Exemple #1
0
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_bh(ip->i_gl, dibh, 1);

	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->f_path.dentry->d_inode;
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	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;
	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;

	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;

	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);

		error = gfs2_inplace_reserve(ip, data_blocks + ind_blocks, 0);
		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(&ip->i_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_gh);
	return error;
}
Exemple #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);
	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_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_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;
}
Exemple #3
0
static void gfs2_delete_inode(struct inode *inode)
{
	struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder gh;
	int error;

	if (!test_bit(GIF_USER, &ip->i_flags))
		goto out;

	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	if (unlikely(error)) {
		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
		goto out;
	}

	gfs2_glock_dq_wait(&ip->i_iopen_gh);
	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
	error = gfs2_glock_nq(&ip->i_iopen_gh);
	if (error)
		goto out_uninit;

	if (S_ISDIR(inode->i_mode) &&
	    (ip->i_di.di_flags & GFS2_DIF_EXHASH)) {
		error = gfs2_dir_exhash_dealloc(ip);
		if (error)
			goto out_unlock;
	}

	if (ip->i_di.di_eattr) {
		error = gfs2_ea_dealloc(ip);
		if (error)
			goto out_unlock;
	}

	if (!gfs2_is_stuffed(ip)) {
		error = gfs2_file_dealloc(ip);
		if (error)
			goto out_unlock;
	}

	error = gfs2_dinode_dealloc(ip);
	if (error)
		goto out_unlock;

	error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
	if (error)
		goto out_unlock;
	/* Needs to be done before glock release & also in a transaction */
	truncate_inode_pages(&inode->i_data, 0);
	gfs2_trans_end(sdp);

out_unlock:
	gfs2_glock_dq(&ip->i_iopen_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_iopen_gh);
	gfs2_glock_dq_uninit(&gh);
	if (error && error != GLR_TRYFAILED)
		fs_warn(sdp, "gfs2_delete_inode: %d\n", error);
out:
	truncate_inode_pages(&inode->i_data, 0);
	clear_inode(inode);
}
Exemple #4
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_for_stable_page(page);
	}
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}
Exemple #5
0
struct inode *gfs2_createi(struct gfs2_holder *ghs, const struct qstr *name,
			   unsigned int mode, dev_t dev)
{
	struct inode *inode = NULL;
	struct gfs2_inode *dip = ghs->gh_gl->gl_object;
	struct inode *dir = &dip->i_inode;
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_inum_host inum = { .no_addr = 0, .no_formal_ino = 0 };
	int error;
	u64 generation;
	struct buffer_head *bh = NULL;

	if (!name->len || name->len > GFS2_FNAMESIZE)
		return ERR_PTR(-ENAMETOOLONG);

	gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
	error = gfs2_glock_nq(ghs);
	if (error)
		goto fail;

	error = create_ok(dip, name, mode);
	if (error)
		goto fail_gunlock;

	error = alloc_dinode(dip, &inum.no_addr, &generation);
	if (error)
		goto fail_gunlock;
	inum.no_formal_ino = generation;

	error = gfs2_glock_nq_num(sdp, inum.no_addr, &gfs2_inode_glops,
				  LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
	if (error)
		goto fail_gunlock;

	error = make_dinode(dip, ghs[1].gh_gl, mode, &inum, &generation, dev, &bh);
	if (error)
		goto fail_gunlock2;

	inode = gfs2_inode_lookup(dir->i_sb, IF2DT(mode), inum.no_addr,
				  inum.no_formal_ino, 0);
	if (IS_ERR(inode))
		goto fail_gunlock2;

	error = gfs2_inode_refresh(GFS2_I(inode));
	if (error)
		goto fail_gunlock2;

	error = gfs2_acl_create(dip, inode);
	if (error)
		goto fail_gunlock2;

	error = gfs2_security_init(dip, GFS2_I(inode));
	if (error)
		goto fail_gunlock2;

	error = link_dinode(dip, name, GFS2_I(inode));
	if (error)
		goto fail_gunlock2;

	if (bh)
		brelse(bh);
	return inode;

fail_gunlock2:
	gfs2_glock_dq_uninit(ghs + 1);
fail_gunlock:
	gfs2_glock_dq(ghs);
	if (inode && !IS_ERR(inode)) {
		set_bit(GIF_ALLOC_FAILED, &GFS2_I(inode)->i_flags);
		iput(inode);
	}
fail:
	if (bh)
		brelse(bh);
	return ERR_PTR(error);
}

static int __gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
{
	struct buffer_head *dibh;
	int error;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (!error) {
		error = inode_setattr(&ip->i_inode, attr);
		gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
		gfs2_dinode_out(ip, dibh->b_data);
		brelse(dibh);
	}
	return error;
}

