */
int extent2tail(struct file * file, struct unix_file_info *uf_info)
{
	int result;
	struct inode *inode;
	struct page *page;
	unsigned long num_pages, i;
	unsigned long start_page;
	reiser4_key from;
	reiser4_key to;
	unsigned count;
	__u64 offset;

	assert("nikita-3362", ea_obtained(uf_info));
	inode = unix_file_info_to_inode(uf_info);
	assert("nikita-3412", !IS_RDONLY(inode));
	assert("vs-1649", uf_info->container != UF_CONTAINER_TAILS);
	assert("", !reiser4_inode_get_flag(inode, REISER4_PART_IN_CONV));

	offset = 0;
	if (reiser4_inode_get_flag(inode, REISER4_PART_MIXED)) {
		/*
		 * file is marked on disk as there was a conversion which did
		 * not complete due to either crash or some error. Find which
		 * offset tail conversion stopped at
		 */
		result = find_start(inode, EXTENT_POINTER_ID, &offset);
		if (result == -ENOENT) {
			/* no extent found, everything is converted */
			uf_info->container = UF_CONTAINER_TAILS;
			complete_conversion(inode);
			return 0;
		} else if (result != 0)
			/* some other error */
			return result;
	}

	reiser4_inode_set_flag(inode, REISER4_PART_IN_CONV);

	/* number of pages in the file */
	num_pages =
	    (inode->i_size + - offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
	start_page = offset >> PAGE_CACHE_SHIFT;

	inode_file_plugin(inode)->key_by_inode(inode, offset, &from);
	to = from;

	result = 0;
	for (i = 0; i < num_pages; i++) {
		__u64 start_byte;

		result = reserve_extent2tail_iteration(inode);
		if (result != 0)
			break;
		if (i == 0 && offset == 0) {
			reiser4_inode_set_flag(inode, REISER4_PART_MIXED);
			reiser4_update_sd(inode);
		}

		page = read_mapping_page(inode->i_mapping,
					 (unsigned)(i + start_page), NULL);
		if (IS_ERR(page)) {
			result = PTR_ERR(page);
			break;
		}

		wait_on_page_locked(page);

		if (!PageUptodate(page)) {
			page_cache_release(page);
			result = RETERR(-EIO);
			break;
		}

		/* cut part of file we have read */
		start_byte = (__u64) ((i + start_page) << PAGE_CACHE_SHIFT);
		set_key_offset(&from, start_byte);
		set_key_offset(&to, start_byte + PAGE_CACHE_SIZE - 1);
		/*
		 * reiser4_cut_tree_object() returns -E_REPEAT to allow atom
		 * commits during over-long truncates. But
		 * extent->tail conversion should be performed in one
		 * transaction.
		 */
		result = reiser4_cut_tree(reiser4_tree_by_inode(inode), &from,
					  &to, inode, 0);

		if (result) {
			page_cache_release(page);
			break;
		}

		/* put page data into tree via tail_write */
		count = PAGE_CACHE_SIZE;
		if ((i == (num_pages - 1)) &&
		    (inode->i_size & ~PAGE_CACHE_MASK))
			/* last page can be incompleted */
			count = (inode->i_size & ~PAGE_CACHE_MASK);
		while (count) {
			loff_t pos = start_byte;

			assert("edward-1537",
			       file != NULL && file->f_dentry != NULL);
			assert("edward-1538",
			       file->f_dentry->d_inode == inode);

			result = reiser4_write_tail(file, inode,
						    (char __user *)kmap(page),
						    count, &pos);
			reiser4_free_file_fsdata(file);
			if (result <= 0) {
				warning("", "reiser4_write_tail failed");
				page_cache_release(page);
				reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV);
				return result;
			}
			count -= result;
		}

		/* release page */
		lock_page(page);
		/* page is already detached from jnode and mapping. */
		assert("vs-1086", page->mapping == NULL);
		assert("nikita-2690",
		       (!PagePrivate(page) && jprivate(page) == 0));
		/* waiting for writeback completion with page lock held is
		 * perfectly valid. */
		wait_on_page_writeback(page);
		reiser4_drop_page(page);
		/* release reference taken by read_cache_page() above */
		page_cache_release(page);

		drop_exclusive_access(uf_info);
		/*
		 * throttle the conversion.
		 * FIXME-EDWARD: Calculate and pass the precise number
		 * of pages that was dirtied
		 */
		reiser4_throttle_write(inode, 1);
		get_exclusive_access(uf_info);
		/*
		 * nobody is allowed to complete conversion but a process which
		 * started it
		 */
		assert("", reiser4_inode_get_flag(inode, REISER4_PART_MIXED));
	}

	reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV);

	if (i == num_pages) {
		/* file is converted to formatted items */
		assert("vs-1698", reiser4_inode_get_flag(inode,
							 REISER4_PART_MIXED));
		assert("vs-1260",
		       inode_has_no_jnodes(reiser4_inode_data(inode)));

		uf_info->container = UF_CONTAINER_TAILS;
		complete_conversion(inode);
		return 0;
	}
	/*
	 * conversion is not complete. Inode was already marked as
	 * REISER4_PART_MIXED and stat-data were updated at the first
	 * iteration of the loop above.
	 */
	warning("nikita-2282",
		"Partial conversion of %llu: %lu of %lu: %i",
		(unsigned long long)get_inode_oid(inode), i,
		num_pages, result);

	/* this flag should be cleared, otherwise get_exclusive_access_careful()
	   will fall into infinite loop */
	assert("edward-1550", !reiser4_inode_get_flag(inode,
						      REISER4_PART_IN_CONV));
	return result;
}
コード例 #19
0
ファイル: mpage.c プロジェクト: kgdhost/kernel-lge-e400-stock
/*
 * This is the worker routine which does all the work of mapping the disk
 * blocks and constructs largest possible bios, submits them for IO if the
 * blocks are not contiguous on the disk.
 *
 * We pass a buffer_head back and forth and use its buffer_mapped() flag to
 * represent the validity of its disk mapping and to decide when to do the next
 * get_block() call.
 */
static struct bio *
do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
		sector_t *last_block_in_bio, struct buffer_head *map_bh,
		unsigned long *first_logical_block, get_block_t get_block)
{
	struct inode *inode = page->mapping->host;
	const unsigned blkbits = inode->i_blkbits;
	const unsigned blocks_per_page = PAGE_CACHE_SIZE >> blkbits;
	const unsigned blocksize = 1 << blkbits;
	sector_t block_in_file;
	sector_t last_block;
	sector_t last_block_in_file;
	sector_t blocks[MAX_BUF_PER_PAGE];
	unsigned page_block;
	unsigned first_hole = blocks_per_page;
	struct block_device *bdev = NULL;
	int length;
	int fully_mapped = 1;
	unsigned nblocks;
	unsigned relative_block;

	if (page_has_buffers(page))
		goto confused;

	block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
	last_block = block_in_file + nr_pages * blocks_per_page;
	last_block_in_file = (i_size_read(inode) + blocksize - 1) >> blkbits;
	if (last_block > last_block_in_file)
		last_block = last_block_in_file;
	page_block = 0;

