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| author | Christian Brauner <brauner@kernel.org> | 2024-06-27 16:11:39 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-06-28 10:36:45 +0200 |
| commit | c6269149cbf7053272d918101981869438ff7c1e (patch) | |
| tree | 56268222b9012639dff71b6a54f5e756a82ed3cc /include/linux/cleanup.h | |
| parent | ff2c570ef7eaa9ded58e7a02dd7a68874a897508 (diff) | |
| download | linux-next-c6269149cbf7053272d918101981869438ff7c1e.tar.gz linux-next-c6269149cbf7053272d918101981869438ff7c1e.zip | |
file: add take_fd() cleanup helper
Add a helper that returns the file descriptor and ensures that the old
variable contains a negative value. This makes it easy to rely on
CLASS(get_unused_fd).
Link: https://lore.kernel.org/r/20240627-work-pidfs-v1-1-7e9ab6cc3bb1@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/linux/cleanup.h')
| -rw-r--r-- | include/linux/cleanup.h | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h index c2d09bc4f976..80c4181e194a 100644 --- a/include/linux/cleanup.h +++ b/include/linux/cleanup.h @@ -63,17 +63,20 @@ #define __free(_name) __cleanup(__free_##_name) -#define __get_and_null_ptr(p) \ - ({ __auto_type __ptr = &(p); \ - __auto_type __val = *__ptr; \ - *__ptr = NULL; __val; }) +#define __get_and_null(p, nullvalue) \ + ({ \ + __auto_type __ptr = &(p); \ + __auto_type __val = *__ptr; \ + *__ptr = nullvalue; \ + __val; \ + }) static inline __must_check const volatile void * __must_check_fn(const volatile void *val) { return val; } #define no_free_ptr(p) \ - ((typeof(p)) __must_check_fn(__get_and_null_ptr(p))) + ((typeof(p)) __must_check_fn(__get_and_null(p, NULL))) #define return_ptr(p) return no_free_ptr(p) |