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Btrfs: fix page leak when allocing extent buffers

If we happen to alloc a extent buffer and then alloc a page and notice that page is already attached to an extent buffer, we will only unlock it and free our existing eb. Any pages currently attached to that eb will be properly freed, but we don't do the page_cache_release() on the page where we noticed the other extent buffer which can cause us to leak pages and I hope cause the weird issues we've been seeing in this area. Thanks,

Josef Bacik committed 14 years ago

Commit 17de39a1 parent e5846fc1 file · +2 −2Browse files

Unified · Split

fs/btrfs/extent_io.c+2−2
@@ -4120,6 +4120,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, · 4119 unmodified lines
4120 if (atomic_inc_not_zero(&exists->refs)) {4120 if (atomic_inc_not_zero(&exists->refs)) {
4121 spin_unlock(&mapping->private_lock);4121 spin_unlock(&mapping->private_lock);
4122 unlock_page(p);4122 unlock_page(p);
4123 page_cache_release(p);
4123 mark_extent_buffer_accessed(exists);4124 mark_extent_buffer_accessed(exists);
4124 goto free_eb;4125 goto free_eb;
4125 }4126 }
@@ -4199,8 +4200,7 @@ free_eb: · 73 unmodified lines
4199 unlock_page(eb->pages[i]);4200 unlock_page(eb->pages[i]);
4200 }4201 }
4201 4202
4202 if (!atomic_dec_and_test(&eb->refs))4203 WARN_ON(!atomic_dec_and_test(&eb->refs));
4203 return exists;
4204 btrfs_release_extent_buffer(eb);4204 btrfs_release_extent_buffer(eb);
4205 return exists;4205 return exists;
4206}4206}