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-rw-r--r--fs/btrfs/ctree.h2
-rw-r--r--fs/btrfs/extent_map.c2
-rw-r--r--fs/btrfs/extent_map.h8
-rw-r--r--fs/btrfs/file.c97
-rw-r--r--fs/btrfs/inode.c4
-rw-r--r--fs/btrfs/ioctl.c256
-rw-r--r--fs/btrfs/lzo.c11
7 files changed, 296 insertions, 84 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 8992e0096163..947f04789389 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3291,7 +3291,7 @@ void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
int __init btrfs_auto_defrag_init(void);
void __cold btrfs_auto_defrag_exit(void);
int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
- struct btrfs_inode *inode);
+ struct btrfs_inode *inode, u32 extent_thresh);
int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info);
void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info);
int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync);
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 5a36add21305..c28ceddefae4 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -261,6 +261,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
em->mod_len = (em->mod_len + em->mod_start) - merge->mod_start;
em->mod_start = merge->mod_start;
em->generation = max(em->generation, merge->generation);
+ set_bit(EXTENT_FLAG_MERGED, &em->flags);
rb_erase_cached(&merge->rb_node, &tree->map);
RB_CLEAR_NODE(&merge->rb_node);
@@ -278,6 +279,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
RB_CLEAR_NODE(&merge->rb_node);
em->mod_len = (merge->mod_start + merge->mod_len) - em->mod_start;
em->generation = max(em->generation, merge->generation);
+ set_bit(EXTENT_FLAG_MERGED, &em->flags);
free_extent_map(merge);
}
}
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 8e217337dff9..d2fa32ffe304 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -25,6 +25,8 @@ enum {
EXTENT_FLAG_FILLING,
/* filesystem extent mapping type */
EXTENT_FLAG_FS_MAPPING,
+ /* This em is merged from two or more physically adjacent ems */
+ EXTENT_FLAG_MERGED,
};
struct extent_map {
@@ -40,6 +42,12 @@ struct extent_map {
u64 ram_bytes;
u64 block_start;
u64 block_len;
+
+ /*
+ * Generation of the extent map, for merged em it's the highest
+ * generation of all merged ems.
+ * For non-merged extents, it's from btrfs_file_extent_item::generation.
+ */
u64 generation;
unsigned long flags;
/* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 11204dbbe053..a0179cc62913 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -50,11 +50,14 @@ struct inode_defrag {
/* root objectid */
u64 root;
- /* last offset we were able to defrag */
- u64 last_offset;
-
- /* if we've wrapped around back to zero once already */
- int cycled;
+ /*
+ * The extent size threshold for autodefrag.
+ *
+ * This value is different for compressed/non-compressed extents,
+ * thus needs to be passed from higher layer.
+ * (aka, inode_should_defrag())
+ */
+ u32 extent_thresh;
};
static int __compare_inode_defrag(struct inode_defrag *defrag1,
@@ -107,8 +110,8 @@ static int __btrfs_add_inode_defrag(struct btrfs_inode *inode,
*/
if (defrag->transid < entry->transid)
entry->transid = defrag->transid;
- if (defrag->last_offset > entry->last_offset)
- entry->last_offset = defrag->last_offset;
+ entry->extent_thresh = min(defrag->extent_thresh,
+ entry->extent_thresh);
return -EEXIST;
}
}
@@ -134,7 +137,7 @@ static inline int __need_auto_defrag(struct btrfs_fs_info *fs_info)
* enabled
*/
int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
- struct btrfs_inode *inode)
+ struct btrfs_inode *inode, u32 extent_thresh)
{
struct btrfs_root *root = inode->root;
struct btrfs_fs_info *fs_info = root->fs_info;
@@ -160,6 +163,7 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
defrag->ino = btrfs_ino(inode);
defrag->transid = transid;
defrag->root = root->root_key.objectid;
+ defrag->extent_thresh = extent_thresh;
spin_lock(&fs_info->defrag_inodes_lock);
if (!test_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags)) {
@@ -179,34 +183,6 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
}
/*
- * Requeue the defrag object. If there is a defrag object that points to
- * the same inode in the tree, we will merge them together (by
- * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
- */
-static void btrfs_requeue_inode_defrag(struct btrfs_inode *inode,
- struct inode_defrag *defrag)
-{
- struct btrfs_fs_info *fs_info = inode->root->fs_info;
- int ret;
-
- if (!__need_auto_defrag(fs_info))
- goto out;
-
- /*
- * Here we don't check the IN_DEFRAG flag, because we need merge
- * them together.