	/*
	 * Map blocks using the result from the previous get_blocks call first.
	 */
	nblocks = map_bh->b_size >> blkbits;
	if (buffer_mapped(map_bh) && block_in_file > *first_logical_block &&
			block_in_file < (*first_logical_block + nblocks)) {
		unsigned map_offset = block_in_file - *first_logical_block;
		unsigned last = nblocks - map_offset;

		for (relative_block = 0; ; relative_block++) {
			if (relative_block == last) {
				clear_buffer_mapped(map_bh);
				break;
			}
			if (page_block == blocks_per_page)
				break;
			blocks[page_block] = map_bh->b_blocknr + map_offset +
						relative_block;
			page_block++;
			block_in_file++;
		}
		bdev = map_bh->b_bdev;
	}

	/*
	 * Then do more get_blocks calls until we are done with this page.
	 */
	map_bh->b_page = page;
	while (page_block < blocks_per_page) {
		map_bh->b_state = 0;
		map_bh->b_size = 0;

		if (block_in_file < last_block) {
			map_bh->b_size = (last_block-block_in_file) << blkbits;
			if (get_block(inode, block_in_file, map_bh, 0))
				goto confused;
			*first_logical_block = block_in_file;
		}

		if (!buffer_mapped(map_bh)) {
			fully_mapped = 0;
			if (first_hole == blocks_per_page)
				first_hole = page_block;
			page_block++;
			block_in_file++;
			continue;
		}

		/* some filesystems will copy data into the page during
		 * the get_block call, in which case we don't want to
		 * read it again.  map_buffer_to_page copies the data
		 * we just collected from get_block into the page's buffers
		 * so readpage doesn't have to repeat the get_block call
		 */
		if (buffer_uptodate(map_bh)) {
			map_buffer_to_page(page, map_bh, page_block);
			goto confused;
		}
	
		if (first_hole != blocks_per_page)
			goto confused;		/* hole -> non-hole */

		/* Contiguous blocks? */
		if (page_block && blocks[page_block-1] != map_bh->b_blocknr-1)
			goto confused;
		nblocks = map_bh->b_size >> blkbits;
		for (relative_block = 0; ; relative_block++) {
			if (relative_block == nblocks) {
				clear_buffer_mapped(map_bh);
				break;
			} else if (page_block == blocks_per_page)
				break;
			blocks[page_block] = map_bh->b_blocknr+relative_block;
			page_block++;
			block_in_file++;
		}
		bdev = map_bh->b_bdev;
	}

	if (first_hole != blocks_per_page) {
		zero_user_segment(page, first_hole << blkbits, PAGE_CACHE_SIZE);
		if (first_hole == 0) {
			SetPageUptodate(page);
			unlock_page(page);
			goto out;
		}
	} else if (fully_mapped) {
		SetPageMappedToDisk(page);
	}

	if (fully_mapped && blocks_per_page == 1 && !PageUptodate(page) &&
                cleancache_get_page(page) == 0) {
                        SetPageUptodate(page);
                        goto confused;
                }

	/*
	 * This page will go to BIO.  Do we need to send this BIO off first?
	 */
	if (bio && (*last_block_in_bio != blocks[0] - 1))
		bio = mpage_bio_submit(READ, bio);

alloc_new:
	if (bio == NULL) {
		bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9),
			  	min_t(int, nr_pages, bio_get_nr_vecs(bdev)),
				GFP_KERNEL);
		if (bio == NULL)
			goto confused;
	}
コード例 #20
0
ファイル: file.c プロジェクト: 0xroot/Blackphone-BP1-Kernel
static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	unsigned long last_index;
	u64 pos = page->index << PAGE_CACHE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	struct gfs2_holder gh;
	struct gfs2_qadata *qa;
	loff_t size;
	int ret;

	/* Wait if fs is frozen. This is racy so we check again later on
	 * and retry if the fs has been frozen after the page lock has
	 * been acquired
	 */
	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out;

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) {
		lock_page(page);
		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
			ret = -EAGAIN;
			unlock_page(page);
		}
		goto out_unlock;
	}

	ret = -ENOMEM;
	qa = gfs2_qadata_get(ip);
	if (qa == NULL)
		goto out_unlock;

	ret = gfs2_quota_lock_check(ip);
	if (ret)
		goto out_alloc_put;
	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
	ret = gfs2_inplace_reserve(ip, data_blocks + ind_blocks);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks) {
		rblocks += RES_STATFS + RES_QUOTA;
		rblocks += gfs2_rg_blocks(ip);
	}
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	size = i_size_read(inode);
	last_index = (size - 1) >> PAGE_CACHE_SHIFT;
	/* Check page index against inode size */
	if (size == 0 || (page->index > last_index))
		goto out_trans_end;

	ret = -EAGAIN;
	/* If truncated, we must retry the operation, we may have raced
	 * with the glock demotion code.
	 */
	if (!PageUptodate(page) || page->mapping != inode->i_mapping)
		goto out_trans_end;

	/* Unstuff, if required, and allocate backing blocks for page */
	ret = 0;
	if (gfs2_is_stuffed(ip))
		ret = gfs2_unstuff_dinode(ip, page);
	if (ret == 0)
		ret = gfs2_allocate_page_backing(page);

out_trans_end:
	if (ret)
		unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_alloc_put:
	gfs2_qadata_put(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out:
	gfs2_holder_uninit(&gh);
	if (ret == 0) {
		set_page_dirty(page);
		/* This check must be post dropping of transaction lock */
		if (inode->i_sb->s_frozen == SB_UNFROZEN) {
			wait_on_page_writeback(page);
		} else {
			ret = -EAGAIN;
			unlock_page(page);
		}
	}
	return block_page_mkwrite_return(ret);
}
コード例 #21
0
ファイル: file.c プロジェクト: CSCLOG/beaglebone
static int jffs2_write_end(struct file *filp, struct address_space *mapping,
                           loff_t pos, unsigned len, unsigned copied,
                           struct page *pg, void *fsdata)
{
    /* Actually commit the write from the page cache page we're looking at.
     * For now, we write the full page out each time. It sucks, but it's simple
     */
    struct inode *inode = mapping->host;
    struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
    struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
    struct jffs2_raw_inode *ri;
    unsigned start = pos & (PAGE_CACHE_SIZE - 1);
    unsigned end = start + copied;
    unsigned aligned_start = start & ~3;
    int ret = 0;
    uint32_t writtenlen = 0;

    D1(printk(KERN_DEBUG "jffs2_write_end(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
              inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));

    /* We need to avoid deadlock with page_cache_read() in
       jffs2_garbage_collect_pass(). So the page must be
       up to date to prevent page_cache_read() from trying
       to re-lock it. */
    BUG_ON(!PageUptodate(pg));

    if (end == PAGE_CACHE_SIZE) {
        /* When writing out the end of a page, write out the
           _whole_ page. This helps to reduce the number of
           nodes in files which have many short writes, like
           syslog files. */
        aligned_start = 0;
    }

    ri = jffs2_alloc_raw_inode();

    if (!ri) {
        D1(printk(KERN_DEBUG "jffs2_write_end(): Allocation of raw inode failed\n"));
        unlock_page(pg);
        page_cache_release(pg);
        return -ENOMEM;
    }

    /* Set the fields that the generic jffs2_write_inode_range() code can't find */
    ri->ino = cpu_to_je32(inode->i_ino);
    ri->mode = cpu_to_jemode(inode->i_mode);
    ri->uid = cpu_to_je16(inode->i_uid);
    ri->gid = cpu_to_je16(inode->i_gid);
    ri->isize = cpu_to_je32((uint32_t)inode->i_size);
    ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());

    /* In 2.4, it was already kmapped by generic_file_write(). Doesn't
       hurt to do it again. The alternative is ifdefs, which are ugly. */
    kmap(pg);

    ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
                                  (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
                                  end - aligned_start, &writtenlen);

    kunmap(pg);

    if (ret) {
        /* There was an error writing. */
        SetPageError(pg);
    }

    /* Adjust writtenlen for the padding we did, so we don't confuse our caller */
    writtenlen -= min(writtenlen, (start - aligned_start));

    if (writtenlen) {
        if (inode->i_size < pos + writtenlen) {
            inode->i_size = pos + writtenlen;
            inode->i_blocks = (inode->i_size + 511) >> 9;

            inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
        }
    }
コード例 #22
0
static int wrapfs_writepage(struct page *page, struct writeback_control *wbc)
{
        int err = -EIO;
        struct inode *inode;
        struct inode *lower_inode;
        struct page *lower_page;
        struct address_space *lower_mapping; /* lower inode mapping */
        gfp_t mask;

        /*printk(KERN_ALERT "in writepage() \n");*/

        BUG_ON(!PageUptodate(page));
        inode = page->mapping->host;
        /* if no lower inode, nothing to do */
        if (!inode || !WRAPFS_I(inode) || WRAPFS_I(inode)->lower_inode) {
                err = 0;
                goto out;
        }
        lower_inode = wrapfs_lower_inode(inode);
        lower_mapping = lower_inode->i_mapping;

        /*
         * find lower page (returns a locked page)
         *
         * We turn off __GFP_FS while we look for or create a new lower
         * page.  This prevents a recursion into the file system code, which
         * under memory pressure conditions could lead to a deadlock.  This
         * is similar to how the loop driver behaves (see loop_set_fd in
         * drivers/block/loop.c).  If we can't find the lower page, we
         * redirty our page and return "success" so that the VM will call us
         * again in the (hopefully near) future.
         */
        mask = mapping_gfp_mask(lower_mapping) & ~(__GFP_FS);
        lower_page = find_or_create_page(lower_mapping, page->index, mask);
        if (!lower_page) {
                err = 0;
                set_page_dirty(page);
                goto out;
        }

        /* copy page data from our upper page to the lower page */
        copy_highpage(lower_page, page);
        flush_dcache_page(lower_page);
        SetPageUptodate(lower_page);
        set_page_dirty(lower_page);

        /*
         * Call lower writepage (expects locked page).  However, if we are
         * called with wbc->for_reclaim, then the VFS/VM just wants to
         * reclaim our page.  Therefore, we don't need to call the lower
         * ->writepage: just copy our data to the lower page (already done
         * above), then mark the lower page dirty and unlock it, and return
         * success.
         */
        if (wbc->for_reclaim) {
                unlock_page(lower_page);
                goto out_release;
        }

        BUG_ON(!lower_mapping->a_ops->writepage);
        wait_on_page_writeback(lower_page); /* prevent multiple writers */
        clear_page_dirty_for_io(lower_page); /* emulate VFS behavior */
        err = lower_mapping->a_ops->writepage(lower_page, wbc);
        if (err < 0)
                goto out_release;

        /*
         * Lower file systems such as ramfs and tmpfs, may return
         * AOP_WRITEPAGE_ACTIVATE so that the VM won't try to (pointlessly)
         * write the page again for a while.  But those lower file systems
         * also set the page dirty bit back again.  Since we successfully
         * copied our page data to the lower page, then the VM will come
         * back to the lower page (directly) and try to flush it.  So we can
         * save the VM the hassle of coming back to our page and trying to
         * flush too.  Therefore, we don't re-dirty our own page, and we
         * never return AOP_WRITEPAGE_ACTIVATE back to the VM (we consider
         * this a success).
         *
         * We also unlock the lower page if the lower ->writepage returned
         * AOP_WRITEPAGE_ACTIVATE.  (This "anomalous" behaviour may be
         * addressed in future shmem/VM code.)
         */
        if (err == AOP_WRITEPAGE_ACTIVATE) {
                err = 0;
                unlock_page(lower_page);
        }

        /* all is well */

        /* lower mtimes have changed: update ours */
        /*	fsstack_copy_inode_size(dentry->d_inode,
				lower_file->f_path.dentry->d_inode);
        fsstack_copy_attr_times(dentry->d_inode,
				lower_file->f_path.dentry->d_inode);	
        */

out_release:
        /* b/c find_or_create_page increased refcnt */
        page_cache_release(lower_page);
out:
        /*
         * We unlock our page unconditionally, because we never return
         * AOP_WRITEPAGE_ACTIVATE.
         */
        unlock_page(page);
        return err;
}
コード例 #23
0
ファイル: page-writeback.c プロジェクト: Addision/LVS
/**
 * write_one_page - write out a single page and optionally wait on I/O
 * @page: the page to write
 * @wait: if true, wait on writeout
 *
 * The page must be locked by the caller and will be unlocked upon return.
 *
 * write_one_page() returns a negative error code if I/O failed.
 */
int write_one_page(struct page *page, int wait)
{
	struct address_space *mapping = page->mapping;
	int ret = 0;
	struct writeback_control wbc = {
		.sync_mode = WB_SYNC_ALL,
		.nr_to_write = 1,
	};

