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author | Hao Sun <sunhao.th@gmail.com> | 2022-12-21 15:42:45 +0100 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-01-19 02:12:47 +0100 |
commit | 0b7b8704ddcee372099a2bc6781db6ab273a85d5 (patch) | |
tree | c1c8de77ddf39a5db49b97611c4b7f019aa81990 /mm/util.c | |
parent | mm/swap: convert deactivate_page() to folio_deactivate() (diff) | |
download | linux-0b7b8704ddcee372099a2bc6781db6ab273a85d5.tar.xz linux-0b7b8704ddcee372099a2bc6781db6ab273a85d5.zip |
mm: new primitive kvmemdup()
Similar to kmemdup(), but support large amount of bytes with kvmalloc()
and does *not* guarantee that the result will be physically contiguous.
Use only in cases where kvmalloc() is needed and free it with kvfree().
Also adapt policy_unpack.c in case someone bisect into this.
Link: https://lkml.kernel.org/r/20221221144245.27164-1-sunhao.th@gmail.com
Signed-off-by: Hao Sun <sunhao.th@gmail.com>
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Nick Terrell <terrelln@fb.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/util.c')
-rw-r--r-- | mm/util.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/mm/util.c b/mm/util.c index b56c92fb910f..cec9327b27b4 100644 --- a/mm/util.c +++ b/mm/util.c @@ -120,7 +120,8 @@ EXPORT_SYMBOL(kstrndup); * @len: memory region length * @gfp: GFP mask to use * - * Return: newly allocated copy of @src or %NULL in case of error + * Return: newly allocated copy of @src or %NULL in case of error, + * result is physically contiguous. Use kfree() to free. */ void *kmemdup(const void *src, size_t len, gfp_t gfp) { @@ -134,6 +135,27 @@ void *kmemdup(const void *src, size_t len, gfp_t gfp) EXPORT_SYMBOL(kmemdup); /** + * kvmemdup - duplicate region of memory + * + * @src: memory region to duplicate + * @len: memory region length + * @gfp: GFP mask to use + * + * Return: newly allocated copy of @src or %NULL in case of error, + * result may be not physically contiguous. Use kvfree() to free. + */ +void *kvmemdup(const void *src, size_t len, gfp_t gfp) +{ + void *p; + + p = kvmalloc(len, gfp); + if (p) + memcpy(p, src, len); + return p; +} +EXPORT_SYMBOL(kvmemdup); + +/** * kmemdup_nul - Create a NUL-terminated string from unterminated data * @s: The data to stringify * @len: The size of the data |