- */
- spin_lock(&fs_info->defrag_inodes_lock);
- ret = __btrfs_add_inode_defrag(inode, defrag);
- spin_unlock(&fs_info->defrag_inodes_lock);
- if (ret)
- goto out;
- return;
-out:
- kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
-}
-
-/*
* pick the defragable inode that we want, if it doesn't exist, we will get
* the next one.
*/
@@ -278,8 +254,14 @@ static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
struct btrfs_root *inode_root;
struct inode *inode;
struct btrfs_ioctl_defrag_range_args range;
- int num_defrag;
- int ret;
+ int ret = 0;
+ u64 cur = 0;
+
+again:
+ if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
+ goto cleanup;
+ if (!__need_auto_defrag(fs_info))
+ goto cleanup;
/* get the inode */
inode_root = btrfs_get_fs_root(fs_info, defrag->root, true);
@@ -295,39 +277,30 @@ static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
goto cleanup;
}
+ if (cur >= i_size_read(inode)) {
+ iput(inode);
+ goto cleanup;
+ }
+
/* do a chunk of defrag */
clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
memset(&range, 0, sizeof(range));
range.len = (u64)-1;
- range.start = defrag->last_offset;
+ range.start = cur;
+ range.extent_thresh = defrag->extent_thresh;
sb_start_write(fs_info->sb);
- num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
+ ret = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
BTRFS_DEFRAG_BATCH);
sb_end_write(fs_info->sb);
- /*
- * if we filled the whole defrag batch, there
- * must be more work to do. Queue this defrag
- * again
- */
- if (num_defrag == BTRFS_DEFRAG_BATCH) {
- defrag->last_offset = range.start;
- btrfs_requeue_inode_defrag(BTRFS_I(inode), defrag);
- } else if (defrag->last_offset && !defrag->cycled) {
- /*
- * we didn't fill our defrag batch, but
- * we didn't start at zero. Make sure we loop
- * around to the start of the file.
- */
- defrag->last_offset = 0;
- defrag->cycled = 1;
- btrfs_requeue_inode_defrag(BTRFS_I(inode), defrag);
- } else {
- kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
- }
-
iput(inode);
- return 0;
+
+ if (ret < 0)
+ goto cleanup;
+
+ cur = max(cur + fs_info->sectorsize, range.start);
+ goto again;
+
cleanup:
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
return ret;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 3b2403b6127f..76e530f76e3c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -560,12 +560,12 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start,
}
static inline void inode_should_defrag(struct btrfs_inode *inode,
- u64 start, u64 end, u64 num_bytes, u64 small_write)
+ u64 start, u64 end, u64 num_bytes, u32 small_write)
{
/* If this is a small write inside eof, kick off a defrag */
if (num_bytes < small_write &&
(start > 0 || end + 1 < inode->disk_i_size))
- btrfs_add_inode_defrag(NULL, inode);
+ btrfs_add_inode_defrag(NULL, inode, small_write);
}
/*
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 927771d1853f..8d47ec5fc4f4 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1012,8 +1012,155 @@ out:
return ret;
}
+/*
+ * Defrag specific helper to get an extent map.
+ *
+ * Differences between this and btrfs_get_extent() are:
+ *
+ * - No extent_map will be added to inode->extent_tree
+ * To reduce memory usage in the long run.
+ *
+ * - Extra optimization to skip file extents older than @newer_than
+ * By using btrfs_search_forward() we can skip entire file ranges that
+ * have extents created in past transactions, because btrfs_search_forward()
+ * will not visit leaves and nodes with a generation smaller than given
+ * minimal generation threshold (@newer_than).
+ *
+ * Return valid em if we find a file extent matching the requirement.
+ * Return NULL if we can not find a file extent matching the requirement.
+ *
+ * Return ERR_PTR() for error.
+ */
+static struct extent_map *defrag_get_extent(struct btrfs_inode *inode,
+ u64 start, u64 newer_than)
+{
+ struct btrfs_root *root = inode->root;
+ struct btrfs_file_extent_item *fi;
+ struct btrfs_path path = { 0 };
+ struct extent_map *em;
+ struct btrfs_key key;
+ u64 ino = btrfs_ino(inode);
+ int ret;
+
+ em = alloc_extent_map();
+ if (!em) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ key.objectid = ino;
+ key.type = BTRFS_EXTENT_DATA_KEY;
+ key.offset = start;
+
+ if (newer_than) {
+ ret = btrfs_search_forward(root, &key, &path, newer_than);
+ if (ret < 0)
+ goto err;
+ /* Can't find anything newer */
+ if (ret > 0)
+ goto not_found;
+ } else {
+ ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+ if (ret < 0)
+ goto err;
+ }
+ if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
+ /*
+ * If btrfs_search_slot() makes path to point beyond nritems,
+ * we should not have an empty leaf, as this inode must at
+ * least have its INODE_ITEM.
+ */
+ ASSERT(btrfs_header_nritems(path.nodes[0]));
+ path.slots[0] = btrfs_header_nritems(path.nodes[0]) - 1;
+ }
+ btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+ /* Perfect match, no need to go one slot back */
+ if (key.objectid == ino && key.type == BTRFS_EXTENT_DATA_KEY &&
+ key.offset == start)
+ goto iterate;
+
+ /* We didn't find a perfect match, needs to go one slot back */
+ if (path.slots[0] > 0) {
+ btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+ if (key.objectid == ino && key.type == BTRFS_EXTENT_DATA_KEY)
+ path.slots[0]--;
+ }
+
+iterate:
+ /* Iterate through the path to find a file extent covering @start */
+ while (true) {
+ u64 extent_end;
+
+ if (path.slots[0] >= btrfs_header_nritems(path.nodes[0]))
+ goto next;
+
+ btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+
+ /*
+ * We may go one slot back to INODE_REF/XATTR item, then
+ * need to go forward until we reach an EXTENT_DATA.
+ * But we should still has the correct ino as key.objectid.
+ */
+ if (WARN_ON(key.objectid < ino) || key.type < BTRFS_EXTENT_DATA_KEY)
+ goto next;
+
+ /* It's beyond our target range, definitely not extent found */
+ if (key.objectid > ino || key.type > BTRFS_EXTENT_DATA_KEY)
+ goto not_found;
+
+ /*
+ * | |<- File extent ->|
+ * \- start
+ *
+ * This means there is a hole between start and key.offset.
+ */
+ if (key.offset > start) {
+ em->start = start;
+ em->orig_start = start;
+ em->block_start = EXTENT_MAP_HOLE;
+ em->len = key.offset - start;
+ break;
+ }
+
+ fi = btrfs_item_ptr(path.nodes[0], path.slots[0],
+ struct btrfs_file_extent_item);
+ extent_end = btrfs_file_extent_end(&path);
+
+ /*
+ * |<- file extent ->| |
+ * \- start
+ *
+ * We haven't reached start, search next slot.
+ */
+ if (extent_end <= start)
+ goto next;
+
+ /* Now this extent covers @start, convert it to em */
+ btrfs_extent_item_to_extent_map(inode, &path, fi, false, em);
+ break;
+next:
+ ret = btrfs_next_item(root, &path);
+ if (ret < 0)
+ goto err;
+ if (ret > 0)
+ goto not_found;
+ }
+ btrfs_release_path(&path);
+ return em;
+
+not_found:
+ btrfs_release_path(&path);
+ free_extent_map(em);
+ return NULL;
+
+err:
+ btrfs_release_path(&path);
+ free_extent_map(em);
+ return ERR_PTR(ret);
+}
+
static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
- bool locked)
+ u64 newer_than, bool locked)
{
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
@@ -1028,6 +1175,20 @@ static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
em = lookup_extent_mapping(em_tree, start, sectorsize);
read_unlock(&em_tree->lock);
+ /*
+ * We can get a merged extent, in that case, we need to re-search
+ * tree to get the original em for defrag.
+ *
+ * If @newer_than is 0 or em::generation < newer_than, we can trust
+ * this em, as either we don't care about the generation, or the
+ * merged extent map will be rejected anyway.