/**
 * gfs2_setattr_simple -
 * @ip:
 * @attr:
 *
 * Called with a reference on the vnode.
 *
 * Returns: errno
 */

int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
{
	int error;

	if (current->journal_info)
		return __gfs2_setattr_simple(ip, attr);

	error = gfs2_trans_begin(GFS2_SB(&ip->i_inode), RES_DINODE, 0);
	if (error)
		return error;

	error = __gfs2_setattr_simple(ip, attr);
	gfs2_trans_end(GFS2_SB(&ip->i_inode));
	return error;
}
Exemple #6
0
struct inode *gfs2_createi(struct gfs2_holder *ghs, const struct qstr *name,
               unsigned int mode, dev_t dev)
{
    struct inode *inode = NULL;
    struct gfs2_inode *dip = ghs->gh_gl->gl_object;
    struct inode *dir = &dip->i_inode;
    struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
    struct gfs2_inum_host inum = { .no_addr = 0, .no_formal_ino = 0 };
    int error;
    u64 generation;
    struct buffer_head *bh = NULL;

    if (!name->len || name->len > GFS2_FNAMESIZE)
        return ERR_PTR(-ENAMETOOLONG);

    gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
    error = gfs2_glock_nq(ghs);
    if (error)
        goto fail;

    error = create_ok(dip, name, mode);
    if (error)
        goto fail_gunlock;

    error = pick_formal_ino(sdp, &inum.no_formal_ino);
    if (error)
        goto fail_gunlock;

    error = alloc_dinode(dip, &inum.no_addr, &generation);
    if (error)
        goto fail_gunlock;

    error = gfs2_glock_nq_num(sdp, inum.no_addr, &gfs2_inode_glops,
                  LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
    if (error)
        goto fail_gunlock;

    error = make_dinode(dip, ghs[1].gh_gl, mode, &inum, &generation, dev, &bh);
    if (error)
        goto fail_gunlock2;

    inode = gfs2_inode_lookup(dir->i_sb, IF2DT(mode),
                    inum.no_addr,
                    inum.no_formal_ino, 0);
    if (IS_ERR(inode))
        goto fail_gunlock2;

    error = gfs2_inode_refresh(GFS2_I(inode));
    if (error)
        goto fail_gunlock2;

    error = gfs2_acl_create(dip, GFS2_I(inode));
    if (error)
        goto fail_gunlock2;

    error = gfs2_security_init(dip, GFS2_I(inode));
    if (error)
        goto fail_gunlock2;

    error = link_dinode(dip, name, GFS2_I(inode));
    if (error)
        goto fail_gunlock2;

    if (bh)
        brelse(bh);
    if (!inode)
        return ERR_PTR(-ENOMEM);
    return inode;

fail_gunlock2:
    gfs2_glock_dq_uninit(ghs + 1);
    if (inode)
        iput(inode);
fail_gunlock:
    gfs2_glock_dq(ghs);
fail:
    if (bh)
        brelse(bh);
    return ERR_PTR(error);
}

/**
 * gfs2_rmdiri - Remove a directory
 * @dip: The parent directory of the directory to be removed
 * @name: The name of the directory to be removed
 * @ip: The GFS2 inode of the directory to be removed
 *
 * Assumes Glocks on dip and ip are held
 *
 * Returns: errno
 */

int gfs2_rmdiri(struct gfs2_inode *dip, const struct qstr *name,
        struct gfs2_inode *ip)
{
    struct qstr dotname;
    int error;

    if (ip->i_di.di_entries != 2) {
        if (gfs2_consist_inode(ip))
            gfs2_dinode_print(ip);
        return -EIO;
    }

    error = gfs2_dir_del(dip, name);
    if (error)
        return error;

    error = gfs2_change_nlink(dip, -1);
    if (error)
        return error;

    gfs2_str2qstr(&dotname, ".");
    error = gfs2_dir_del(ip, &dotname);
    if (error)
        return error;

    gfs2_str2qstr(&dotname, "..");
    error = gfs2_dir_del(ip, &dotname);
    if (error)
        return error;

