SYNC_FILE_RANGE_WAIT_AFTER)
/*
- * Do the filesystem syncing work. For simple filesystems sync_inodes_sb(sb, 0)
- * just dirties buffers with inodes so we have to submit IO for these buffers
- * via __sync_blockdev(). This also speeds up the wait == 1 case since in that
- * case write_inode() functions do sync_dirty_buffer() and thus effectively
- * write one block at a time.
+ * Do the filesystem syncing work. For simple filesystems
+ * writeback_inodes_sb(sb) just dirties buffers with inodes so we have to
+ * submit IO for these buffers via __sync_blockdev(). This also speeds up the
+ * wait == 1 case since in that case write_inode() functions do
+ * sync_dirty_buffer() and thus effectively write one block at a time.
*/
static int __sync_filesystem(struct super_block *sb, int wait)
{
- sync_quota_sb(sb, -1);
- sync_inodes_sb(sb, wait);
- lock_super(sb);
- if (sb->s_dirt && sb->s_op->write_super)
- sb->s_op->write_super(sb);
- unlock_super(sb);
+ /*
+ * This should be safe, as we require bdi backing to actually
+ * write out data in the first place
+ */
+ if (!sb->s_bdi)
+ return 0;
+
+ /* Avoid doing twice syncing and cache pruning for quota sync */
+ if (!wait) {
+ writeout_quota_sb(sb, -1);
+ writeback_inodes_sb(sb);
+ } else {
+ sync_quota_sb(sb, -1);
+ sync_inodes_sb(sb);
+ }
if (sb->s_op->sync_fs)
sb->s_op->sync_fs(sb, wait);
return __sync_blockdev(sb->s_bdev, wait);
{
int ret;
+ /*
+ * We need to be protected against the filesystem going from
+ * r/o to r/w or vice versa.
+ */
+ WARN_ON(!rwsem_is_locked(&sb->s_umount));
+
+ /*
+ * No point in syncing out anything if the filesystem is read-only.
+ */
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+
ret = __sync_filesystem(sb, 0);
if (ret < 0)
return ret;
mutex_lock(&mutex); /* Could be down_interruptible */
spin_lock(&sb_lock);
- list_for_each_entry(sb, &super_blocks, s_list) {
- if (sb->s_flags & MS_RDONLY)
- continue;
+ list_for_each_entry(sb, &super_blocks, s_list)
sb->s_need_sync = 1;
- }
restart:
list_for_each_entry(sb, &super_blocks, s_list) {
if (!sb->s_need_sync)
continue;
sb->s_need_sync = 0;
- if (sb->s_flags & MS_RDONLY)
- continue; /* hm. Was remounted r/o meanwhile */
sb->s_count++;
spin_unlock(&sb_lock);
+
down_read(&sb->s_umount);
- if (sb->s_root)
+ if (!(sb->s_flags & MS_RDONLY) && sb->s_root && sb->s_bdi)
__sync_filesystem(sb, wait);
up_read(&sb->s_umount);
+
/* restart only when sb is no longer on the list */
spin_lock(&sb_lock);
if (__put_super_and_need_restart(sb))
mutex_unlock(&mutex);
}
+/*
+ * sync everything. Start out by waking pdflush, because that writes back
+ * all queues in parallel.
+ */
SYSCALL_DEFINE0(sync)
{
+ wakeup_flusher_threads(0);
sync_filesystems(0);
sync_filesystems(1);
if (unlikely(laptop_mode))
/* sync the superblock to buffers */
sb = inode->i_sb;
- lock_super(sb);
if (sb->s_dirt && sb->s_op->write_super)
sb->s_op->write_super(sb);
- unlock_super(sb);
/* .. finally sync the buffers to disk */
err = sync_blockdev(sb->s_bdev);
ret = err;
return ret;
}
+EXPORT_SYMBOL(file_fsync);
/**
- * vfs_fsync - perform a fsync or fdatasync on a file
+ * vfs_fsync_range - helper to sync a range of data & metadata to disk
* @file: file to sync
* @dentry: dentry of @file
- * @data: only perform a fdatasync operation
+ * @start: offset in bytes of the beginning of data range to sync
+ * @end: offset in bytes of the end of data range (inclusive)
+ * @datasync: perform only datasync
*
- * Write back data and metadata for @file to disk. If @datasync is
- * set only metadata needed to access modified file data is written.
+ * Write back data in range @start..@end and metadata for @file to disk. If
+ * @datasync is set only metadata needed to access modified file data is
+ * written.
*
* In case this function is called from nfsd @file may be %NULL and
* only @dentry is set. This can only happen when the filesystem
* implements the export_operations API.
*/
-int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+int vfs_fsync_range(struct file *file, struct dentry *dentry, loff_t start,
+ loff_t end, int datasync)
{
const struct file_operations *fop;
struct address_space *mapping;
goto out;
}
- ret = filemap_fdatawrite(mapping);
+ ret = filemap_write_and_wait_range(mapping, start, end);
/*
* We need to protect against concurrent writers, which could cause
if (!ret)
ret = err;
mutex_unlock(&mapping->host->i_mutex);
- err = filemap_fdatawait(mapping);
- if (!ret)
- ret = err;
+
out:
return ret;
}
+EXPORT_SYMBOL(vfs_fsync_range);
+
+/**
+ * vfs_fsync - perform a fsync or fdatasync on a file
+ * @file: file to sync
+ * @dentry: dentry of @file
+ * @datasync: only perform a fdatasync operation
+ *
+ * Write back data and metadata for @file to disk. If @datasync is
+ * set only metadata needed to access modified file data is written.
+ *
+ * In case this function is called from nfsd @file may be %NULL and
+ * only @dentry is set. This can only happen when the filesystem
+ * implements the export_operations API.
+ */
+int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ return vfs_fsync_range(file, dentry, 0, LLONG_MAX, datasync);
+}
EXPORT_SYMBOL(vfs_fsync);
static int do_fsync(unsigned int fd, int datasync)
return do_fsync(fd, 1);
}
+/**
+ * generic_write_sync - perform syncing after a write if file / inode is sync
+ * @file: file to which the write happened
+ * @pos: offset where the write started
+ * @count: length of the write
+ *
+ * This is just a simple wrapper about our general syncing function.
+ */
+int generic_write_sync(struct file *file, loff_t pos, loff_t count)
+{
+ if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
+ return 0;
+ return vfs_fsync_range(file, file->f_path.dentry, pos,
+ pos + count - 1,
+ (file->f_flags & __O_SYNC) ? 0 : 1);
+}
+EXPORT_SYMBOL(generic_write_sync);
+
/*
* sys_sync_file_range() permits finely controlled syncing over a segment of
* a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
ret = 0;
if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
- ret = wait_on_page_writeback_range(mapping,
- offset >> PAGE_CACHE_SHIFT,
- endbyte >> PAGE_CACHE_SHIFT);
+ ret = filemap_fdatawait_range(mapping, offset, endbyte);
if (ret < 0)
goto out;
}
}
if (flags & SYNC_FILE_RANGE_WAIT_AFTER) {
- ret = wait_on_page_writeback_range(mapping,
- offset >> PAGE_CACHE_SHIFT,
- endbyte >> PAGE_CACHE_SHIFT);
+ ret = filemap_fdatawait_range(mapping, offset, endbyte);
}
out:
return ret;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff