From 4f60152910c6bbc1c7975409f852af7ef11c7007 Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Tue, 27 Sep 2016 17:30:02 -0400 Subject: [PATCH] ABD kmap to kmap_atomic Convert usage of kmap to kmap_atomic while correctly saving off irq state. --- module/zfs/abd.c | 84 ++++++++++++++++++++++++++++-------------------- 1 file changed, 49 insertions(+), 35 deletions(-) diff --git a/module/zfs/abd.c b/module/zfs/abd.c index 08bb0c52e..6436d3b1f 100644 --- a/module/zfs/abd.c +++ b/module/zfs/abd.c @@ -119,6 +119,9 @@ #include #include #include +#ifdef _KERNEL +#include +#endif #ifndef KMC_NOTOUCH #define KMC_NOTOUCH 0 @@ -187,22 +190,6 @@ abd_free_chunk(struct page *c) __free_pages(c, 0); } -static void * -abd_map_chunk(struct page *c) -{ - /* - * Use of segkpm means we don't care if this is mapped S_READ or S_WRITE - * but S_WRITE is conceptually more accurate. - */ - return (kmap(c)); -} - -static void -abd_unmap_chunk(struct page *c) -{ - kunmap(c); -} - void abd_init(void) { @@ -230,11 +217,10 @@ struct page; #define abd_alloc_chunk() \ ((struct page *) umem_alloc_aligned(PAGESIZE, 64, KM_SLEEP)) #define abd_free_chunk(chunk) umem_free(chunk, PAGESIZE) -#define abd_map_chunk(chunk) ((void *)chunk) -static void -abd_unmap_chunk(struct page *c) -{ -} +#define zfs_kmap_atomic(chunk, km) ((void *)chunk) +#define zfs_kunmap_atomic(addr, km) do { (void)(addr); } while (0) +#define local_irq_save(flags) do { (void)(flags); } while (0) +#define local_irq_restore(flags) do { (void)(flags); } while (0) void abd_init(void) @@ -697,11 +683,28 @@ abd_release_ownership_of_buf(abd_t *abd) ABDSTAT_INCR(abdstat_linear_data_size, -(int)abd->abd_size); } +#ifndef HAVE_1ARG_KMAP_ATOMIC +#define NR_KM_TYPE (6) +#ifdef _KERNEL +int km_table[NR_KM_TYPE] = { + KM_USER0, + KM_USER1, + KM_BIO_SRC_IRQ, + KM_BIO_DST_IRQ, + KM_PTE0, + KM_PTE1, +}; +#endif +#endif + struct abd_iter { abd_t *iter_abd; /* ABD being iterated through */ size_t iter_pos; /* position (relative to abd_offset) */ void *iter_mapaddr; /* addr corresponding to iter_pos */ size_t iter_mapsize; /* length of data valid at mapaddr */ +#ifndef HAVE_1ARG_KMAP_ATOMIC + int iter_km; /* KM_* for kmap_atomic */ +#endif }; static inline size_t @@ -724,13 +727,17 @@ abd_iter_scatter_chunk_index(struct abd_iter *aiter) * Initialize the abd_iter. */ static void -abd_iter_init(struct abd_iter *aiter, abd_t *abd) +abd_iter_init(struct abd_iter *aiter, abd_t *abd, int km_type) { abd_verify(abd); aiter->iter_abd = abd; aiter->iter_pos = 0; aiter->iter_mapaddr = NULL; aiter->iter_mapsize = 0; +#ifndef HAVE_1ARG_KMAP_ATOMIC + ASSERT3U(km_type, <, NR_KM_TYPE); + aiter->iter_km = km_type; +#endif } /* @@ -779,8 +786,9 @@ abd_iter_map(struct abd_iter *aiter) aiter->iter_mapsize = MIN(PAGESIZE - offset, aiter->iter_abd->abd_size - aiter->iter_pos); - paddr = abd_map_chunk( - aiter->iter_abd->abd_u.abd_scatter.abd_chunks[index]); + paddr = zfs_kmap_atomic( + aiter->iter_abd->abd_u.abd_scatter.abd_chunks[index], + km_table[aiter->iter_km]); } aiter->iter_mapaddr = (char *)paddr + offset; @@ -799,9 +807,9 @@ abd_iter_unmap(struct abd_iter *aiter) if (!abd_is_linear(aiter->iter_abd)) { /* LINTED E_FUNC_SET_NOT_USED */ - size_t index = abd_iter_scatter_chunk_index(aiter); - abd_unmap_chunk( - aiter->iter_abd->abd_u.abd_scatter.abd_chunks[index]); + zfs_kunmap_atomic(aiter->iter_mapaddr - + abd_iter_scatter_chunk_offset(aiter), + km_table[aiter->iter_km]); } ASSERT3P(aiter->iter_mapaddr, !=, NULL); @@ -821,7 +829,7 @@ abd_iterate_func(abd_t *abd, size_t off, size_t size, abd_verify(abd); ASSERT3U(off + size, <=, abd->abd_size); - abd_iter_init(&aiter, abd); + abd_iter_init(&aiter, abd, 0); abd_iter_advance(&aiter, off); while (size > 0) { @@ -953,8 +961,8 @@ abd_iterate_func2(abd_t *dabd, abd_t *sabd, size_t doff, size_t soff, ASSERT3U(doff + size, <=, dabd->abd_size); ASSERT3U(soff + size, <=, sabd->abd_size); - abd_iter_init(&daiter, dabd); - abd_iter_init(&saiter, sabd); + abd_iter_init(&daiter, dabd, 0); + abd_iter_init(&saiter, sabd, 1); abd_iter_advance(&daiter, doff); abd_iter_advance(&saiter, soff); @@ -1039,17 +1047,19 @@ abd_raidz_gen_iterate(abd_t **cabds, abd_t *dabd, struct abd_iter caiters[3]; struct abd_iter daiter; void *caddrs[3]; + unsigned long flags; ASSERT3U(parity, <=, 3); for (i = 0; i < parity; i++) - abd_iter_init(&caiters[i], cabds[i]); + abd_iter_init(&caiters[i], cabds[i], i); if (dabd) - abd_iter_init(&daiter, dabd); + abd_iter_init(&daiter, dabd, i); ASSERT3S(dsize, >=, 0); + local_irq_save(flags); while (csize > 0) { len = csize; @@ -1106,6 +1116,7 @@ abd_raidz_gen_iterate(abd_t **cabds, abd_t *dabd, ASSERT3S(dsize, >=, 0); ASSERT3S(csize, >=, 0); } + local_irq_restore(flags); } /* @@ -1130,14 +1141,16 @@ abd_raidz_rec_iterate(abd_t **cabds, abd_t **tabds, struct abd_iter citers[3]; struct abd_iter xiters[3]; void *caddrs[3], *xaddrs[3]; + unsigned long flags; ASSERT3U(parity, <=, 3); for (i = 0; i < parity; i++) { - abd_iter_init(&citers[i], cabds[i]); - abd_iter_init(&xiters[i], tabds[i]); + abd_iter_init(&citers[i], cabds[i], 2*i); + abd_iter_init(&xiters[i], tabds[i], 2*i+1); } + local_irq_save(flags); while (tsize > 0) { for (i = 0; i < parity; i++) { @@ -1179,6 +1192,7 @@ abd_raidz_rec_iterate(abd_t **cabds, abd_t **tabds, tsize -= len; ASSERT3S(tsize, >=, 0); } + local_irq_restore(flags); } #if defined(_KERNEL) && defined(HAVE_SPL) @@ -1215,7 +1229,7 @@ abd_scatter_bio_map_off(struct bio *bio, abd_t *abd, ASSERT(!abd_is_linear(abd)); ASSERT3U(io_size, <=, abd->abd_size - off); - abd_iter_init(&aiter, abd); + abd_iter_init(&aiter, abd, 0); abd_iter_advance(&aiter, off); for (i = 0; i < bio->bi_max_vecs; i++) {