Btrfs: fallback on uncompressed io if compressed io fails

[cascardo/linux.git] / fs / btrfs / inode.c

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index bb7fd80..d3d7d46 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -538,7 +538,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
        struct btrfs_root *root = BTRFS_I(inode)->root;
        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
        struct extent_io_tree *io_tree;
-       int ret;
+       int ret = 0;
 
        if (list_empty(&async_cow->extents))
                return 0;
@@ -552,6 +552,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
 
                io_tree = &BTRFS_I(inode)->io_tree;
 
+retry:
                /* did the compression code fall back to uncompressed IO? */
                if (!async_extent->pages) {
                        int page_started = 0;
@@ -562,11 +563,11 @@ static noinline int submit_compressed_extents(struct inode *inode,
                                    async_extent->ram_size - 1, GFP_NOFS);
 
                        /* allocate blocks */
-                       cow_file_range(inode, async_cow->locked_page,
-                                      async_extent->start,
-                                      async_extent->start +
-                                      async_extent->ram_size - 1,
-                                      &page_started, &nr_written, 0);
+                       ret = cow_file_range(inode, async_cow->locked_page,
+                                            async_extent->start,
+                                            async_extent->start +
+                                            async_extent->ram_size - 1,
+                                            &page_started, &nr_written, 0);
 
                        /*
                         * if page_started, cow_file_range inserted an
@@ -574,7 +575,7 @@ static noinline int submit_compressed_extents(struct inode *inode,
                         * and IO for us.  Otherwise, we need to submit
                         * all those pages down to the drive.
                         */
-                       if (!page_started)
+                       if (!page_started && !ret)
                                extent_write_locked_range(io_tree,
                                                  inode, async_extent->start,
                                                  async_extent->start +
@@ -602,7 +603,21 @@ static noinline int submit_compressed_extents(struct inode *inode,
                                           async_extent->compressed_size,
                                           0, alloc_hint,
                                           (u64)-1, &ins, 1);
-               BUG_ON(ret);
+               if (ret) {
+                       int i;
+                       for (i = 0; i < async_extent->nr_pages; i++) {
+                               WARN_ON(async_extent->pages[i]->mapping);
+                               page_cache_release(async_extent->pages[i]);
+                       }
+                       kfree(async_extent->pages);
+                       async_extent->nr_pages = 0;
+                       async_extent->pages = NULL;
+                       unlock_extent(io_tree, async_extent->start,
+                                     async_extent->start +
+                                     async_extent->ram_size - 1, GFP_NOFS);
+                       goto retry;
+               }
+
                em = alloc_extent_map(GFP_NOFS);
                em->start = async_extent->start;
                em->len = async_extent->ram_size;