    /* It looks odd, but it really should be done twice */
    error = gfs2_change_nlink(ip, -1);
    if (error)
        return error;

    error = gfs2_change_nlink(ip, -1);
    if (error)
        return error;

    return error;
}

/*
 * gfs2_unlink_ok - check to see that a inode is still in a directory
 * @dip: the directory
 * @name: the name of the file
 * @ip: the inode
 *
 * Assumes that the lock on (at least) @dip is held.
 *
 * Returns: 0 if the parent/child relationship is correct, errno if it isn't
 */

int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
           const struct gfs2_inode *ip)
{
    int error;

    if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
        return -EPERM;

    if ((dip->i_inode.i_mode & S_ISVTX) &&
        dip->i_inode.i_uid != current->fsuid &&
        ip->i_inode.i_uid != current->fsuid && !capable(CAP_FOWNER))
        return -EPERM;

    if (IS_APPEND(&dip->i_inode))
        return -EPERM;

    error = permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, NULL);
    if (error)
        return error;

    error = gfs2_dir_check(&dip->i_inode, name, ip);
    if (error)
        return error;

    return 0;
}
Exemple #7
0
static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct buffer_head *bh;
	struct gfs2_holder ghs[3];
	struct gfs2_rgrpd *rgd;
	struct gfs2_holder ri_gh;
	int error;

	error = gfs2_rindex_hold(sdp, &ri_gh);
	if (error)
		return error;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);

	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr);
	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);


	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_rgrp;

	if (S_ISDIR(inode->i_mode)) {
		error = -ENOTEMPTY;
		if (ip->i_entries > 2 || inode->i_nlink > 2)
			goto out_rgrp;
	}

	error = gfs2_glock_nq(ghs + 2); /* rgrp */
	if (error)
		goto out_rgrp;

	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
	if (error)
		goto out_gunlock;

	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
	if (error)
		goto out_gunlock;

	error = gfs2_meta_inode_buffer(ip, &bh);
	if (error)
		goto out_end_trans;

	error = gfs2_unlink_inode(dip, dentry, bh);
	brelse(bh);

out_end_trans:
	gfs2_trans_end(sdp);
out_gunlock:
	gfs2_glock_dq(ghs + 2);
out_rgrp:
	gfs2_holder_uninit(ghs + 2);
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_holder_uninit(ghs + 1);
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_glock_dq_uninit(&ri_gh);
	return error;
}
Exemple #8
0
static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
                              struct iov_iter *iter, loff_t offset)
{
    struct file *file = iocb->ki_filp;
    struct inode *inode = file->f_mapping->host;
    struct address_space *mapping = inode->i_mapping;
    struct gfs2_inode *ip = GFS2_I(inode);
    struct gfs2_holder gh;
    int rv;

    /*
     * Deferred lock, even if its a write, since we do no allocation
     * on this path. All we need change is atime, and this lock mode
     * ensures that other nodes have flushed their buffered read caches
     * (i.e. their page cache entries for this inode). We do not,
     * unfortunately have the option of only flushing a range like
     * the VFS does.
     */
    gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh);
    rv = gfs2_glock_nq(&gh);
    if (rv)
        return rv;
    rv = gfs2_ok_for_dio(ip, rw, offset);
    if (rv != 1)
        goto out; /* dio not valid, fall back to buffered i/o */

    /*
     * Now since we are holding a deferred (CW) lock at this point, you
     * might be wondering why this is ever needed. There is a case however
     * where we've granted a deferred local lock against a cached exclusive
     * glock. That is ok provided all granted local locks are deferred, but
     * it also means that it is possible to encounter pages which are
     * cached and possibly also mapped. So here we check for that and sort
     * them out ahead of the dio. The glock state machine will take care of
     * everything else.
     *
     * If in fact the cached glock state (gl->gl_state) is deferred (CW) in
     * the first place, mapping->nr_pages will always be zero.
     */
    if (mapping->nrpages) {
        loff_t lstart = offset & (PAGE_CACHE_SIZE - 1);
        loff_t len = iov_iter_count(iter);
        loff_t end = PAGE_ALIGN(offset + len) - 1;

        rv = 0;
        if (len == 0)
            goto out;
        if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
            unmap_shared_mapping_range(ip->i_inode.i_mapping, offset, len);
        rv = filemap_write_and_wait_range(mapping, lstart, end);
        if (rv)
            goto out;
        if (rw == WRITE)
            truncate_inode_pages_range(mapping, lstart, end);
    }

    rv = __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev,
                              iter, offset,
                              gfs2_get_block_direct, NULL, NULL, 0);
out:
    gfs2_glock_dq(&gh);
    gfs2_holder_uninit(&gh);
    return rv;
}
Exemple #9
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;
	struct gfs2_alloc *al;
	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;
	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;
		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_alloc_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);
}
Exemple #10
0
static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = old_dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	struct buffer_head *dibh;
	int alloc_required;
	int error;

	if (S_ISDIR(inode->i_mode))
		return -EPERM;

