From: Al Viro Date: Tue, 10 Dec 2024 00:15:58 +0000 (-0500) Subject: make sure that DNAME_INLINE_LEN is a multiple of word size X-Git-Tag: v6.14-rc1~38^2~19 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=61bc24ac974a4873e3040765e640f62fe99d6226;p=thirdparty%2Fkernel%2Flinux.git make sure that DNAME_INLINE_LEN is a multiple of word size ... calling the number of words DNAME_INLINE_WORDS. The next step will be to have a structure to hold inline name arrays (both in dentry and in name_snapshot) and use that to alias the existing arrays of unsigned char there. That will allow both full-structure copies and convenient word-by-word accesses. Reviewed-by: Jeff Layton Reviewed-by: Jan Kara Signed-off-by: Al Viro --- diff --git a/fs/dcache.c b/fs/dcache.c index b4d5e9e1e43da..ea0f0bea511be 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2748,9 +2748,7 @@ static void swap_names(struct dentry *dentry, struct dentry *target) /* * Both are internal. */ - unsigned int i; - BUILD_BUG_ON(!IS_ALIGNED(DNAME_INLINE_LEN, sizeof(long))); - for (i = 0; i < DNAME_INLINE_LEN / sizeof(long); i++) { + for (int i = 0; i < DNAME_INLINE_WORDS; i++) { swap(((long *) &dentry->d_iname)[i], ((long *) &target->d_iname)[i]); } diff --git a/include/linux/dcache.h b/include/linux/dcache.h index bff956f7b2b98..42dd89beaf4ed 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -68,15 +68,17 @@ extern const struct qstr dotdot_name; * large memory footprint increase). */ #ifdef CONFIG_64BIT -# define DNAME_INLINE_LEN 40 /* 192 bytes */ +# define DNAME_INLINE_WORDS 5 /* 192 bytes */ #else # ifdef CONFIG_SMP -# define DNAME_INLINE_LEN 36 /* 128 bytes */ +# define DNAME_INLINE_WORDS 9 /* 128 bytes */ # else -# define DNAME_INLINE_LEN 44 /* 128 bytes */ +# define DNAME_INLINE_WORDS 11 /* 128 bytes */ # endif #endif +#define DNAME_INLINE_LEN (DNAME_INLINE_WORDS*sizeof(unsigned long)) + #define d_lock d_lockref.lock struct dentry {