	BUG_ON(!PageLocked(page));

	if (wait)
		wait_on_page_writeback(page);

	if (clear_page_dirty_for_io(page)) {
		page_cache_get(page);
		ret = mapping->a_ops->writepage(page, &wbc);
		if (ret == 0 && wait) {
			wait_on_page_writeback(page);
			if (PageError(page))
				ret = -EIO;
		}
		page_cache_release(page);
	} else {
		unlock_page(page);
	}
	return ret;
}
EXPORT_SYMBOL(write_one_page);

/*
 * For address_spaces which do not use buffers nor write back.
 */
int __set_page_dirty_no_writeback(struct page *page)
{
	if (!PageDirty(page))
		SetPageDirty(page);
	return 0;
}

/*
 * Helper function for set_page_dirty family.
 * NOTE: This relies on being atomic wrt interrupts.
 */
void account_page_dirtied(struct page *page, struct address_space *mapping)
{
	if (mapping_cap_account_dirty(mapping)) {
		__inc_zone_page_state(page, NR_FILE_DIRTY);
		__inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
		task_dirty_inc(current);
		task_io_account_write(PAGE_CACHE_SIZE);
	}
}

/*
 * For address_spaces which do not use buffers.  Just tag the page as dirty in
 * its radix tree.
 *
 * This is also used when a single buffer is being dirtied: we want to set the
 * page dirty in that case, but not all the buffers.  This is a "bottom-up"
 * dirtying, whereas __set_page_dirty_buffers() is a "top-down" dirtying.
 *
 * Most callers have locked the page, which pins the address_space in memory.
 * But zap_pte_range() does not lock the page, however in that case the
 * mapping is pinned by the vma's ->vm_file reference.
 *
 * We take care to handle the case where the page was truncated from the
 * mapping by re-checking page_mapping() inside tree_lock.
 */
int __set_page_dirty_nobuffers(struct page *page)
{
	if (!TestSetPageDirty(page)) {
		struct address_space *mapping = page_mapping(page);
		struct address_space *mapping2;

		if (!mapping)
			return 1;

		spin_lock_irq(&mapping->tree_lock);
		mapping2 = page_mapping(page);
		if (mapping2) { /* Race with truncate? */
			BUG_ON(mapping2 != mapping);
			WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
			account_page_dirtied(page, mapping);
			radix_tree_tag_set(&mapping->page_tree,
				page_index(page), PAGECACHE_TAG_DIRTY);
		}
		spin_unlock_irq(&mapping->tree_lock);
		if (mapping->host) {
			/* !PageAnon && !swapper_space */
			__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
		}
		return 1;
	}
	return 0;
}
EXPORT_SYMBOL(__set_page_dirty_nobuffers);

/*
 * When a writepage implementation decides that it doesn't want to write this
 * page for some reason, it should redirty the locked page via
 * redirty_page_for_writepage() and it should then unlock the page and return 0
 */
int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
{
	wbc->pages_skipped++;
	return __set_page_dirty_nobuffers(page);
}
コード例 #24
0
ファイル: write.c プロジェクト: friackazoid/linux-2.6
/*
 * If the page cache is marked as unsafe or invalid, then we can't rely on
 * the PageUptodate() flag. In this case, we will need to turn off
 * write optimisations that depend on the page contents being correct.
 */
static int nfs_write_pageuptodate(struct page *page, struct inode *inode)
{
	return PageUptodate(page) &&
		!(NFS_I(inode)->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA));
}
コード例 #25
0
ファイル: file.c プロジェクト: 7799/linux
static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = file_inode(vma->vm_file);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned long last_index;
	u64 pos = page->index << PAGE_CACHE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	struct gfs2_holder gh;
	loff_t size;
	int ret;

	sb_start_pagefault(inode->i_sb);

	/* Update file times before taking page lock */
	file_update_time(vma->vm_file);

	ret = get_write_access(inode);
	if (ret)
		goto out;

	ret = gfs2_rs_alloc(ip);
	if (ret)
		goto out_write_access;

	gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out_uninit;

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) {
		lock_page(page);
		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
			ret = -EAGAIN;
			unlock_page(page);
		}
		goto out_unlock;
	}

	ret = gfs2_rindex_update(sdp);
	if (ret)
		goto out_unlock;

	ret = gfs2_quota_lock_check(ip);
	if (ret)
		goto out_unlock;
	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
	ap.target = data_blocks + ind_blocks;
	ret = gfs2_inplace_reserve(ip, &ap);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks) {
		rblocks += RES_STATFS + RES_QUOTA;
		rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
	}
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	size = i_size_read(inode);
	last_index = (size - 1) >> PAGE_CACHE_SHIFT;
	/* Check page index against inode size */
	if (size == 0 || (page->index > last_index))
		goto out_trans_end;

	ret = -EAGAIN;
	/* If truncated, we must retry the operation, we may have raced
	 * with the glock demotion code.
	 */
	if (!PageUptodate(page) || page->mapping != inode->i_mapping)
		goto out_trans_end;

	/* Unstuff, if required, and allocate backing blocks for page */
	ret = 0;
	if (gfs2_is_stuffed(ip))
		ret = gfs2_unstuff_dinode(ip, page);
	if (ret == 0)
		ret = gfs2_allocate_page_backing(page);

out_trans_end:
	if (ret)
		unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	if (ret == 0) {
		set_page_dirty(page);
		wait_for_stable_page(page);
	}
out_write_access:
	put_write_access(inode);
out:
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}

static const struct vm_operations_struct gfs2_vm_ops = {
	.fault = filemap_fault,
	.map_pages = filemap_map_pages,
	.page_mkwrite = gfs2_page_mkwrite,
	.remap_pages = generic_file_remap_pages,
};

/**
 * gfs2_mmap -
 * @file: The file to map
 * @vma: The VMA which described the mapping
 *
 * There is no need to get a lock here unless we should be updating
 * atime. We ignore any locking errors since the only consequence is
 * a missed atime update (which will just be deferred until later).
 *
 * Returns: 0
 */

static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);

	if (!(file->f_flags & O_NOATIME) &&
	    !IS_NOATIME(&ip->i_inode)) {
		struct gfs2_holder i_gh;
		int error;