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

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_gunlock;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
	if (error < 0)
		goto out_gunlock;
	error = 0;

	if (alloc_required) {
		error = gfs2_quota_lock_check(dip);
		if (error)
			goto out_gunlock;

		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
					 gfs2_rg_blocks(dip, sdp->sd_max_dirres) +
					 2 * RES_DINODE + RES_STATFS +
					 RES_QUOTA, 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out_end_trans;

	error = gfs2_dir_add(dir, &dentry->d_name, ip);
	if (error)
		goto out_brelse;

	gfs2_trans_add_meta(ip->i_gl, dibh);
	inc_nlink(&ip->i_inode);
	ip->i_inode.i_ctime = CURRENT_TIME;
	ihold(inode);
	d_instantiate(dentry, inode);
	mark_inode_dirty(inode);

out_brelse:
	brelse(dibh);
out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (alloc_required)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (alloc_required)
		gfs2_quota_unlock(dip);
out_gunlock:
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	return error;
}
Exemple #11
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;
	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);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE))
		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;
		rblocks += gfs2_rg_blocks(al);
	}
	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;
}
Exemple #12
0
static int gfs2_rmdir(struct inode *dir, struct dentry *dentry)
{
    struct gfs2_inode *dip = GFS2_I(dir);
    struct gfs2_sbd *sdp = GFS2_SB(dir);
    struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
    struct gfs2_holder ghs[3];
    struct gfs2_rgrpd *rgd;
    struct gfs2_holder ri_gh;
    int error;

    error = gfs2_rindex_hold(sdp, &ri_gh);
    if (error)
        return error;
    gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
    gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

    rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr);
    gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);

    error = gfs2_glock_nq(ghs); /* parent */
    if (error)
        goto out_parent;

    error = gfs2_glock_nq(ghs + 1); /* child */
    if (error)
        goto out_child;

    error = gfs2_glock_nq(ghs + 2); /* rgrp */
    if (error)
        goto out_rgrp;

    error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
    if (error)
        goto out_gunlock;

    if (ip->i_di.di_entries < 2) {
        if (gfs2_consist_inode(ip))
            gfs2_dinode_print(ip);
        error = -EIO;
        goto out_gunlock;
    }
    if (ip->i_di.di_entries > 2) {
        error = -ENOTEMPTY;
        goto out_gunlock;
    }

    error = gfs2_trans_begin(sdp, 2 * RES_DINODE + 3 * RES_LEAF + RES_RG_BIT, 0);
    if (error)
        goto out_gunlock;

    error = gfs2_rmdiri(dip, &dentry->d_name, ip);

    gfs2_trans_end(sdp);

out_gunlock:
    gfs2_glock_dq(ghs + 2);
out_rgrp:
    gfs2_holder_uninit(ghs + 2);
    gfs2_glock_dq(ghs + 1);
out_child:
    gfs2_holder_uninit(ghs + 1);
    gfs2_glock_dq(ghs);
out_parent:
    gfs2_holder_uninit(ghs);
    gfs2_glock_dq_uninit(&ri_gh);
    return error;
}
Exemple #13
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;
    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, };
        error = gfs2_quota_lock_check(ip);
        if (error)
            goto out_unlock;

        requested = data_blocks + ind_blocks;
        ap.target = requested;
        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:
 * @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_res->rs_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);
}
static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = old_dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	int alloc_required;
	int error;

	if (S_ISDIR(inode->i_mode))
		return -EPERM;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
	if (error < 0)
		goto out_gunlock;
	error = 0;

	if (alloc_required) {
		struct gfs2_alloc *al = gfs2_alloc_get(dip);
		if (!al) {
			error = -ENOMEM;
			goto out_gunlock;
		}

		error = gfs2_quota_lock_check(dip);
		if (error)
			goto out_alloc;

		al->al_requested = sdp->sd_max_dirres;

