示例#1
0
static int
_stp_proc_open_file(struct inode *inode, struct file *filp)
{
	struct stap_procfs_probe *spp;
	int res;

	spp = (struct stap_procfs_probe *)PDE(inode)->data;
	if (spp == NULL) {
		return -EINVAL;
	}

	res = generic_file_open(inode, filp);
	if (res)
		return res;

	/* To avoid concurrency problems, we only allow 1 open at a
	 * time. */

	_spp_lock(spp);

	/* If the file isn't open yet, ... */
	if (spp->opencount == 0) {
		res = 0;
	}
	/* If open() was called with O_NONBLOCK, don't block, just
	 * return EAGAIN. */
	else if (filp->f_flags & O_NONBLOCK) {
		res = -EAGAIN;
	}
	/* The file is already open, so wait. */
	else {
		for (res = 0;;) {
			if (spp->opencount == 0) {
				res = 0;
				break;
			}
			_spp_unlock(spp);
			res = wait_event_interruptible(spp->waitq,
						       spp->opencount == 0);
			_spp_lock(spp);
			if (res < 0)
				break;
		}
	}
	if (likely(res == 0)) {
		spp->opencount++;
		filp->private_data = spp;
		if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
			spp->buffer[0] = '\0';
			spp->count = 0;
			spp->needs_fill = 1;
		}
	}

	_spp_unlock(spp);
	return 0;
}
示例#2
0
文件: file.c 项目: mnv104/capfs
/* capfs_open()
 *
 * Called from fs/open.c:filep_open()
 *
 * NOTES:
 * Truncation and creation are handled by fs/namei.c:open_namei()
 * We need to take care of O_APPEND here.
 *
 * The inode for the file is not necessarily up to date.  This is
 * important in the O_APPEND case because we need to have the most
 * recent size, so we're going to force a revalidate_inode() in the case
 * of an append.
 */
int capfs_open(struct inode *inode, struct file *file)
{
	int error = 0;
	/* update the statistics */
	if(capfs_collect_stats) capfs_vfs_stat.open++;
	PENTRY;
	
	lock_kernel();
	inode->i_mapping->host = inode;
	inode->i_mapping->a_ops = &capfs_file_aops;
	inode->i_mapping->backing_dev_info = &capfs_backing_dev_info;

	if (S_ISDIR(inode->i_mode))
	{
		error = dcache_dir_open(inode, file);
		unlock_kernel();
		return error;
	}
	/* we need to calculate file size if a) the user wants append mode or
	 * b) if O_LARGEFILE is not used (so that we can throw an error if
	 * the file is to large)
	 */
	if ((file->f_flags & O_APPEND) || !(file->f_flags & O_LARGEFILE))
	{
		/* force a revalidate */
		PDEBUG(D_FILE, "capfs_open: getting most up to date size\n");

		if ((error = capfs_inode_getattr(file->f_dentry)) < 0) {
			unlock_kernel();
			PEXIT;
			return error;
		}
	}

	/* make sure the file isn't too large */
	if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
	{
		unlock_kernel();
		PEXIT;
		return -EFBIG;
	}

	if (file->f_flags & O_APPEND)
	{
		/* set the file position to point to one byte past the last byte
		 * in the file
		 */
		file->f_pos = i_size_read(inode);
	}
	error = generic_file_open(inode, file);
	unlock_kernel();
	PEXIT;
	return error;
}
示例#3
0
文件: file.c 项目: cpady/ndas4linux
int 
xixfs_file_open(
		struct inode * inode, 
		struct file * filp
)
{

	struct super_block		*sb = NULL;
	PXIXFS_LINUX_VCB	pVCB = NULL;
	PXIXFS_LINUX_FCB	pFCB = NULL;
	int 			RC = 0;

	
	sb = inode->i_sb;
	XIXCORE_ASSERT(sb);
	pVCB = XIXFS_SB(sb);
	XIXFS_ASSERT_VCB(pVCB);
	
	pFCB = XIXFS_I(inode);
	XIXFS_ASSERT_FCB(pFCB);


	DebugTrace(DEBUG_LEVEL_ERROR, (DEBUG_TARGET_FCB|DEBUG_TARGET_VFSAPIT), 
		("ENTER xixfs_file_open (%s). MODE(0x%x). %d(%p)\n", filp->f_dentry->d_name.name, filp->f_flags, inode->i_ino, inode));	
		
	if( pFCB->XixcoreFcb.FCBType == FCB_TYPE_FILE) {

		if(XIXCORE_TEST_FLAGS(filp->f_flags, (O_WRONLY|O_RDWR| O_TRUNC|O_APPEND)) ){

			if(pFCB->XixcoreFcb.HasLock != INODE_FILE_LOCK_HAS) {

				RC = xixcore_LotLock(
							&pVCB->XixcoreVcb,
							pFCB->XixcoreFcb.LotNumber, 
							&pFCB->XixcoreFcb.HasLock, 
							1,
							1
							);

