diff options
Diffstat (limited to 'fs/bio.c')
| -rw-r--r-- | fs/bio.c | 40 |
1 files changed, 26 insertions, 14 deletions
@@ -325,8 +325,16 @@ static void bio_fs_destructor(struct bio *bio) * @gfp_mask: allocation mask to use * @nr_iovecs: number of iovecs * - * Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask - * contains __GFP_WAIT, the allocation is guaranteed to succeed. + * bio_alloc will allocate a bio and associated bio_vec array that can hold + * at least @nr_iovecs entries. Allocations will be done from the + * fs_bio_set. Also see @bio_alloc_bioset and @bio_kmalloc. + * + * If %__GFP_WAIT is set, then bio_alloc will always be able to allocate + * a bio. This is due to the mempool guarantees. To make this work, callers + * must never allocate more than 1 bio at a time from this pool. Callers + * that need to allocate more than 1 bio must always submit the previously + * allocated bio for IO before attempting to allocate a new one. Failure to + * do so can cause livelocks under memory pressure. * * RETURNS: * Pointer to new bio on success, NULL on failure. @@ -350,21 +358,13 @@ static void bio_kmalloc_destructor(struct bio *bio) } /** - * bio_alloc - allocate a bio for I/O + * bio_kmalloc - allocate a bio for I/O using kmalloc() * @gfp_mask: the GFP_ mask given to the slab allocator * @nr_iovecs: number of iovecs to pre-allocate * * Description: - * bio_alloc will allocate a bio and associated bio_vec array that can hold - * at least @nr_iovecs entries. Allocations will be done from the - * fs_bio_set. Also see @bio_alloc_bioset. - * - * If %__GFP_WAIT is set, then bio_alloc will always be able to allocate - * a bio. This is due to the mempool guarantees. To make this work, callers - * must never allocate more than 1 bio at a time from this pool. Callers - * that need to allocate more than 1 bio must always submit the previously - * allocated bio for IO before attempting to allocate a new one. Failure to - * do so can cause livelocks under memory pressure. + * Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask contains + * %__GFP_WAIT, the allocation is guaranteed to succeed. * **/ struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs) @@ -407,7 +407,7 @@ EXPORT_SYMBOL(zero_fill_bio); * * Description: * Put a reference to a &struct bio, either one you have gotten with - * bio_alloc or bio_get. The last put of a bio will free it. + * bio_alloc, bio_get or bio_clone. The last put of a bio will free it. **/ void bio_put(struct bio *bio) { @@ -1393,6 +1393,18 @@ void bio_check_pages_dirty(struct bio *bio) } } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +void bio_flush_dcache_pages(struct bio *bi) +{ + int i; + struct bio_vec *bvec; + + bio_for_each_segment(bvec, bi, i) + flush_dcache_page(bvec->bv_page); +} +EXPORT_SYMBOL(bio_flush_dcache_pages); +#endif + /** * bio_endio - end I/O on a bio * @bio: bio |