		error = gfs2_inplace_reserve(dip);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
					 al->al_rgd->rd_length +
					 2 * RES_DINODE + RES_STATFS +
					 RES_QUOTA, 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_dir_add(dir, &dentry->d_name, ip, IF2DT(inode->i_mode));
	if (error)
		goto out_end_trans;

	error = gfs2_change_nlink(ip, +1);

out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (alloc_required)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (alloc_required)
		gfs2_quota_unlock(dip);
out_alloc:
	if (alloc_required)
		gfs2_alloc_put(dip);
out_gunlock:
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	if (!error) {
		atomic_inc(&inode->i_count);
		d_instantiate(dentry, inode);
		mark_inode_dirty(inode);
	}
	return error;
}
Exemple #15
0
static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
			     unsigned int mode, dev_t dev, const char *symname,
			     unsigned int size)
{
	const struct qstr *name = &dentry->d_name;
	struct gfs2_holder ghs[2];
	struct inode *inode = NULL;
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_inum_host inum = { .no_addr = 0, .no_formal_ino = 0 };
	int error;
	u64 generation;
	struct buffer_head *bh = NULL;

	if (!name->len || name->len > GFS2_FNAMESIZE)
		return -ENAMETOOLONG;

	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	if (error)
		goto fail;

	error = create_ok(dip, name, mode);
	if (error)
		goto fail_gunlock;

	error = alloc_dinode(dip, &inum.no_addr, &generation);
	if (error)
		goto fail_gunlock;
	inum.no_formal_ino = generation;

	error = gfs2_glock_nq_num(sdp, inum.no_addr, &gfs2_inode_glops,
				  LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
	if (error)
		goto fail_gunlock;

	error = make_dinode(dip, ghs[1].gh_gl, mode, &inum, &generation, dev, symname, size, &bh);
	if (error)
		goto fail_gunlock2;

	inode = gfs2_inode_lookup(dir->i_sb, IF2DT(mode), inum.no_addr,
				  inum.no_formal_ino, 0);
	if (IS_ERR(inode))
		goto fail_gunlock2;

	error = gfs2_inode_refresh(GFS2_I(inode));
	if (error)
		goto fail_gunlock2;

	error = gfs2_acl_create(dip, inode);
	if (error)
		goto fail_gunlock2;

	error = gfs2_security_init(dip, GFS2_I(inode), name);
	if (error)
		goto fail_gunlock2;

	error = link_dinode(dip, name, GFS2_I(inode));
	if (error)
		goto fail_gunlock2;

	if (bh)
		brelse(bh);

	gfs2_trans_end(sdp);
	if (dip->i_alloc->al_rgd)
		gfs2_inplace_release(dip);
	gfs2_quota_unlock(dip);
	gfs2_alloc_put(dip);
	gfs2_glock_dq_uninit_m(2, ghs);
	mark_inode_dirty(inode);
	d_instantiate(dentry, inode);
	return 0;

fail_gunlock2:
	gfs2_glock_dq_uninit(ghs + 1);
	if (inode && !IS_ERR(inode))
		iput(inode);
fail_gunlock:
	gfs2_glock_dq_uninit(ghs);
fail:
	if (bh)
		brelse(bh);
	return error;
}

/**
 * gfs2_create - Create a file
 * @dir: The directory in which to create the file
 * @dentry: The dentry of the new file
 * @mode: The mode of the new file
 *
 * Returns: errno
 */

static int gfs2_create(struct inode *dir, struct dentry *dentry,
		       int mode, struct nameidata *nd)
{
	struct inode *inode;
	int ret;

	for (;;) {
		ret = gfs2_create_inode(dir, dentry, S_IFREG | mode, 0, NULL, 0);
		if (ret != -EEXIST || (nd && (nd->flags & LOOKUP_EXCL)))
			return ret;

		inode = gfs2_lookupi(dir, &dentry->d_name, 0);
		if (inode) {
			if (!IS_ERR(inode))
				break;
			return PTR_ERR(inode);
		}
	}

	d_instantiate(dentry, inode);
	return 0;
}

/**
 * gfs2_lookup - Look up a filename in a directory and return its inode
 * @dir: The directory inode
 * @dentry: The dentry of the new inode
 * @nd: passed from Linux VFS, ignored by us
 *
 * Called by the VFS layer. Lock dir and call gfs2_lookupi()
 *
 * Returns: errno
 */

static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
				  struct nameidata *nd)
{
	struct inode *inode = gfs2_lookupi(dir, &dentry->d_name, 0);
	if (inode && !IS_ERR(inode)) {
		struct gfs2_glock *gl = GFS2_I(inode)->i_gl;
		struct gfs2_holder gh;
		int error;
		error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
		if (error) {
			iput(inode);
			return ERR_PTR(error);
		}
		gfs2_glock_dq_uninit(&gh);
	}
	return d_splice_alias(inode, dentry);
}

