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authorMartin K. Petersen <martin.petersen@oracle.com>2009-06-26 09:37:49 -0400
committerJens Axboe <jens.axboe@oracle.com>2009-07-01 04:56:25 -0400
commit7878cba9f0037f5599004b03a1260b32d9050360 (patch)
treebff5e1a47b6e64e45df0428925cc6db8542cad62 /fs/bio-integrity.c
parent6118b70b3a0b4c583439bb77600194c82f220ce3 (diff)
block: Create bip slabs with embedded integrity vectors
This patch restores stacking ability to the block layer integrity infrastructure by creating a set of dedicated bip slabs. Each bip slab has an embedded bio_vec array at the end. This cuts down on memory allocations and also simplifies the code compared to the original bvec version. Only the largest bip slab is backed by a mempool. The pool is contained in the bio_set so stacking drivers can ensure forward progress. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@carl.(none)>
Diffstat (limited to 'fs/bio-integrity.c')
-rw-r--r--fs/bio-integrity.c170
1 files changed, 125 insertions, 45 deletions
diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
index 31c46a241bac..49a34e7f7306 100644
--- a/fs/bio-integrity.c
+++ b/fs/bio-integrity.c
@@ -1,7 +1,7 @@
1/* 1/*
2 * bio-integrity.c - bio data integrity extensions 2 * bio-integrity.c - bio data integrity extensions
3 * 3 *
4 * Copyright (C) 2007, 2008 Oracle Corporation 4 * Copyright (C) 2007, 2008, 2009 Oracle Corporation
5 * Written by: Martin K. Petersen <martin.petersen@oracle.com> 5 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
6 * 6 *
7 * This program is free software; you can redistribute it and/or 7 * This program is free software; you can redistribute it and/or
@@ -25,63 +25,121 @@
25#include <linux/bio.h> 25#include <linux/bio.h>
26#include <linux/workqueue.h> 26#include <linux/workqueue.h>
27 27
28static struct kmem_cache *bio_integrity_slab __read_mostly; 28struct integrity_slab {
29static mempool_t *bio_integrity_pool; 29 struct kmem_cache *slab;
30static struct bio_set *integrity_bio_set; 30 unsigned short nr_vecs;
31 char name[8];
32};
33
34#define IS(x) { .nr_vecs = x, .name = "bip-"__stringify(x) }
35struct integrity_slab bip_slab[BIOVEC_NR_POOLS] __read_mostly = {
36 IS(1), IS(4), IS(16), IS(64), IS(128), IS(BIO_MAX_PAGES),
37};
38#undef IS
39
31static struct workqueue_struct *kintegrityd_wq; 40static struct workqueue_struct *kintegrityd_wq;
32 41
42static inline unsigned int vecs_to_idx(unsigned int nr)
43{
44 switch (nr) {
45 case 1:
46 return 0;
47 case 2 ... 4:
48 return 1;
49 case 5 ... 16:
50 return 2;
51 case 17 ... 64:
52 return 3;
53 case 65 ... 128:
54 return 4;
55 case 129 ... BIO_MAX_PAGES:
56 return 5;
57 default:
58 BUG();
59 }
60}
61
62static inline int use_bip_pool(unsigned int idx)
63{
64 if (idx == BIOVEC_NR_POOLS)
65 return 1;
66
67 return 0;
68}
69
33/** 70/**
34 * bio_integrity_alloc - Allocate integrity payload and attach it to bio 71 * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio
35 * @bio: bio to attach integrity metadata to 72 * @bio: bio to attach integrity metadata to
36 * @gfp_mask: Memory allocation mask 73 * @gfp_mask: Memory allocation mask
37 * @nr_vecs: Number of integrity metadata scatter-gather elements 74 * @nr_vecs: Number of integrity metadata scatter-gather elements
75 * @bs: bio_set to allocate from
38 * 76 *
39 * Description: This function prepares a bio for attaching integrity 77 * Description: This function prepares a bio for attaching integrity
40 * metadata. nr_vecs specifies the maximum number of pages containing 78 * metadata. nr_vecs specifies the maximum number of pages containing
41 * integrity metadata that can be attached. 79 * integrity metadata that can be attached.
