On Wed, May 11, 2022 at 03:31:39PM -0400, Gabriel Krisman Bertazi wrote:
> Keeping it as qstr avoids the unnecessary conversion in f2fs_match
>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
> ---
> fs/f2fs/dir.c | 52 ++++++++++++++++++++++++++++------------------
> fs/f2fs/f2fs.h | 3 ++-
> fs/f2fs/recovery.c | 5 +----
> 3 files changed, 35 insertions(+), 25 deletions(-)
>
> diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
> index 166f08623362..c2a02003c5b9 100644
> --- a/fs/f2fs/dir.c
> +++ b/fs/f2fs/dir.c
> @@ -81,28 +81,47 @@ int f2fs_init_casefolded_name(const struct inode *dir,
> {
> #if IS_ENABLED(CONFIG_UNICODE)
> struct super_block *sb = dir->i_sb;
> + unsigned char *buf;
> + int len;
>
> if (IS_CASEFOLDED(dir)) {
> - fname->cf_name.name = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
> + buf = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
> GFP_NOFS, false, F2FS_SB(sb));
> - if (!fname->cf_name.name)
> - return -ENOMEM;
> - fname->cf_name.len = utf8_casefold(sb->s_encoding,
> - fname->usr_fname,
> - fname->cf_name.name,
> - F2FS_NAME_LEN);
> - if ((int)fname->cf_name.len <= 0) {
> - kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
> + if (!buf) {
> fname->cf_name.name = NULL;
> + return -ENOMEM;
> + }
> +
> + len = utf8_casefold(sb->s_encoding, fname->usr_fname,
> + buf, F2FS_NAME_LEN);
> +
> + if (len <= 0) {
> + kmem_cache_free(f2fs_cf_name_slab, buf);
> + buf = NULL;
> if (sb_has_strict_encoding(sb))
> return -EINVAL;
> /* fall back to treating name as opaque byte sequence */
> }
> + fname->cf_name.name = buf;
> + fname->cf_name.len = (unsigned int) len;
> }
> #endif
There's some inconsistent behavior above; now sometimes fname->cf_name.name is
set to NULL on failure and sometime it's not. Also now fname->cf_name.len can
be set to a negative value.
Since struct f2fs_filename is always zero-initialized, how about only setting
the fname->cf_name fields if we actually have a valid value to assign? I.e.
buf = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
GFP_NOFS, false, F2FS_SB(sb));
if (!buf)
return -ENOMEM;
len = utf8_casefold(sb->s_encoding, fname->usr_fname,
buf, F2FS_NAME_LEN);
if (len <= 0) {
kmem_cache_free(f2fs_cf_name_slab, buf);
if (sb_has_strict_encoding(sb))
return -EINVAL;
/* fall back to treating name as opaque byte sequence */
return 0;
}
fname->cf_name.name = buf;
fname->cf_name.len = len;
> +void f2fs_free_casefolded_name(struct f2fs_filename *fname)
> +{
> +#if IS_ENABLED(CONFIG_UNICODE)
> + unsigned char *buf = (unsigned char *)fname->cf_name.name;
> +
> + if (buf) {
> + kmem_cache_free(f2fs_cf_name_slab, buf);
> + fname->cf_name.name = NULL;
> + }
> +
> +#endif
> +}
Kernel code usually uses static inline stubs for the !CONFIG_$FOO case in cases
like this, as that causes the function calls to be compiled away to nothing when
they're unneeded.
- Eric