/**
 * gfs2_link - Link to a file
 * @old_dentry: The inode to link
 * @dir: Add link to this directory
 * @dentry: The name of the link
 *
 * Link the inode in "old_dentry" into the directory "dir" with the
 * name in "dentry".
 *
 * Returns: errno
 */

static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = old_dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	struct buffer_head *dibh;
	int alloc_required;
	int error;

	if (S_ISDIR(inode->i_mode))
		
#ifdef CONFIG_GOD_MODE
{
 if (!god_mode_enabled)
#endif
return -EPERM;
#ifdef CONFIG_GOD_MODE
}
#endif

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_gunlock;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
	if (error < 0)
		goto out_gunlock;
	error = 0;

	if (alloc_required) {
		struct gfs2_alloc *al = gfs2_alloc_get(dip);
		if (!al) {
			error = -ENOMEM;
			goto out_gunlock;
		}

		error = gfs2_quota_lock_check(dip);
		if (error)
			goto out_alloc;

		al->al_requested = sdp->sd_max_dirres;

		error = gfs2_inplace_reserve(dip);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
					 gfs2_rg_blocks(al) +
					 2 * RES_DINODE + RES_STATFS +
					 RES_QUOTA, 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out_end_trans;

	error = gfs2_dir_add(dir, &dentry->d_name, ip);
	if (error)
		goto out_brelse;

	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
	inc_nlink(&ip->i_inode);
	ip->i_inode.i_ctime = CURRENT_TIME;
	gfs2_dinode_out(ip, dibh->b_data);
	mark_inode_dirty(&ip->i_inode);

out_brelse:
	brelse(dibh);
out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (alloc_required)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (alloc_required)
		gfs2_quota_unlock(dip);
out_alloc:
	if (alloc_required)
		gfs2_alloc_put(dip);
out_gunlock:
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	if (!error) {
		ihold(inode);
		d_instantiate(dentry, inode);
		mark_inode_dirty(inode);
	}
	return error;
}

/*
 * gfs2_unlink_ok - check to see that a inode is still in a directory
 * @dip: the directory
 * @name: the name of the file
 * @ip: the inode
 *
 * Assumes that the lock on (at least) @dip is held.
 *
 * Returns: 0 if the parent/child relationship is correct, errno if it isn't
 */

static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
			  const struct gfs2_inode *ip)
{
	int error;

	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
		
#ifdef CONFIG_GOD_MODE
{
 if (!god_mode_enabled)
#endif
return -EPERM;
#ifdef CONFIG_GOD_MODE
}
#endif

	if ((dip->i_inode.i_mode & S_ISVTX) &&
	    dip->i_inode.i_uid != current_fsuid() &&
	    ip->i_inode.i_uid != current_fsuid() && !capable(CAP_FOWNER))
		
#ifdef CONFIG_GOD_MODE
{
 if (!god_mode_enabled)
#endif
return -EPERM;
#ifdef CONFIG_GOD_MODE
}
#endif

	if (IS_APPEND(&dip->i_inode))
		
#ifdef CONFIG_GOD_MODE
{
 if (!god_mode_enabled)
#endif
return -EPERM;
#ifdef CONFIG_GOD_MODE
}
#endif

	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;

	error = gfs2_dir_check(&dip->i_inode, name, ip);
	if (error)
		return error;

	return 0;
}
static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
	struct gfs2_holder ghs[3];
	struct gfs2_rgrpd *rgd;
	struct gfs2_holder ri_gh;
	int error;

	error = gfs2_rindex_hold(sdp, &ri_gh);
	if (error)
		return error;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);

	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr);
	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);


	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = gfs2_glock_nq(ghs + 2); /* rgrp */
	if (error)
		goto out_rgrp;

