From: Qu Wenruo <wqu@suse.com>
Date: Wed, 24 Oct 2018 20:24:01 +0800
Subject: btrfs: extent-tree: Detect bytes_may_use underflow earlier
Git-commit: 9f9b8e8d0ebe1af42ddd3c86e12569c53914a89d
Patch-mainline: v5.0-rc1
References: bsc#1165949
Although we have space_info::bytes_may_use underflow detection in
btrfs_free_reserved_data_space_noquota(), we have more callers who are
subtracting number from space_info::bytes_may_use.
So instead of doing underflow detection for every caller, introduce a
new wrapper update_bytes_may_use() to replace open coded bytes_may_use
modifiers.
This also introduce a macro to declare more wrappers, but currently
space_info::bytes_may_use is the mostly interesting one.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
fs/btrfs/extent-tree.c | 46 ++++++++++++++++++++++++++++++----------------
1 file changed, 30 insertions(+), 16 deletions(-)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -62,6 +62,23 @@ enum {
CHUNK_ALLOC_FORCE = 2,
};
+/*
+ * Declare a helper function to detect underflow of various space info members
+ */
+#define DECLARE_SPACE_INFO_UPDATE(name) \
+static inline void update_##name(struct btrfs_space_info *sinfo, \
+ s64 bytes) \
+{ \
+ if (bytes < 0 && sinfo->name < -bytes) { \
+ WARN_ON(1); \
+ sinfo->name = 0; \
+ return; \
+ } \
+ sinfo->name += bytes; \
+}
+
+DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
+
static int update_block_group(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 num_bytes, int alloc);
@@ -4382,7 +4399,7 @@ commit_trans:
data_sinfo->flags, bytes, 1);
return -ENOSPC;
}
- data_sinfo->bytes_may_use += bytes;
+ update_bytes_may_use(data_sinfo, bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
data_sinfo->flags, bytes, 1);
spin_unlock(&data_sinfo->lock);
@@ -4435,10 +4452,7 @@ void btrfs_free_reserved_data_space_noqu
data_sinfo = fs_info->data_sinfo;
spin_lock(&data_sinfo->lock);
- if (WARN_ON(data_sinfo->bytes_may_use < len))
- data_sinfo->bytes_may_use = 0;
- else
- data_sinfo->bytes_may_use -= len;
+ update_bytes_may_use(data_sinfo, -len);
trace_btrfs_space_reservation(fs_info, "space_info",
data_sinfo->flags, len, 0);
spin_unlock(&data_sinfo->lock);
@@ -5236,7 +5250,7 @@ static int wait_reserve_ticket(struct bt
list_del_init(&ticket->list);
if (ticket->bytes && ticket->bytes < orig_bytes) {
u64 num_bytes = orig_bytes - ticket->bytes;
- space_info->bytes_may_use -= num_bytes;
+ update_bytes_may_use(space_info, -num_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags, num_bytes, 0);
}
@@ -5282,12 +5296,12 @@ static int __reserve_metadata_bytes(stru
* If not things get more complicated.
*/
if (used + orig_bytes <= space_info->total_bytes) {
- space_info->bytes_may_use += orig_bytes;
+ update_bytes_may_use(space_info, orig_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags, orig_bytes, 1);
ret = 0;
} else if (can_overcommit(root, space_info, orig_bytes, flush)) {
- space_info->bytes_may_use += orig_bytes;
+ update_bytes_may_use(space_info, orig_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags, orig_bytes, 1);
ret = 0;
@@ -5349,7 +5363,7 @@ static int __reserve_metadata_bytes(stru
if (ticket.bytes) {
if (ticket.bytes < orig_bytes) {
u64 num_bytes = orig_bytes - ticket.bytes;
- space_info->bytes_may_use -= num_bytes;
+ update_bytes_may_use(space_info, -num_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags,
num_bytes, 0);
@@ -5530,7 +5544,7 @@ again:
flush = BTRFS_RESERVE_FLUSH_ALL;
goto again;
}
- space_info->bytes_may_use -= num_bytes;
+ update_bytes_may_use(space_info, -num_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags, num_bytes, 0);
spin_unlock(&space_info->lock);
@@ -5558,7 +5572,7 @@ again:
ticket->bytes, 1);
list_del_init(&ticket->list);
num_bytes -= ticket->bytes;
- space_info->bytes_may_use += ticket->bytes;
+ update_bytes_may_use(space_info, ticket->bytes);
ticket->bytes = 0;
space_info->tickets_id++;
wake_up(&ticket->wait);
@@ -5566,7 +5580,7 @@ again:
trace_btrfs_space_reservation(fs_info, "space_info",
space_info->flags,
num_bytes, 1);
- space_info->bytes_may_use += num_bytes;
+ update_bytes_may_use(space_info, num_bytes);
ticket->bytes -= num_bytes;
num_bytes = 0;
}
@@ -5880,14 +5894,14 @@ static void update_global_block_rsv(stru
num_bytes = min(num_bytes,
block_rsv->size - block_rsv->reserved);
block_rsv->reserved += num_bytes;
- sinfo->bytes_may_use += num_bytes;
+ update_bytes_may_use(sinfo, num_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
sinfo->flags, num_bytes,
1);
}
} else if (block_rsv->reserved > block_rsv->size) {
num_bytes = block_rsv->reserved - block_rsv->size;
- sinfo->bytes_may_use -= num_bytes;
+ update_bytes_may_use(sinfo, -num_bytes);
trace_btrfs_space_reservation(fs_info, "space_info",
sinfo->flags, num_bytes, 0);
block_rsv->reserved = block_rsv->size;
@@ -6601,7 +6615,7 @@ static int btrfs_add_reserved_bytes(stru
trace_btrfs_space_reservation(cache->fs_info,
"space_info", space_info->flags,
ram_bytes, 0);
- space_info->bytes_may_use -= ram_bytes;
+ update_bytes_may_use(space_info, -ram_bytes);
if (delalloc)
cache->delalloc_bytes += num_bytes;
}
@@ -6778,7 +6792,7 @@ static int unpin_extent_range(struct btr
to_add = min(len, global_rsv->size -
global_rsv->reserved);
global_rsv->reserved += to_add;
- space_info->bytes_may_use += to_add;
+ update_bytes_may_use(space_info, to_add);
if (global_rsv->reserved >= global_rsv->size)
global_rsv->full = 1;
trace_btrfs_space_reservation(fs_info,