				/*
				if( RC < 0 ) {
					return -EINVAL;
				}
				*/
			}
		}
	}

	
	
	return  generic_file_open(inode, filp);
}
示例#4
0
/*
 * input :
 * @inode : vfs inode, the file to be open
 * @file : file descriptor
 * returns :
 * 0 if success else others
 */
static int nvmm_open_file(struct inode *inode, struct file *filp)
{
	int errval = 0;
//	pid_t pid = current->pid;
	errval = nvmm_establish_mapping(inode);
//	printk("the process pid is : %d\n", pid);
	if(errval){
		nvmm_error(inode->i_sb, __FUNCTION__, "can't establish mapping\n");
		return errval;
	}

	filp->f_flags |= O_DIRECT;
	return generic_file_open(inode, filp);
}
示例#5
0
文件: zpl_file.c 项目: shenyan1/zfs
static int
zpl_open(struct inode *ip, struct file *filp)
{
	cred_t *cr = CRED();
	int error;

	error = generic_file_open(ip, filp);
	if (error)
		return (error);

	crhold(cr);
	error = -zfs_open(ip, filp->f_mode, filp->f_flags, cr);
	crfree(cr);
	ASSERT3S(error, <=, 0);

	return (error);
}
示例#6
0
int
vnode_fop_open(
    INODE_T *ino_p,
    FILE_T *file_p
)
{
    int status = 0;
    VNODE_T *avp;
    VNODE_T *vp;
    CALL_DATA_T cd;

    /* No asserts on BKL; locking protocol is changing */

    ASSERT(MDKI_INOISOURS(ino_p));
    if (!MDKI_INOISMVFS(ino_p)) {
        MDKI_VFS_LOG(VFS_LOG_ERR,
                 "%s shouldn't be called on shadow?"
                 " (files swapped at open): vp %p fp %p\n",
                 __func__, ino_p, file_p);
        return -ENOSYS;
    }

    if ((status = generic_file_open(ino_p, file_p))) {
        return status;
    }

    avp = ITOV(ino_p);
    vp = avp;

    mdki_linux_init_call_data(&cd);
    status = VOP_OPEN(&vp, vnlayer_filep_to_flags(file_p), &cd, 
                     (file_ctx *)file_p);
    status = mdki_errno_unix_to_linux(status);
    mdki_linux_destroy_call_data(&cd);

    MDKI_TRACE(TRACE_OPEN, "%s opened vp=%p fp=%p pvt=%p pcnt=%ld\n",
              __func__, vp, file_p, REALFILE(file_p),
               REALFILE(file_p) ? (long)F_COUNT(REALFILE(file_p)) : 0);
    if (avp != vp) {
        printk("switcheroo on open? %p became %p\n", avp, vp); /* XXX */
        BUG();
    }

    return status;
}
示例#7
0
文件: zpl_file.c 项目: Alyseo/zfs
static int
zpl_open(struct inode *ip, struct file *filp)
{
	cred_t *cr = CRED();
	int error;
	fstrans_cookie_t cookie;

	error = generic_file_open(ip, filp);
	if (error)
		return (error);

	crhold(cr);
	cookie = spl_fstrans_mark();
	error = -zfs_open(ip, filp->f_mode, filp->f_flags, cr);
	spl_fstrans_unmark(cookie);
	crfree(cr);
	ASSERT3S(error, <=, 0);

	return (error);
}
示例#8
0
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;
}
示例#9
0
int fuse_open_common(struct inode *inode, struct file *file, int isdir)
{
	struct fuse_open_out outarg;
	struct fuse_file *ff;
	int err;

	/* VFS checks this, but only _after_ ->open() */
	if (file->f_flags & O_DIRECT)
		return -EINVAL;

	err = generic_file_open(inode, file);
	if (err)
		return err;

	/* If opening the root node, no lookup has been performed on
	   it, so the attributes must be refreshed */
	if (get_node_id(inode) == FUSE_ROOT_ID) {
		err = fuse_do_getattr(inode);
		if (err)
		 	return err;
	}

	ff = fuse_file_alloc();
	if (!ff)
		return -ENOMEM;

	err = fuse_send_open(inode, file, isdir, &outarg);
	if (err)
		fuse_file_free(ff);
	else {
		if (isdir)
			outarg.open_flags &= ~FOPEN_DIRECT_IO;
		fuse_finish_open(inode, file, ff, &outarg);
	}

	return err;
}
示例#10
0
文件: dfs_file.c 项目: aafoo/dirtyfs
 int
 dfs_file_open(struct inode *ino, struct file *filp)
 {
 	return generic_file_open(ino, filp);