		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		/* grab lock to update inode */
		gfs2_glock_dq_uninit(&i_gh);
		file_accessed(file);
	}
	vma->vm_ops = &gfs2_vm_ops;

	return 0;
}

/**
 * gfs2_open_common - This is common to open and atomic_open
 * @inode: The inode being opened
 * @file: The file being opened
 *
 * This maybe called under a glock or not depending upon how it has
 * been called. We must always be called under a glock for regular
 * files, however. For other file types, it does not matter whether
 * we hold the glock or not.
 *
 * Returns: Error code or 0 for success
 */

int gfs2_open_common(struct inode *inode, struct file *file)
{
	struct gfs2_file *fp;
	int ret;

	if (S_ISREG(inode->i_mode)) {
		ret = generic_file_open(inode, file);
		if (ret)
			return ret;
	}

	fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
	if (!fp)
		return -ENOMEM;

	mutex_init(&fp->f_fl_mutex);

	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
	file->private_data = fp;
	return 0;
}

/**
 * gfs2_open - open a file
 * @inode: the inode to open
 * @file: the struct file for this opening
 *
 * After atomic_open, this function is only used for opening files
 * which are already cached. We must still get the glock for regular
 * files to ensure that we have the file size uptodate for the large
 * file check which is in the common code. That is only an issue for
 * regular files though.
 *
 * Returns: errno
 */

static int gfs2_open(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder i_gh;
	int error;
	bool need_unlock = false;

	if (S_ISREG(ip->i_inode.i_mode)) {
		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		need_unlock = true;
	}

	error = gfs2_open_common(inode, file);

	if (need_unlock)
		gfs2_glock_dq_uninit(&i_gh);

	return error;
}

/**
 * gfs2_release - called to close a struct file
 * @inode: the inode the struct file belongs to
 * @file: the struct file being closed
 *
 * Returns: errno
 */

static int gfs2_release(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);

	kfree(file->private_data);
	file->private_data = NULL;

	if (!(file->f_mode & FMODE_WRITE))
		return 0;

	gfs2_rs_delete(ip, &inode->i_writecount);
	return 0;
}

/**
 * gfs2_fsync - sync the dirty data for a file (across the cluster)
 * @file: the file that points to the dentry
 * @start: the start position in the file to sync
 * @end: the end position in the file to sync
 * @datasync: set if we can ignore timestamp changes
 *
 * We split the data flushing here so that we don't wait for the data
 * until after we've also sent the metadata to disk. Note that for
 * data=ordered, we will write & wait for the data at the log flush
 * stage anyway, so this is unlikely to make much of a difference
 * except in the data=writeback case.
 *
 * If the fdatawrite fails due to any reason except -EIO, we will
 * continue the remainder of the fsync, although we'll still report
 * the error at the end. This is to match filemap_write_and_wait_range()
 * behaviour.
 *
 * Returns: errno
 */

static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
		      int datasync)
{
	struct address_space *mapping = file->f_mapping;
	struct inode *inode = mapping->host;
	int sync_state = inode->i_state & I_DIRTY;
	struct gfs2_inode *ip = GFS2_I(inode);
	int ret = 0, ret1 = 0;

	if (mapping->nrpages) {
		ret1 = filemap_fdatawrite_range(mapping, start, end);
		if (ret1 == -EIO)
			return ret1;
	}

	if (!gfs2_is_jdata(ip))
		sync_state &= ~I_DIRTY_PAGES;
	if (datasync)
		sync_state &= ~I_DIRTY_SYNC;

	if (sync_state) {
		ret = sync_inode_metadata(inode, 1);
		if (ret)
			return ret;
		if (gfs2_is_jdata(ip))
			filemap_write_and_wait(mapping);
		gfs2_ail_flush(ip->i_gl, 1);
	}

	if (mapping->nrpages)
		ret = filemap_fdatawait_range(mapping, start, end);

	return ret ? ret : ret1;
}

/**
 * gfs2_file_aio_write - Perform a write to a file
 * @iocb: The io context
 * @iov: The data to write
 * @nr_segs: Number of @iov segments
 * @pos: The file position
 *
 * We have to do a lock/unlock here to refresh the inode size for
 * O_APPEND writes, otherwise we can land up writing at the wrong
 * offset. There is still a race, but provided the app is using its
 * own file locking, this will make O_APPEND work as expected.
 *
 */

static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
				   unsigned long nr_segs, loff_t pos)
{
	struct file *file = iocb->ki_filp;
	size_t writesize = iov_length(iov, nr_segs);
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	int ret;

	ret = gfs2_rs_alloc(ip);
	if (ret)
		return ret;

	gfs2_size_hint(file, pos, writesize);

	if (file->f_flags & O_APPEND) {
		struct gfs2_holder gh;

		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
		if (ret)
			return ret;
		gfs2_glock_dq_uninit(&gh);
	}

	return generic_file_aio_write(iocb, iov, nr_segs, pos);
}

static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
			   int mode)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct buffer_head *dibh;
	int error;
	loff_t size = len;
	unsigned int nr_blks;
	sector_t lblock = offset >> inode->i_blkbits;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(error))
		return error;

	gfs2_trans_add_meta(ip->i_gl, dibh);

	if (gfs2_is_stuffed(ip)) {
		error = gfs2_unstuff_dinode(ip, NULL);
		if (unlikely(error))
			goto out;
	}

	while (len) {
		struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
		bh_map.b_size = len;
		set_buffer_zeronew(&bh_map);

		error = gfs2_block_map(inode, lblock, &bh_map, 1);
		if (unlikely(error))
			goto out;
		len -= bh_map.b_size;
		nr_blks = bh_map.b_size >> inode->i_blkbits;
		lblock += nr_blks;
		if (!buffer_new(&bh_map))
			continue;
		if (unlikely(!buffer_zeronew(&bh_map))) {
			error = -EIO;
			goto out;
		}
	}
	if (offset + size > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE))
		i_size_write(inode, offset + size);

	mark_inode_dirty(inode);

out:
	brelse(dibh);
	return error;
}

static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
			    unsigned int *data_blocks, unsigned int *ind_blocks)
{
	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	unsigned int max_blocks = ip->i_rgd->rd_free_clone;
	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);

	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
		max_data -= tmp;
	}
	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
	   so it might end up with fewer data blocks */
	if (max_data <= *data_blocks)
		return;
	*data_blocks = max_data;
	*ind_blocks = max_blocks - max_data;
	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
	if (*len > max) {
		*len = max;
		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
	}
}

static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
			   loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	loff_t bytes, max_bytes;
	int error;
	const loff_t pos = offset;
	const loff_t count = len;
	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
	loff_t max_chunk_size = UINT_MAX & bsize_mask;
	struct gfs2_holder gh;

	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;