42 */ 80 */
43struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, 81struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
44 gfp_t gfp_mask, 82 gfp_t gfp_mask,
45 unsigned int nr_vecs) 83 unsigned int nr_vecs,
84 struct bio_set *bs)
46{ 85{
47 struct bio_integrity_payload *bip; 86 struct bio_integrity_payload *bip;
48 struct bio_vec *iv; 87 unsigned int idx = vecs_to_idx(nr_vecs);
49 unsigned long idx;
50 88
51 BUG_ON(bio == NULL); 89 BUG_ON(bio == NULL);
90 bip = NULL;
52 91
53 bip = mempool_alloc(bio_integrity_pool, gfp_mask); 92 /* Lower order allocations come straight from slab */
54 if (unlikely(bip == NULL)) { 93 if (!use_bip_pool(idx))
55 printk(KERN_ERR "%s: could not alloc bip\n", __func__); 94 bip = kmem_cache_alloc(bip_slab[idx].slab, gfp_mask);
56 return NULL;
57 }
58 95
59 memset(bip, 0, sizeof(*bip)); 96 /* Use mempool if lower order alloc failed or max vecs were requested */
97 if (bip == NULL) {
98 bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
60 99
61 iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, integrity_bio_set); 100 if (unlikely(bip == NULL)) {
62 if (unlikely(iv == NULL)) { 101 printk(KERN_ERR "%s: could not alloc bip\n", __func__);
63 printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__); 102 return NULL;
64 mempool_free(bip, bio_integrity_pool); 103 }
65 return NULL;
66 } 104 }
67 105
68 bip->bip_pool = idx; 106 memset(bip, 0, sizeof(*bip));
69 bip->bip_vec = iv; 107
108 bip->bip_slab = idx;
70 bip->bip_bio = bio; 109 bip->bip_bio = bio;
71 bio->bi_integrity = bip; 110 bio->bi_integrity = bip;
72 111
73 return bip; 112 return bip;
74} 113}
114EXPORT_SYMBOL(bio_integrity_alloc_bioset);
115
116/**
117 * bio_integrity_alloc - Allocate integrity payload and attach it to bio
118 * @bio: bio to attach integrity metadata to
119 * @gfp_mask: Memory allocation mask
120 * @nr_vecs: Number of integrity metadata scatter-gather elements
121 *
122 * Description: This function prepares a bio for attaching integrity
123 * metadata. nr_vecs specifies the maximum number of pages containing
124 * integrity metadata that can be attached.
125 */
126struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
127 gfp_t gfp_mask,
128 unsigned int nr_vecs)
129{
130 return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set);
131}
75EXPORT_SYMBOL(bio_integrity_alloc); 132EXPORT_SYMBOL(bio_integrity_alloc);
76 133
77/** 134/**
78 * bio_integrity_free - Free bio integrity payload 135 * bio_integrity_free - Free bio integrity payload
79 * @bio: bio containing bip to be freed 136 * @bio: bio containing bip to be freed
137 * @bs: bio_set this bio was allocated from
80 * 138 *
81 * Description: Used to free the integrity portion of a bio. Usually 139 * Description: Used to free the integrity portion of a bio. Usually
82 * called from bio_free(). 140 * called from bio_free().
83 */ 141 */
84void bio_integrity_free(struct bio *bio) 142void bio_integrity_free(struct bio *bio, struct bio_set *bs)
85{ 143{
86 struct bio_integrity_payload *bip = bio->bi_integrity; 144 struct bio_integrity_payload *bip = bio->bi_integrity;
87 145
@@ -92,8 +150,10 @@ void bio_integrity_free(struct bio *bio)
92 && bip->bip_buf != NULL) 150 && bip->bip_buf != NULL)
93 kfree(bip->bip_buf); 151 kfree(bip->bip_buf);
94 152
95 bvec_free_bs(integrity_bio_set, bip->bip_vec, bip->bip_pool); 153 if (use_bip_pool(bip->bip_slab))
96 mempool_free(bip, bio_integrity_pool); 154 mempool_free(bip, bs->bio_integrity_pool);
155 else
156 kmem_cache_free(bip_slab[bip->bip_slab].slab, bip);
97 157
98 bio->bi_integrity = NULL; 158 bio->bi_integrity = NULL;
99} 159}
@@ -114,7 +174,7 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
114 struct bio_integrity_payload *bip = bio->bi_integrity; 174 struct bio_integrity_payload *bip = bio->bi_integrity;
115 struct bio_vec *iv; 175 struct bio_vec *iv;