 }
示例#11
0
int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
{
	struct inode *inode = file->f_mapping->host;
	struct f2fs_inode_info *fi = F2FS_I(inode);
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	nid_t ino = inode->i_ino;
	int ret = 0;
	bool need_cp = false;
	struct writeback_control wbc = {
		.sync_mode = WB_SYNC_ALL,
		.nr_to_write = LONG_MAX,
		.for_reclaim = 0,
	};

	if (unlikely(f2fs_readonly(inode->i_sb)))
		return 0;

	trace_f2fs_sync_file_enter(inode);

	/* if fdatasync is triggered, let's do in-place-update */
	if (get_dirty_pages(inode) <= SM_I(sbi)->min_fsync_blocks)
		set_inode_flag(fi, FI_NEED_IPU);
	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
	clear_inode_flag(fi, FI_NEED_IPU);

	if (ret) {
		trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
		return ret;
	}

	/* if the inode is dirty, let's recover all the time */
	if (!datasync && is_inode_flag_set(fi, FI_DIRTY_INODE)) {
		update_inode_page(inode);
		goto go_write;
	}

	/*
	 * if there is no written data, don't waste time to write recovery info.
	 */
	if (!is_inode_flag_set(fi, FI_APPEND_WRITE) &&
			!exist_written_data(sbi, ino, APPEND_INO)) {

		/* it may call write_inode just prior to fsync */
		if (need_inode_page_update(sbi, ino))
			goto go_write;

		if (is_inode_flag_set(fi, FI_UPDATE_WRITE) ||
				exist_written_data(sbi, ino, UPDATE_INO))
			goto flush_out;
		goto out;
	}
go_write:
	/* guarantee free sections for fsync */
	f2fs_balance_fs(sbi);

	/*
	 * Both of fdatasync() and fsync() are able to be recovered from
	 * sudden-power-off.
	 */
	down_read(&fi->i_sem);
	need_cp = need_do_checkpoint(inode);
	up_read(&fi->i_sem);

	if (need_cp) {
		/* all the dirty node pages should be flushed for POR */
		ret = f2fs_sync_fs(inode->i_sb, 1);

		/*
		 * We've secured consistency through sync_fs. Following pino
		 * will be used only for fsynced inodes after checkpoint.
		 */
		try_to_fix_pino(inode);
		clear_inode_flag(fi, FI_APPEND_WRITE);
		clear_inode_flag(fi, FI_UPDATE_WRITE);
		goto out;
	}
sync_nodes:
	sync_node_pages(sbi, ino, &wbc);

	/* if cp_error was enabled, we should avoid infinite loop */
	if (unlikely(f2fs_cp_error(sbi)))
		goto out;

	if (need_inode_block_update(sbi, ino)) {
		mark_inode_dirty_sync(inode);
		f2fs_write_inode(inode, NULL);
		goto sync_nodes;
	}

	ret = wait_on_node_pages_writeback(sbi, ino);
	if (ret)
		goto out;

	/* once recovery info is written, don't need to tack this */
	remove_dirty_inode(sbi, ino, APPEND_INO);
	clear_inode_flag(fi, FI_APPEND_WRITE);
flush_out:
	remove_dirty_inode(sbi, ino, UPDATE_INO);
	clear_inode_flag(fi, FI_UPDATE_WRITE);
	ret = f2fs_issue_flush(sbi);
out:
	trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
	f2fs_trace_ios(NULL, 1);
	return ret;
}

static pgoff_t __get_first_dirty_index(struct address_space *mapping,
						pgoff_t pgofs, int whence)
{
	struct pagevec pvec;
	int nr_pages;

	if (whence != SEEK_DATA)
		return 0;