+ */
+ if (em && test_bit(EXTENT_FLAG_MERGED, &em->flags) &&
+ newer_than && em->generation >= newer_than) {
+ free_extent_map(em);
+ em = NULL;
+ }
+
if (!em) {
struct extent_state *cached = NULL;
u64 end = start + sectorsize - 1;
@@ -1035,7 +1196,7 @@ static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
/* get the big lock and read metadata off disk */
if (!locked)
lock_extent_bits(io_tree, start, end, &cached);
- em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, sectorsize);
+ em = defrag_get_extent(BTRFS_I(inode), start, newer_than);
if (!locked)
unlock_extent_cached(io_tree, start, end, &cached);
@@ -1046,23 +1207,42 @@ static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
return em;
}
+static u32 get_extent_max_capacity(const struct extent_map *em)
+{
+ if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+ return BTRFS_MAX_COMPRESSED;
+ return BTRFS_MAX_EXTENT_SIZE;
+}
+
static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em,
bool locked)
{
struct extent_map *next;
- bool ret = true;
+ bool ret = false;
/* this is the last extent */
if (em->start + em->len >= i_size_read(inode))
return false;
- next = defrag_lookup_extent(inode, em->start + em->len, locked);
+ /*
+ * We want to check if the next extent can be merged with the current
+ * one, which can be an extent created in a past generation, so we pass
+ * a minimum generation of 0 to defrag_lookup_extent().
+ */
+ next = defrag_lookup_extent(inode, em->start + em->len, 0, locked);
+ /* No more em or hole */
if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
- ret = false;
- else if ((em->block_start + em->block_len == next->block_start) &&
- (em->block_len > SZ_128K && next->block_len > SZ_128K))
- ret = false;
-
+ goto out;
+ if (test_bit(EXTENT_FLAG_PREALLOC, &next->flags))
+ goto out;
+ /*
+ * If the next extent is at its max capacity, defragging current extent
+ * makes no sense, as the total number of extents won't change.
+ */
+ if (next->len >= get_extent_max_capacity(em))
+ goto out;
+ ret = true;
+out:
free_extent_map(next);
return ret;
}
@@ -1186,8 +1366,10 @@ struct defrag_target_range {
static int defrag_collect_targets(struct btrfs_inode *inode,
u64 start, u64 len, u32 extent_thresh,
u64 newer_than, bool do_compress,
- bool locked, struct list_head *target_list)
+ bool locked, struct list_head *target_list,
+ u64 *last_scanned_ret)
{
+ bool last_is_target = false;
u64 cur = start;
int ret = 0;
@@ -1197,7 +1379,9 @@ static int defrag_collect_targets(struct btrfs_inode *inode,
bool next_mergeable = true;
u64 range_len;
- em = defrag_lookup_extent(&inode->vfs_inode, cur, locked);
+ last_is_target = false;
+ em = defrag_lookup_extent(&inode->vfs_inode, cur,
+ newer_than, locked);
if (!em)
break;
@@ -1254,6 +1438,13 @@ static int defrag_collect_targets(struct btrfs_inode *inode,
if (range_len >= extent_thresh)
goto next;
+ /*
+ * Skip extents already at its max capacity, this is mostly for
+ * compressed extents, which max cap is only 128K.
+ */
+ if (em->len >= get_extent_max_capacity(em))
+ goto next;
+
next_mergeable = defrag_check_next_extent(&inode->vfs_inode, em,
locked);
if (!next_mergeable) {
@@ -1272,6 +1463,7 @@ static int defrag_collect_targets(struct btrfs_inode *inode,
}
add:
+ last_is_target = true;
range_len = min(extent_map_end(em), start + len) - cur;
/*
* This one is a good target, check if it can be merged into
@@ -1315,6 +1507,17 @@ next:
kfree(entry);
}
}
+ if (!ret && last_scanned_ret) {
+ /*
+ * If the last extent is not a target, the caller can skip to
+ * the end of that extent.
+ * Otherwise, we can only go the end of the specified range.
