diff options
| -rw-r--r-- | mm/shmem.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index ad533b2f0721..aeb1fd19ea3f 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2137,12 +2137,32 @@ unlock: return error; } +/** + * shmem_get_folio - find, and lock a shmem folio. + * @inode: inode to search + * @index: the page index. + * @foliop: pointer to the folio if found + * @sgp: SGP_* flags to control behavior + * + * Looks up the page cache entry at @inode & @index. If a folio is + * present, it is returned locked with an increased refcount. + * + * When no folio is found, the behavior depends on @sgp: + * - for SGP_READ, *foliop is %NULL and 0 is returned + * - for SGP_NOALLOC, *foliop is %NULL and -ENOENT is returned + * - for all other flags a new folio is allocated, inserted into the + * page cache and returned locked in @foliop. + * + * Context: May sleep. + * Return: 0 if successful, else a negative error code. + */ int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop, enum sgp_type sgp) { return shmem_get_folio_gfp(inode, index, foliop, sgp, mapping_gfp_mask(inode->i_mapping), NULL, NULL); } +EXPORT_SYMBOL_GPL(shmem_get_folio); /* * This is like autoremove_wake_function, but it removes the wait queue |