diff options
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/ctree.h | 4 | ||||
-rw-r--r-- | fs/btrfs/disk-io.c | 4 | ||||
-rw-r--r-- | fs/btrfs/extent_io.c | 122 | ||||
-rw-r--r-- | fs/btrfs/tests/btrfs-tests.c | 22 |
4 files changed, 97 insertions, 55 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index e0d3cf2ec0dd..a240e8b83709 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -994,10 +994,10 @@ struct btrfs_fs_info { struct btrfs_delayed_root *delayed_root; - /* Extent buffer xarray */ + /* Extent buffer radix tree */ spinlock_t buffer_lock; /* Entries are eb->start / sectorsize */ - struct xarray extent_buffers; + struct radix_tree_root buffer_radix; /* next backup root to be overwritten */ int backup_root_index; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 88ba485b155b..f142ab43df36 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -486,7 +486,7 @@ static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info, uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur, fs_info->nodesize); - /* A dirty eb shouldn't disappear from extent_buffers */ + /* A dirty eb shouldn't disappear from buffer_radix */ if (WARN_ON(!eb)) return -EUCLEAN; @@ -3150,7 +3150,7 @@ static int __cold init_tree_roots(struct btrfs_fs_info *fs_info) void btrfs_init_fs_info(struct btrfs_fs_info *fs_info) { INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); - xa_init_flags(&fs_info->extent_buffers, GFP_ATOMIC); + INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC); INIT_LIST_HEAD(&fs_info->trans_list); INIT_LIST_HEAD(&fs_info->dead_roots); INIT_LIST_HEAD(&fs_info->delayed_iputs); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 9c250b8cd548..31729b1be5f3 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2966,7 +2966,7 @@ static void begin_page_read(struct btrfs_fs_info *fs_info, struct page *page) } /* - * Find extent buffer for a given bytenr. + * Find extent buffer for a givne bytenr. * * This is for end_bio_extent_readpage(), thus we can't do any unsafe locking * in endio context. @@ -2985,9 +2985,11 @@ static struct extent_buffer *find_extent_buffer_readpage( return (struct extent_buffer *)page->private; } - /* For subpage case, we need to lookup extent buffer xarray */ - eb = xa_load(&fs_info->extent_buffers, - bytenr >> fs_info->sectorsize_bits); + /* For subpage case, we need to lookup buffer radix tree */ + rcu_read_lock(); + eb = radix_tree_lookup(&fs_info->buffer_radix, + bytenr >> fs_info->sectorsize_bits); + rcu_read_unlock(); ASSERT(eb); return eb; } @@ -4434,8 +4436,8 @@ static struct extent_buffer *find_extent_buffer_nolock( struct extent_buffer *eb; rcu_read_lock(); - eb = xa_load(&fs_info->extent_buffers, - start >> fs_info->sectorsize_bits); + eb = radix_tree_lookup(&fs_info->buffer_radix, + start >> fs_info->sectorsize_bits); if (eb && atomic_inc_not_zero(&eb->refs)) { rcu_read_unlock(); return eb; @@ -6128,22 +6130,24 @@ struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, if (!eb) return ERR_PTR(-ENOMEM); eb->fs_info = fs_info; - - do { - ret = xa_insert(&fs_info->extent_buffers, - start >> fs_info->sectorsize_bits, - eb, GFP_NOFS); - if (ret == -ENOMEM) { - exists = ERR_PTR(ret); +again: + ret = radix_tree_preload(GFP_NOFS); + if (ret) { + exists = ERR_PTR(ret); + goto free_eb; + } + spin_lock(&fs_info->buffer_lock); + ret = radix_tree_insert(&fs_info->buffer_radix, + start >> fs_info->sectorsize_bits, eb); + spin_unlock(&fs_info->buffer_lock); + radix_tree_preload_end(); + if (ret == -EEXIST) { + exists = find_extent_buffer(fs_info, start); + if (exists) goto free_eb; - } - if (ret == -EBUSY) { - exists = find_extent_buffer(fs_info, start); - if (exists) - goto free_eb; - } - } while (ret); - + else + goto again; + } check_buffer_tree_ref(eb); set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags); @@ -6318,22 +6322,25 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, } if (uptodate) set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); - - do { - ret = xa_insert(&fs_info->extent_buffers, - start >> fs_info->sectorsize_bits, - eb, GFP_NOFS); - if (ret == -ENOMEM) { - exists = ERR_PTR(ret); +again: + ret = radix_tree_preload(GFP_NOFS); + if (ret) { + exists = ERR_PTR(ret); + goto free_eb; + } + + spin_lock(&fs_info->buffer_lock); + ret = radix_tree_insert(&fs_info->buffer_radix, + start >> fs_info->sectorsize_bits, eb); + spin_unlock(&fs_info->buffer_lock); + radix_tree_preload_end(); + if (ret == -EEXIST) { + exists = find_extent_buffer(fs_info, start); + if (exists) goto free_eb; - } - if (ret == -EBUSY) { - exists = find_extent_buffer(fs_info, start); - if (exists) - goto free_eb; - } - } while (ret); - + else + goto again; + } /* add one reference for the tree */ check_buffer_tree_ref(eb); set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags); @@ -6378,8 +6385,10 @@ static int release_extent_buffer(struct extent_buffer *eb) spin_unlock(&eb->refs_lock); - xa_erase(&fs_info->extent_buffers, - eb->start >> fs_info->sectorsize_bits); + spin_lock(&fs_info->buffer_lock); + radix_tree_delete(&fs_info->buffer_radix, + eb->start >> fs_info->sectorsize_bits); + spin_unlock(&fs_info->buffer_lock); } else { spin_unlock(&eb->refs_lock); } @@ -7324,25 +7333,42 @@ void memmove_extent_buffer(const struct extent_buffer *dst, } } +#define GANG_LOOKUP_SIZE 16 static struct extent_buffer *get_next_extent_buffer( struct btrfs_fs_info *fs_info, struct page *page, u64 bytenr) { - struct extent_buffer *eb; - unsigned long index; + struct extent_buffer *gang[GANG_LOOKUP_SIZE]; + struct extent_buffer *found = NULL; u64 page_start = page_offset(page); + u64 cur = page_start; ASSERT(in_range(bytenr, page_start, PAGE_SIZE)); lockdep_assert_held(&fs_info->buffer_lock); - xa_for_each_start(&fs_info->extent_buffers, index, eb, - page_start >> fs_info->sectorsize_bits) { - if (in_range(eb->start, page_start, PAGE_SIZE)) - return eb; - else if (eb->start >= page_start + PAGE_SIZE) - /* Already beyond page end */ - return NULL; + while (cur < page_start + PAGE_SIZE) { + int ret; + int i; + + ret = radix_tree_gang_lookup(&fs_info->buffer_radix, + (void **)gang, cur >> fs_info->sectorsize_bits, + min_t(unsigned int, GANG_LOOKUP_SIZE, + PAGE_SIZE / fs_info->nodesize)); + if (ret == 0) + goto out; + for (i = 0; i < ret; i++) { + /* Already beyond page end */ + if (gang[i]->start >= page_start + PAGE_SIZE) + goto out; + /* Found one */ + if (gang[i]->start >= bytenr) { + found = gang[i]; + goto out; + } + } + cur = gang[ret - 1]->start + gang[ret - 1]->len; } - return NULL; +out: + return found; } static int try_release_subpage_extent_buffer(struct page *page) diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c index c8c4efc9a3fb..d8e56edd6991 100644 --- a/fs/btrfs/tests/btrfs-tests.c +++ b/fs/btrfs/tests/btrfs-tests.c @@ -150,8 +150,8 @@ struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize) void btrfs_free_dummy_fs_info(struct btrfs_fs_info *fs_info) { - unsigned long index; - struct extent_buffer *eb; + struct radix_tree_iter iter; + void **slot; struct btrfs_device *dev, *tmp; if (!fs_info) @@ -163,9 +163,25 @@ void btrfs_free_dummy_fs_info(struct btrfs_fs_info *fs_info) test_mnt->mnt_sb->s_fs_info = NULL; - xa_for_each(&fs_info->extent_buffers, index, eb) { + spin_lock(&fs_info->buffer_lock); + radix_tree_for_each_slot(slot, &fs_info->buffer_radix, &iter, 0) { + struct extent_buffer *eb; + + eb = radix_tree_deref_slot_protected(slot, &fs_info->buffer_lock); + if (!eb) + continue; + /* Shouldn't happen but that kind of thinking creates CVE's */ + if (radix_tree_exception(eb)) { + if (radix_tree_deref_retry(eb)) + slot = radix_tree_iter_retry(&iter); + continue; + } + slot = radix_tree_iter_resume(slot, &iter); + spin_unlock(&fs_info->buffer_lock); free_extent_buffer_stale(eb); + spin_lock(&fs_info->buffer_lock); } + spin_unlock(&fs_info->buffer_lock); btrfs_mapping_tree_free(&fs_info->mapping_tree); list_for_each_entry_safe(dev, tmp, &fs_info->fs_devices->devices, |