+ */
+ if (!last_is_target)
+ *last_scanned_ret = max(cur, *last_scanned_ret);
+ else
+ *last_scanned_ret = max(start + len, *last_scanned_ret);
+ }
return ret;
}
@@ -1373,7 +1576,8 @@ static int defrag_one_locked_target(struct btrfs_inode *inode,
}
static int defrag_one_range(struct btrfs_inode *inode, u64 start, u32 len,
- u32 extent_thresh, u64 newer_than, bool do_compress)
+ u32 extent_thresh, u64 newer_than, bool do_compress,
+ u64 *last_scanned_ret)
{
struct extent_state *cached_state = NULL;
struct defrag_target_range *entry;
@@ -1419,7 +1623,7 @@ static int defrag_one_range(struct btrfs_inode *inode, u64 start, u32 len,
*/
ret = defrag_collect_targets(inode, start, len, extent_thresh,
newer_than, do_compress, true,
- &target_list);
+ &target_list, last_scanned_ret);
if (ret < 0)
goto unlock_extent;
@@ -1454,7 +1658,8 @@ static int defrag_one_cluster(struct btrfs_inode *inode,
u64 start, u32 len, u32 extent_thresh,
u64 newer_than, bool do_compress,
unsigned long *sectors_defragged,
- unsigned long max_sectors)
+ unsigned long max_sectors,
+ u64 *last_scanned_ret)
{
const u32 sectorsize = inode->root->fs_info->sectorsize;
struct defrag_target_range *entry;
@@ -1465,7 +1670,7 @@ static int defrag_one_cluster(struct btrfs_inode *inode,
BUILD_BUG_ON(!IS_ALIGNED(CLUSTER_SIZE, PAGE_SIZE));
ret = defrag_collect_targets(inode, start, len, extent_thresh,
newer_than, do_compress, false,
- &target_list);
+ &target_list, NULL);
if (ret < 0)
goto out;
@@ -1482,6 +1687,15 @@ static int defrag_one_cluster(struct btrfs_inode *inode,
range_len = min_t(u32, range_len,
(max_sectors - *sectors_defragged) * sectorsize);
+ /*
+ * If defrag_one_range() has updated last_scanned_ret,
+ * our range may already be invalid (e.g. hole punched).
+ * Skip if our range is before last_scanned_ret, as there is
+ * no need to defrag the range anymore.
+ */
+ if (entry->start + range_len <= *last_scanned_ret)
+ continue;
+
if (ra)
page_cache_sync_readahead(inode->vfs_inode.i_mapping,
ra, NULL, entry->start >> PAGE_SHIFT,
@@ -1494,7 +1708,8 @@ static int defrag_one_cluster(struct btrfs_inode *inode,
* accounting.
*/
ret = defrag_one_range(inode, entry->start, range_len,
- extent_thresh, newer_than, do_compress);
+ extent_thresh, newer_than, do_compress,
+ last_scanned_ret);
if (ret < 0)
break;
*sectors_defragged += range_len >>
@@ -1505,6 +1720,8 @@ out:
list_del_init(&entry->list);
kfree(entry);
}
+ if (ret >= 0)
+ *last_scanned_ret = max(*last_scanned_ret, start + len);
return ret;
}
@@ -1590,6 +1807,7 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
while (cur < last_byte) {
const unsigned long prev_sectors_defragged = sectors_defragged;
+ u64 last_scanned = cur;
u64 cluster_end;
/* The cluster size 256K should always be page aligned */
@@ -1619,8 +1837,8 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
BTRFS_I(inode)->defrag_compress = compress_type;
ret = defrag_one_cluster(BTRFS_I(inode), ra, cur,
cluster_end + 1 - cur, extent_thresh,
- newer_than, do_compress,
- &sectors_defragged, max_to_defrag);
+ newer_than, do_compress, &sectors_defragged,
+ max_to_defrag, &last_scanned);
if (sectors_defragged > prev_sectors_defragged)
balance_dirty_pages_ratelimited(inode->i_mapping);
@@ -1628,7 +1846,7 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
btrfs_inode_unlock(inode, 0);
if (ret < 0)
break;
- cur = cluster_end + 1;
+ cur = max(cluster_end + 1, last_scanned);
if (ret > 0) {
ret = 0;
break;
diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c
index 0fb90cbe7669..e6e28a9c7987 100644
--- a/fs/btrfs/lzo.c
+++ b/fs/btrfs/lzo.c
@@ -380,6 +380,17 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
kunmap(cur_page);
cur_in += LZO_LEN;
+ if (seg_len > lzo1x_worst_compress(PAGE_SIZE)) {
+ /*
+ * seg_len shouldn't be larger than we have allocated
+ * for workspace->cbuf
+ */
+ btrfs_err(fs_info, "unexpectedly large lzo segment len %u",
+ seg_len);
+ ret = -EIO;
+ goto out;
+ }
+
/* Copy the compressed segment payload into workspace */
copy_compressed_segment(cb, workspace->cbuf, seg_len, &cur_in);
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-11 21:34:02 +0000