	/* We only support the FALLOC_FL_KEEP_SIZE mode */
	if (mode & ~FALLOC_FL_KEEP_SIZE)
		return -EOPNOTSUPP;

	offset &= bsize_mask;

	len = next - offset;
	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
	if (!bytes)
		bytes = UINT_MAX;
	bytes &= bsize_mask;
	if (bytes == 0)
		bytes = sdp->sd_sb.sb_bsize;

	error = gfs2_rs_alloc(ip);
	if (error)
		return error;

	mutex_lock(&inode->i_mutex);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	error = gfs2_glock_nq(&gh);
	if (unlikely(error))
		goto out_uninit;

	gfs2_size_hint(file, offset, len);

	while (len > 0) {
		if (len < bytes)
			bytes = len;
		if (!gfs2_write_alloc_required(ip, offset, bytes)) {
			len -= bytes;
			offset += bytes;
			continue;
		}
		error = gfs2_quota_lock_check(ip);
		if (error)
			goto out_unlock;

retry:
		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);

		ap.target = data_blocks + ind_blocks;
		error = gfs2_inplace_reserve(ip, &ap);
		if (error) {
			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
				bytes >>= 1;
				bytes &= bsize_mask;
				if (bytes == 0)
					bytes = sdp->sd_sb.sb_bsize;
				goto retry;
			}
			goto out_qunlock;
		}
		max_bytes = bytes;
		calc_max_reserv(ip, (len > max_chunk_size)? max_chunk_size: len,
				&max_bytes, &data_blocks, &ind_blocks);

		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
			  RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
		if (gfs2_is_jdata(ip))
			rblocks += data_blocks ? data_blocks : 1;

		error = gfs2_trans_begin(sdp, rblocks,
					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
		if (error)
			goto out_trans_fail;

		error = fallocate_chunk(inode, offset, max_bytes, mode);
		gfs2_trans_end(sdp);

		if (error)
			goto out_trans_fail;

		len -= max_bytes;
		offset += max_bytes;
		gfs2_inplace_release(ip);
		gfs2_quota_unlock(ip);
	}

	if (error == 0)
		error = generic_write_sync(file, pos, count);
	goto out_unlock;

out_trans_fail:
	gfs2_inplace_release(ip);
out_qunlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	mutex_unlock(&inode->i_mutex);
	return error;
}

#ifdef CONFIG_GFS2_FS_LOCKING_DLM

/**
 * gfs2_setlease - acquire/release a file lease
 * @file: the file pointer
 * @arg: lease type
 * @fl: file lock
 *
 * We don't currently have a way to enforce a lease across the whole
 * cluster; until we do, disable leases (by just returning -EINVAL),
 * unless the administrator has requested purely local locking.
 *
 * Locking: called under i_lock
 *
 * Returns: errno
 */

static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
{
	return -EINVAL;
}

/**
 * gfs2_lock - acquire/release a posix lock on a file
 * @file: the file pointer
 * @cmd: either modify or retrieve lock state, possibly wait
 * @fl: type and range of lock
 *
 * Returns: errno
 */

static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;

	if (!(fl->fl_flags & FL_POSIX))
		return -ENOLCK;
	if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
		return -ENOLCK;

	if (cmd == F_CANCELLK) {
		/* Hack: */
		cmd = F_SETLK;
		fl->fl_type = F_UNLCK;
	}
	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
		if (fl->fl_type == F_UNLCK)
			posix_lock_file_wait(file, fl);
		return -EIO;
	}
	if (IS_GETLK(cmd))
		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
	else if (fl->fl_type == F_UNLCK)
		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
	else
		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
}

static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
	struct gfs2_file *fp = file->private_data;
	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	struct gfs2_glock *gl;
	unsigned int state;
	int flags;
	int error = 0;

	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;

	mutex_lock(&fp->f_fl_mutex);

	gl = fl_gh->gh_gl;
	if (gl) {
		if (fl_gh->gh_state == state)
			goto out;
		flock_lock_file_wait(file,
				     &(struct file_lock){.fl_type = F_UNLCK});
		gfs2_glock_dq_wait(fl_gh);
		gfs2_holder_reinit(state, flags, fl_gh);
	} else {
		error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
				       &gfs2_flock_glops, CREATE, &gl);
		if (error)
			goto out;
		gfs2_holder_init(gl, state, flags, fl_gh);
		gfs2_glock_put(gl);
	}
	error = gfs2_glock_nq(fl_gh);
	if (error) {
		gfs2_holder_uninit(fl_gh);
		if (error == GLR_TRYFAILED)
			error = -EAGAIN;
	} else {
		error = flock_lock_file_wait(file, fl);
		gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
	}

out:
	mutex_unlock(&fp->f_fl_mutex);
	return error;
}
コード例 #26
0
ファイル: inline.c プロジェクト: Fechinator/FechdaKernel
int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page)
{
	void *src_addr, *dst_addr;
	struct f2fs_io_info fio = {
		.type = DATA,
		.rw = WRITE_SYNC | REQ_PRIO,
	};
	int dirty, err;

	f2fs_bug_on(F2FS_I_SB(dn->inode), page->index);

	if (!f2fs_exist_data(dn->inode))
		goto clear_out;

	err = f2fs_reserve_block(dn, 0);
	if (err)
		return err;

	f2fs_wait_on_page_writeback(page, DATA);

	if (PageUptodate(page))
		goto no_update;

	zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);

	/* Copy the whole inline data block */
	src_addr = inline_data_addr(dn->inode_page);
	dst_addr = kmap_atomic(page);
	memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
	flush_dcache_page(page);
	kunmap_atomic(dst_addr);
	SetPageUptodate(page);
no_update:
	/* clear dirty state */
	dirty = clear_page_dirty_for_io(page);

	/* write data page to try to make data consistent */
	set_page_writeback(page);
	fio.blk_addr = dn->data_blkaddr;
	write_data_page(page, dn, &fio);
	update_extent_cache(dn);
	f2fs_wait_on_page_writeback(page, DATA);
	if (dirty)
		inode_dec_dirty_pages(dn->inode);

	/* this converted inline_data should be recovered. */
	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);

