[PATCH 1/1] btrfs: Simplify parsing max_inline mount option

[Vladimir Panteleev <git@xxxxxxxxxxxxxxxxxx>]

- Avoid an allocation;
- Properly handle non-numerical argument and garbage after numerical
  argument.

Signed-off-by: Vladimir Panteleev <git@xxxxxxxxxxxxxxxxxx>
---
 fs/btrfs/super.c | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index f56617dfb3cf..6fe8ef6667f3 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -426,7 +426,7 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
 			unsigned long new_flags)
 {
 	substring_t args[MAX_OPT_ARGS];
-	char *p, *num;
+	char *p, *retptr;
 	u64 cache_gen;
 	int intarg;
 	int ret = 0;
@@ -630,22 +630,16 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
 			info->thread_pool_size = intarg;
 			break;
 		case Opt_max_inline:
-			num = match_strdup(&args[0]);
-			if (num) {
-				info->max_inline = memparse(num, NULL);
-				kfree(num);
-
-				if (info->max_inline) {
-					info->max_inline = min_t(u64,
-						info->max_inline,
-						info->sectorsize);
-				}
-				btrfs_info(info, "max_inline at %llu",
-					   info->max_inline);
-			} else {
-				ret = -ENOMEM;
+			info->max_inline = memparse(args[0].from, &retptr);
+			if (retptr != args[0].to || info->max_inline == 0) {
+				ret = -EINVAL;
 				goto out;
 			}
+			info->max_inline = min_t(u64,
+				info->max_inline,
+				info->sectorsize);
+			btrfs_info(info, "max_inline at %llu",
+				   info->max_inline);
 			break;
 		case Opt_alloc_start:
 			btrfs_info(info,
-- 
2.22.0