diff options
| author | Przemek Kitszel <przemyslaw.kitszel@intel.com> | 2025-03-20 11:22:19 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-05-11 17:48:19 -0700 |
| commit | 4c97a17a252bf8396f7bd65efced00bf401a8c25 (patch) | |
| tree | bfdfe7beb540ce8a243ac2e3d7d5a61f924c1f27 /include/linux/xarray.h | |
| parent | dbb9c166a08c7a237c79b969a19ee02baa847af1 (diff) | |
xarray: make xa_alloc_cyclic() return 0 on all success cases
Change xa_alloc_cyclic() to return 0 even on wrap-around. Do the same for
xa_alloc_cyclic_irq() and xa_alloc_cyclic_bh().
This will prevent any future bug of treating return of 1 as an error:
int ret = xa_alloc_cyclic(...)
if (ret) // currently mishandles ret==1
goto failure;
If there will be someone interested in when wrap-around occurs, there is
still __xa_alloc_cyclic() that behaves as before. For now there is no
such user.
Link: https://lkml.kernel.org/r/20250320102219.8101-1-przemyslaw.kitszel@intel.com
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Link: https://lore.kernel.org/netdev/Z9gUd-5t8b5NX2wE@casper.infradead.org
Cc: Andriy Shevchenko <andriy.shevchenko@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Cc: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/xarray.h')
| -rw-r--r-- | include/linux/xarray.h | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/include/linux/xarray.h b/include/linux/xarray.h index 78eede109b1a..be850174e802 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -965,10 +965,12 @@ static inline int __must_check xa_alloc_irq(struct xarray *xa, u32 *id, * Must only be operated on an xarray initialized with flag XA_FLAGS_ALLOC set * in xa_init_flags(). * + * Note that callers interested in whether wrapping has occurred should + * use __xa_alloc_cyclic() instead. + * * Context: Any context. Takes and releases the xa_lock. May sleep if * the @gfp flags permit. - * Return: 0 if the allocation succeeded without wrapping. 1 if the - * allocation succeeded after wrapping, -ENOMEM if memory could not be + * Return: 0 if the allocation succeeded, -ENOMEM if memory could not be * allocated or -EBUSY if there are no free entries in @limit. */ static inline int xa_alloc_cyclic(struct xarray *xa, u32 *id, void *entry, @@ -981,7 +983,7 @@ static inline int xa_alloc_cyclic(struct xarray *xa, u32 *id, void *entry, err = __xa_alloc_cyclic(xa, id, entry, limit, next, gfp); xa_unlock(xa); - return err; + return err < 0 ? err : 0; } /** @@ -1002,10 +1004,12 @@ static inline int xa_alloc_cyclic(struct xarray *xa, u32 *id, void *entry, * Must only be operated on an xarray initialized with flag XA_FLAGS_ALLOC set * in xa_init_flags(). * + * Note that callers interested in whether wrapping has occurred should + * use __xa_alloc_cyclic() instead. + * * Context: Any context. Takes and releases the xa_lock while * disabling softirqs. May sleep if the @gfp flags permit. - * Return: 0 if the allocation succeeded without wrapping. 1 if the - * allocation succeeded after wrapping, -ENOMEM if memory could not be + * Return: 0 if the allocation succeeded, -ENOMEM if memory could not be * allocated or -EBUSY if there are no free entries in @limit. */ static inline int xa_alloc_cyclic_bh(struct xarray *xa, u32 *id, void *entry, @@ -1018,7 +1022,7 @@ static inline int xa_alloc_cyclic_bh(struct xarray *xa, u32 *id, void *entry, err = __xa_alloc_cyclic(xa, id, entry, limit, next, gfp); xa_unlock_bh(xa); - return err; + return err < 0 ? err : 0; } /** @@ -1039,10 +1043,12 @@ static inline int xa_alloc_cyclic_bh(struct xarray *xa, u32 *id, void *entry, * Must only be operated on an xarray initialized with flag XA_FLAGS_ALLOC set * in xa_init_flags(). * + * Note that callers interested in whether wrapping has occurred should + * use __xa_alloc_cyclic() instead. + * * Context: Process context. Takes and releases the xa_lock while * disabling interrupts. May sleep if the @gfp flags permit. - * Return: 0 if the allocation succeeded without wrapping. 1 if the - * allocation succeeded after wrapping, -ENOMEM if memory could not be + * Return: 0 if the allocation succeeded, -ENOMEM if memory could not be * allocated or -EBUSY if there are no free entries in @limit. */ static inline int xa_alloc_cyclic_irq(struct xarray *xa, u32 *id, void *entry, @@ -1055,7 +1061,7 @@ static inline int xa_alloc_cyclic_irq(struct xarray *xa, u32 *id, void *entry, err = __xa_alloc_cyclic(xa, id, entry, limit, next, gfp); xa_unlock_irq(xa); - return err; + return err < 0 ? err : 0; } /** |