Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...

[karo-tx-linux.git] / fs / btrfs / file.c

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index a3492a3ad96b960fecec513d4023f7ee641fcf81..7351bdbca26f9eef18d024683067a80f5786c2c3 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -123,7 +123,10 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                    root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
 
        end_of_last_block = start_pos + num_bytes - 1;
-       btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block);
+       err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block);
+       if (err)
+               return err;
+
        for (i = 0; i < num_pages; i++) {
                struct page *p = pages[i];
                SetPageUptodate(p);
@@ -917,21 +920,35 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
        start_pos = pos;
 
        vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
+
+       /* do the reserve before the mutex lock in case we have to do some
+        * flushing.  We wouldn't deadlock, but this is more polite.
+        */
+       err = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+       if (err)
+               goto out_nolock;
+
+       mutex_lock(&inode->i_mutex);
+
        current->backing_dev_info = inode->i_mapping->backing_dev_info;
        err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
        if (err)
-               goto out_nolock;
+               goto out;
+
        if (count == 0)
-               goto out_nolock;
+               goto out;
 
        err = file_remove_suid(file);
        if (err)
-               goto out_nolock;
+               goto out;
+
        file_update_time(file);
 
        pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
 
-       mutex_lock(&inode->i_mutex);
+       /* generic_write_checks can change our pos */
+       start_pos = pos;
+
        BTRFS_I(inode)->sequence++;
        first_index = pos >> PAGE_CACHE_SHIFT;
        last_index = (pos + count) >> PAGE_CACHE_SHIFT;
@@ -1028,6 +1045,7 @@ out:
        mutex_unlock(&inode->i_mutex);
        if (ret)
                err = ret;
+       btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
 
 out_nolock:
        kfree(pages);