	/* clear inline data and flag after data writeback */
	truncate_inline_data(dn->inode_page);
clear_out:
	stat_dec_inline_inode(dn->inode);
	f2fs_clear_inline_inode(dn->inode);
	sync_inode_page(dn);
	f2fs_put_dnode(dn);
	return 0;
}

int f2fs_convert_inline_inode(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	struct dnode_of_data dn;
	struct page *ipage, *page;
	int err = 0;

	page = grab_cache_page(inode->i_mapping, 0);
	if (!page)
		return -ENOMEM;

	f2fs_lock_op(sbi);

	ipage = get_node_page(sbi, inode->i_ino);
	if (IS_ERR(ipage)) {
		err = PTR_ERR(ipage);
		goto out;
	}

	set_new_dnode(&dn, inode, ipage, ipage, 0);

	if (f2fs_has_inline_data(inode))
		err = f2fs_convert_inline_page(&dn, page);

	f2fs_put_dnode(&dn);
out:
	f2fs_unlock_op(sbi);

	f2fs_put_page(page, 1);
	return err;
}

int f2fs_write_inline_data(struct inode *inode, struct page *page)
{
	void *src_addr, *dst_addr;
	struct dnode_of_data dn;
	int err;

	set_new_dnode(&dn, inode, NULL, NULL, 0);
	err = get_dnode_of_data(&dn, 0, LOOKUP_NODE);
	if (err)
		return err;

	if (!f2fs_has_inline_data(inode)) {
		f2fs_put_dnode(&dn);
		return -EAGAIN;
	}

	f2fs_bug_on(F2FS_I_SB(inode), page->index);

	f2fs_wait_on_page_writeback(dn.inode_page, NODE);
	src_addr = kmap_atomic(page);
	dst_addr = inline_data_addr(dn.inode_page);
	memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
	kunmap_atomic(src_addr);

	set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
	set_inode_flag(F2FS_I(inode), FI_DATA_EXIST);

	sync_inode_page(&dn);
	f2fs_put_dnode(&dn);
	return 0;
}
コード例 #27
0
ファイル: ops_address.c プロジェクト: WiseMan787/ralink_sdk
static int gfs2_prepare_write(struct file *file, struct page *page,
			      unsigned from, unsigned to)
{
	struct gfs2_inode *ip = GFS2_I(page->mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
	unsigned int data_blocks, ind_blocks, rblocks;
	int alloc_required;
	int error = 0;
	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
	loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
	struct gfs2_alloc *al;
	unsigned int write_len = to - from;


	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
	error = gfs2_glock_nq_atime(&ip->i_gh);
	if (unlikely(error)) {
		if (error == GLR_TRYFAILED) {
			unlock_page(page);
			error = AOP_TRUNCATED_PAGE;
			yield();
		}
		goto out_uninit;
	}

	gfs2_write_calc_reserv(ip, write_len, &data_blocks, &ind_blocks);

	error = gfs2_write_alloc_required(ip, pos, write_len, &alloc_required);
	if (error)
		goto out_unlock;


	ip->i_alloc.al_requested = 0;
	if (alloc_required) {
		al = gfs2_alloc_get(ip);

		error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
		if (error)
			goto out_alloc_put;

		error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
		if (error)
			goto out_qunlock;

		al->al_requested = data_blocks + ind_blocks;
		error = gfs2_inplace_reserve(ip);
		if (error)
			goto out_qunlock;
	}

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;

	error = gfs2_trans_begin(sdp, rblocks, 0);
	if (error)
		goto out;

	if (gfs2_is_stuffed(ip)) {
		if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
			error = gfs2_unstuff_dinode(ip, page);
			if (error == 0)
				goto prepare_write;
		} else if (!PageUptodate(page))
			error = stuffed_readpage(ip, page);
		goto out;
	}

prepare_write:
	error = block_prepare_write(page, from, to, gfs2_get_block);

out:
	if (error) {
		gfs2_trans_end(sdp);
		if (alloc_required) {
			gfs2_inplace_release(ip);
out_qunlock:
			gfs2_quota_unlock(ip);
out_alloc_put:
			gfs2_alloc_put(ip);
		}
out_unlock:
		gfs2_glock_dq_m(1, &ip->i_gh);
out_uninit:
		gfs2_holder_uninit(&ip->i_gh);
	}

	return error;
}
コード例 #28
0
ファイル: dir.c プロジェクト: WiseMan787/ralink_sdk
/*
 * Read a directory, using filldir to fill the dirent memory.
 * smb_proc_readdir does the actual reading from the smb server.
 *
 * The cache code is almost directly taken from ncpfs
 */
static int 
smb_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
	struct dentry *dentry = filp->f_path.dentry;
	struct inode *dir = dentry->d_inode;
	struct smb_sb_info *server = server_from_dentry(dentry);
	union  smb_dir_cache *cache = NULL;
	struct smb_cache_control ctl;
	struct page *page = NULL;
	int result;

	ctl.page  = NULL;
	ctl.cache = NULL;

	VERBOSE("reading %s/%s, f_pos=%d\n",
		DENTRY_PATH(dentry),  (int) filp->f_pos);

	result = 0;

	lock_kernel();

	switch ((unsigned int) filp->f_pos) {
	case 0:
		if (filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR) < 0)
			goto out;
		filp->f_pos = 1;
		/* fallthrough */
	case 1:
		if (filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR) < 0)
			goto out;
		filp->f_pos = 2;
	}

	/*
	 * Make sure our inode is up-to-date.
	 */
	result = smb_revalidate_inode(dentry);
	if (result)
		goto out;


	page = grab_cache_page(&dir->i_data, 0);
	if (!page)
		goto read_really;

	ctl.cache = cache = kmap(page);
	ctl.head  = cache->head;

	if (!PageUptodate(page) || !ctl.head.eof) {
		VERBOSE("%s/%s, page uptodate=%d, eof=%d\n",
			 DENTRY_PATH(dentry), PageUptodate(page),ctl.head.eof);
		goto init_cache;
	}

	if (filp->f_pos == 2) {
		if (jiffies - ctl.head.time >= SMB_MAX_AGE(server))
			goto init_cache;

		/*
		 * N.B. ncpfs checks mtime of dentry too here, we don't.
		 *   1. common smb servers do not update mtime on dir changes
		 *   2. it requires an extra smb request
		 *      (revalidate has the same timeout as ctl.head.time)
		 *
		 * Instead smbfs invalidates its own cache on local changes
		 * and remote changes are not seen until timeout.
		 */
	}

	if (filp->f_pos > ctl.head.end)
		goto finished;

	ctl.fpos = filp->f_pos + (SMB_DIRCACHE_START - 2);
	ctl.ofs  = ctl.fpos / SMB_DIRCACHE_SIZE;
	ctl.idx  = ctl.fpos % SMB_DIRCACHE_SIZE;

	for (;;) {
		if (ctl.ofs != 0) {
			ctl.page = find_lock_page(&dir->i_data, ctl.ofs);
			if (!ctl.page)
				goto invalid_cache;
			ctl.cache = kmap(ctl.page);
			if (!PageUptodate(ctl.page))
				goto invalid_cache;
		}
		while (ctl.idx < SMB_DIRCACHE_SIZE) {
			struct dentry *dent;
			int res;

			dent = smb_dget_fpos(ctl.cache->dentry[ctl.idx],
					     dentry, filp->f_pos);
			if (!dent)
				goto invalid_cache;

			res = filldir(dirent, dent->d_name.name,
				      dent->d_name.len, filp->f_pos,
				      dent->d_inode->i_ino, DT_UNKNOWN);
			dput(dent);
			if (res)
				goto finished;
			filp->f_pos += 1;
			ctl.idx += 1;
			if (filp->f_pos > ctl.head.end)
				goto finished;
		}
		if (ctl.page) {
			kunmap(ctl.page);
			SetPageUptodate(ctl.page);
			unlock_page(ctl.page);
			page_cache_release(ctl.page);
			ctl.page = NULL;
		}
		ctl.idx  = 0;
		ctl.ofs += 1;
	}
invalid_cache:
	if (ctl.page) {
		kunmap(ctl.page);
		unlock_page(ctl.page);
		page_cache_release(ctl.page);
		ctl.page = NULL;
	}
	ctl.cache = cache;
init_cache:
	smb_invalidate_dircache_entries(dentry);
	ctl.head.time = jiffies;
	ctl.head.eof = 0;
	ctl.fpos = 2;
	ctl.ofs = 0;
	ctl.idx = SMB_DIRCACHE_START;
	ctl.filled = 0;
	ctl.valid  = 1;
read_really:
	result = server->ops->readdir(filp, dirent, filldir, &ctl);
	if (result == -ERESTARTSYS && page)
		ClearPageUptodate(page);
	if (ctl.idx == -1)
		goto invalid_cache;	/* retry */
	ctl.head.end = ctl.fpos - 1;
	ctl.head.eof = ctl.valid;
finished:
	if (page) {
		cache->head = ctl.head;
		kunmap(page);
		if (result != -ERESTARTSYS)
			SetPageUptodate(page);
		unlock_page(page);
		page_cache_release(page);
	}
	if (ctl.page) {
		kunmap(ctl.page);
		SetPageUptodate(ctl.page);
		unlock_page(ctl.page);
		page_cache_release(ctl.page);
	}
out:
	unlock_kernel();
	return result;
}
コード例 #29
0
ファイル: data.c プロジェクト: aejsmith/linux
struct page *get_read_data_page(struct inode *inode, pgoff_t index, int rw)
{
    struct address_space *mapping = inode->i_mapping;
    struct dnode_of_data dn;
    struct page *page;
    struct extent_info ei;
    int err;
    struct f2fs_io_info fio = {
        .sbi = F2FS_I_SB(inode),
        .type = DATA,
        .rw = rw,
        .encrypted_page = NULL,
    };

    if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
        return read_mapping_page(mapping, index, NULL);

    page = grab_cache_page(mapping, index);
    if (!page)
        return ERR_PTR(-ENOMEM);

    if (f2fs_lookup_extent_cache(inode, index, &ei)) {
        dn.data_blkaddr = ei.blk + index - ei.fofs;
        goto got_it;
    }

    set_new_dnode(&dn, inode, NULL, NULL, 0);
    err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
    if (err)
        goto put_err;
    f2fs_put_dnode(&dn);

    if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
        err = -ENOENT;
        goto put_err;
    }
got_it:
    if (PageUptodate(page)) {
        unlock_page(page);
        return page;
    }

    /*
     * A new dentry page is allocated but not able to be written, since its
     * new inode page couldn't be allocated due to -ENOSPC.
     * In such the case, its blkaddr can be remained as NEW_ADDR.
     * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
     */
    if (dn.data_blkaddr == NEW_ADDR) {
        zero_user_segment(page, 0, PAGE_CACHE_SIZE);
        SetPageUptodate(page);
        unlock_page(page);
        return page;
    }

    fio.blk_addr = dn.data_blkaddr;
    fio.page = page;
    err = f2fs_submit_page_bio(&fio);
    if (err)
        goto put_err;
    return page;

put_err:
    f2fs_put_page(page, 1);
    return ERR_PTR(err);
}
コード例 #30
0
static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
					      struct inode *inode,
					      unsigned flags)
{
	int ret, needed_blocks;
	handle_t *handle = NULL;
	int retries = 0, sem_held = 0;
	struct page *page = NULL;
	unsigned from, to;
	struct ext4_iloc iloc;

	if (!ext4_has_inline_data(inode)) {
		/*
		 * clear the flag so that no new write
		 * will trap here again.
		 */
		ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
		return 0;
	}

	needed_blocks = ext4_writepage_trans_blocks(inode);

	ret = ext4_get_inode_loc(inode, &iloc);
	if (ret)
		return ret;

retry:
	handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
	if (IS_ERR(handle)) {
		ret = PTR_ERR(handle);
		handle = NULL;
		goto out;
	}

	/* We cannot recurse into the filesystem as the transaction is already
	 * started */
	flags |= AOP_FLAG_NOFS;

	page = grab_cache_page_write_begin(mapping, 0, flags);
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}

	down_write(&EXT4_I(inode)->xattr_sem);
	sem_held = 1;
	/* If some one has already done this for us, just exit. */
	if (!ext4_has_inline_data(inode)) {
		ret = 0;
		goto out;
	}

	from = 0;
	to = ext4_get_inline_size(inode);
	if (!PageUptodate(page)) {
		ret = ext4_read_inline_page(inode, page);
		if (ret < 0)
			goto out;
	}

	ret = ext4_destroy_inline_data_nolock(handle, inode);
	if (ret)
		goto out;

	if (ext4_should_dioread_nolock(inode))
		ret = __block_write_begin(page, from, to, ext4_get_block_write);
	else
		ret = __block_write_begin(page, from, to, ext4_get_block);

	if (!ret && ext4_should_journal_data(inode)) {
		ret = ext4_walk_page_buffers(handle, page_buffers(page),
					     from, to, NULL,
					     do_journal_get_write_access);
	}

	if (ret) {
		unlock_page(page);
		page_cache_release(page);
		ext4_orphan_add(handle, inode);
		up_write(&EXT4_I(inode)->xattr_sem);
		sem_held = 0;
		ext4_journal_stop(handle);
		handle = NULL;
		ext4_truncate_failed_write(inode);
		/*
		 * If truncate failed early the inode might
		 * still be on the orphan list; we need to
		 * make sure the inode is removed from the
		 * orphan list in that case.
		 */
		if (inode->i_nlink)
			ext4_orphan_del(NULL, inode);
	}

	if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
		goto retry;

	block_commit_write(page, from, to);
out:
	if (page) {
		unlock_page(page);
		page_cache_release(page);
	}
	if (sem_held)
		up_write(&EXT4_I(inode)->xattr_sem);
	if (handle)
		ext4_journal_stop(handle);
	brelse(iloc.bh);
	return ret;
}