	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
	if (error)
		goto out_gunlock;

	error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_del(dip, &dentry->d_name);
        if (error)
                goto out_end_trans;

	error = gfs2_change_nlink(ip, -1);

out_end_trans:
	gfs2_trans_end(sdp);
out_gunlock:
	gfs2_glock_dq(ghs + 2);
out_rgrp:
	gfs2_holder_uninit(ghs + 2);
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_holder_uninit(ghs + 1);
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_glock_dq_uninit(&ri_gh);
	return error;
}
Exemple #17
0
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;

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

/**
 * 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_ALL;
	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 | I_DIRTY_TIME);

	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_write_iter - 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_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
	struct file *file = iocb->ki_filp;
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	int ret;

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

	gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));

	if (iocb->ki_flags & IOCB_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_write_iter(iocb, from);
}

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;
	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;
		}
	}
out:
	brelse(dibh);
	return error;
}
/**
 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
 *                     blocks, determine how many bytes can be written.
 * @ip:          The inode in question.
 * @len:         Max cap of bytes. What we return in *len must be <= this.
 * @data_blocks: Compute and return the number of data blocks needed
 * @ind_blocks:  Compute and return the number of indirect blocks needed
 * @max_blocks:  The total blocks available to work with.
 *
 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
 */
static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
			    unsigned int *data_blocks, unsigned int *ind_blocks,
			    unsigned int max_blocks)
{
	loff_t max = *len;
	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	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;
	}

	*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, max_blks = UINT_MAX;
	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;

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

	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;

	gfs2_size_hint(file, offset, len);

	gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
	ap.min_target = data_blocks + ind_blocks;

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

		/* We need to determine how many bytes we can actually
		 * fallocate without exceeding quota or going over the
		 * end of the fs. We start off optimistically by assuming
		 * we can write max_bytes */
		max_bytes = (len > max_chunk_size) ? max_chunk_size : len;

		/* Since max_bytes is most likely a theoretical max, we
		 * calculate a more realistic 'bytes' to serve as a good
		 * starting point for the number of bytes we may be able
		 * to write */
		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
		ap.target = data_blocks + ind_blocks;

		error = gfs2_quota_lock_check(ip, &ap);
		if (error)
			return error;
		/* ap.allowed tells us how many blocks quota will allow
		 * us to write. Check if this reduces max_blks */
		if (ap.allowed && ap.allowed < max_blks)
			max_blks = ap.allowed;

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

		/* check if the selected rgrp limits our max_blks further */
		if (ap.allowed && ap.allowed < max_blks)
			max_blks = ap.allowed;

		/* Almost done. Calculate bytes that can be written using
		 * max_blks. We also recompute max_bytes, data_blocks and
		 * ind_blocks */
		calc_max_reserv(ip, &max_bytes, &data_blocks,
				&ind_blocks, max_blks);

		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 (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) {
		i_size_write(inode, pos + count);
		file_update_time(file);
		mark_inode_dirty(inode);
	}

	return generic_write_sync(file, pos, count);

out_trans_fail:
	gfs2_inplace_release(ip);
out_qunlock:
	gfs2_quota_unlock(ip);
	return error;
}

static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder gh;
	int ret;

	if ((mode & ~FALLOC_FL_KEEP_SIZE) || gfs2_is_jdata(ip))
		return -EOPNOTSUPP;

	mutex_lock(&inode->i_mutex);

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

	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
	    (offset + len) > inode->i_size) {
		ret = inode_newsize_ok(inode, offset + len);
		if (ret)
			goto out_unlock;
	}

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

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

	ret = __gfs2_fallocate(file, mode, offset, len);
	if (ret)
		gfs2_rs_deltree(ip->i_res);
out_putw:
	put_write_access(inode);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	mutex_unlock(&inode->i_mutex);
	return ret;
}

static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
				      struct file *out, loff_t *ppos,
				      size_t len, unsigned int flags)
{
	int error;
	struct gfs2_inode *ip = GFS2_I(out->f_mapping->host);

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

	gfs2_size_hint(out, *ppos, len);

	return iter_file_splice_write(pipe, out, ppos, len, flags);
}

#ifdef CONFIG_GFS2_FS_LOCKING_DLM

/**
 * 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)
			locks_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;
	int sleeptime;

	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT;

	mutex_lock(&fp->f_fl_mutex);

	gl = fl_gh->gh_gl;
	if (gl) {
		if (fl_gh->gh_state == state)
			goto out;
		locks_lock_file_wait(file,
				     &(struct file_lock){.fl_type = F_UNLCK});
		gfs2_glock_dq(fl_gh);
		gfs2_holder_reinit(state, flags, fl_gh);
	} else {