	/* find first dirty page index */
	pagevec_init(&pvec, 0);
	nr_pages = pagevec_lookup_tag(&pvec, mapping, &pgofs,
					PAGECACHE_TAG_DIRTY, 1);
	pgofs = nr_pages ? pvec.pages[0]->index : LONG_MAX;
	pagevec_release(&pvec);
	return pgofs;
}

static bool __found_offset(block_t blkaddr, pgoff_t dirty, pgoff_t pgofs,
							int whence)
{
	switch (whence) {
	case SEEK_DATA:
		if ((blkaddr == NEW_ADDR && dirty == pgofs) ||
			(blkaddr != NEW_ADDR && blkaddr != NULL_ADDR))
			return true;
		break;
	case SEEK_HOLE:
		if (blkaddr == NULL_ADDR)
			return true;
		break;
	}
	return false;
}

static inline int unsigned_offsets(struct file *file)
{
	return file->f_mode & FMODE_UNSIGNED_OFFSET;
}

static loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize)
{
	if (offset < 0 && !unsigned_offsets(file))
		return -EINVAL;
	if (offset > maxsize)
		return -EINVAL;

	if (offset != file->f_pos) {
		file->f_pos = offset;
		file->f_version = 0;
	}
	return offset;
}

static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence)
{
	struct inode *inode = file->f_mapping->host;
	loff_t maxbytes = inode->i_sb->s_maxbytes;
	struct dnode_of_data dn;
	pgoff_t pgofs, end_offset, dirty;
	loff_t data_ofs = offset;
	loff_t isize;
	int err = 0;

	mutex_lock(&inode->i_mutex);

	isize = i_size_read(inode);
	if (offset >= isize)
		goto fail;

	/* handle inline data case */
	if (f2fs_has_inline_data(inode) || f2fs_has_inline_dentry(inode)) {
		if (whence == SEEK_HOLE)
			data_ofs = isize;
		goto found;
	}

	pgofs = (pgoff_t)(offset >> PAGE_CACHE_SHIFT);

	dirty = __get_first_dirty_index(inode->i_mapping, pgofs, whence);

	for (; data_ofs < isize; data_ofs = pgofs << PAGE_CACHE_SHIFT) {
		set_new_dnode(&dn, inode, NULL, NULL, 0);
		err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
		if (err && err != -ENOENT) {
			goto fail;
		} else if (err == -ENOENT) {
			/* direct node does not exists */
			if (whence == SEEK_DATA) {
				pgofs = PGOFS_OF_NEXT_DNODE(pgofs,
							F2FS_I(inode));
				continue;
			} else {
				goto found;
			}
		}

		end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));

		/* find data/hole in dnode block */
		for (; dn.ofs_in_node < end_offset;
				dn.ofs_in_node++, pgofs++,
				data_ofs = (loff_t)pgofs << PAGE_CACHE_SHIFT) {
			block_t blkaddr;
			blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);

			if (__found_offset(blkaddr, dirty, pgofs, whence)) {
				f2fs_put_dnode(&dn);
				goto found;
			}
		}
		f2fs_put_dnode(&dn);
	}

	if (whence == SEEK_DATA)
		goto fail;
found:
	if (whence == SEEK_HOLE && data_ofs > isize)
		data_ofs = isize;
	mutex_unlock(&inode->i_mutex);
	return vfs_setpos(file, data_ofs, maxbytes);
fail:
	mutex_unlock(&inode->i_mutex);
	return -ENXIO;
}

static loff_t f2fs_llseek(struct file *file, loff_t offset, int whence)
{
	struct inode *inode = file->f_mapping->host;
	loff_t maxbytes = inode->i_sb->s_maxbytes;

	switch (whence) {
	case SEEK_SET:
	case SEEK_CUR:
	case SEEK_END:
		return generic_file_llseek_size(file, offset, whence,
						maxbytes);
	case SEEK_DATA:
	case SEEK_HOLE:
		if (offset < 0)
			return -ENXIO;
		return f2fs_seek_block(file, offset, whence);
	}

	return -EINVAL;
}

static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct inode *inode = file_inode(file);

	if (f2fs_encrypted_inode(inode)) {
		int err = f2fs_get_encryption_info(inode);
		if (err)
			return 0;
	}

	/* we don't need to use inline_data strictly */
	if (f2fs_has_inline_data(inode)) {
		int err = f2fs_convert_inline_inode(inode);
		if (err)
			return err;
	}

	file_accessed(file);
	vma->vm_ops = &f2fs_file_vm_ops;
	return 0;
}

static int f2fs_file_open(struct inode *inode, struct file *filp)
{
	int ret = generic_file_open(inode, filp);

	if (!ret && f2fs_encrypted_inode(inode)) {
		ret = f2fs_get_encryption_info(inode);
		if (ret)
			ret = -EACCES;
	}
	return ret;
}
示例#12
0
文件: file.c 项目: 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;
}
示例#13
0
/*
 * @brief Called when an inode is about to be open.
 *
 * @param  inode    inode data structure to be opened
 * @param pfile       file data structure
 */
int yramfs_file_open(struct inode * inode, struct file * pfile)
{
    return generic_file_open(inode, pfile);
}