116 176
117 if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) { 177 if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) {
118 printk(KERN_ERR "%s: bip_vec full\n", __func__); 178 printk(KERN_ERR "%s: bip_vec full\n", __func__);
119 return 0; 179 return 0;
120 } 180 }
@@ -647,8 +707,8 @@ void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
647 bp->iv1 = bip->bip_vec[0]; 707 bp->iv1 = bip->bip_vec[0];
648 bp->iv2 = bip->bip_vec[0]; 708 bp->iv2 = bip->bip_vec[0];
649 709
650 bp->bip1.bip_vec = &bp->iv1; 710 bp->bip1.bip_vec[0] = bp->iv1;
651 bp->bip2.bip_vec = &bp->iv2; 711 bp->bip2.bip_vec[0] = bp->iv2;
652 712
653 bp->iv1.bv_len = sectors * bi->tuple_size; 713 bp->iv1.bv_len = sectors * bi->tuple_size;
654 bp->iv2.bv_offset += sectors * bi->tuple_size; 714 bp->iv2.bv_offset += sectors * bi->tuple_size;
@@ -667,17 +727,19 @@ EXPORT_SYMBOL(bio_integrity_split);
667 * @bio: New bio 727 * @bio: New bio
668 * @bio_src: Original bio 728 * @bio_src: Original bio
669 * @gfp_mask: Memory allocation mask 729 * @gfp_mask: Memory allocation mask
730 * @bs: bio_set to allocate bip from
670 * 731 *
671 * Description: Called to allocate a bip when cloning a bio 732 * Description: Called to allocate a bip when cloning a bio
672 */ 733 */
673int bio_integrity_clone(struct bio *bio, struct bio *bio_src, gfp_t gfp_mask) 734int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
735 gfp_t gfp_mask, struct bio_set *bs)
674{ 736{
675 struct bio_integrity_payload *bip_src = bio_src->bi_integrity; 737 struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
676 struct bio_integrity_payload *bip; 738 struct bio_integrity_payload *bip;
677 739
678 BUG_ON(bip_src == NULL); 740 BUG_ON(bip_src == NULL);
679 741
680 bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt); 742 bip = bio_integrity_alloc_bioset(bio, gfp_mask, bip_src->bip_vcnt, bs);
681 743
682 if (bip == NULL) 744 if (bip == NULL)
683 return -EIO; 745 return -EIO;
@@ -693,25 +755,43 @@ int bio_integrity_clone(struct bio *bio, struct bio *bio_src, gfp_t gfp_mask)
693} 755}
694EXPORT_SYMBOL(bio_integrity_clone); 756EXPORT_SYMBOL(bio_integrity_clone);
695 757
696static int __init bio_integrity_init(void) 758int bioset_integrity_create(struct bio_set *bs, int pool_size)
697{ 759{
698 kintegrityd_wq = create_workqueue("kintegrityd"); 760 unsigned int max_slab = vecs_to_idx(BIO_MAX_PAGES);
761
762 bs->bio_integrity_pool =
763 mempool_create_slab_pool(pool_size, bip_slab[max_slab].slab);
699 764
765 if (!bs->bio_integrity_pool)
766 return -1;
767
768 return 0;
769}
770EXPORT_SYMBOL(bioset_integrity_create);
771
772void bioset_integrity_free(struct bio_set *bs)
773{
774 if (bs->bio_integrity_pool)
775 mempool_destroy(bs->bio_integrity_pool);
776}
777EXPORT_SYMBOL(bioset_integrity_free);
778
779void __init bio_integrity_init(void)
780{
781 unsigned int i;
782
783 kintegrityd_wq = create_workqueue("kintegrityd");
700 if (!kintegrityd_wq) 784 if (!kintegrityd_wq)
701 panic("Failed to create kintegrityd\n"); 785 panic("Failed to create kintegrityd\n");
702 786
703 bio_integrity_slab = KMEM_CACHE(bio_integrity_payload, 787 for (i = 0 ; i < BIOVEC_NR_POOLS ; i++) {
704 SLAB_HWCACHE_ALIGN|SLAB_PANIC); 788 unsigned int size;
705 789
706 bio_integrity_pool = mempool_create_slab_pool(BIO_POOL_SIZE, 790 size = sizeof(struct bio_integrity_payload)
707 bio_integrity_slab); 791 + bip_slab[i].nr_vecs * sizeof(struct bio_vec);
708 if (!bio_integrity_pool)
709 panic("bio_integrity: can't allocate bip pool\n");
710 792
711 integrity_bio_set = bioset_create(BIO_POOL_SIZE, 0); 793 bip_slab[i].slab =
712 if (!integrity_bio_set) 794 kmem_cache_create(bip_slab[i].name, size, 0,
713 panic("bio_integrity: can't allocate bio_set\n"); 795 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
714 796 }
715 return 0;
716} 797}
717subsys_initcall(bio_integrity_init);