Blame view
block/bounce.c
5.82 KB
831058dec [PATCH] BLOCK: Se... |
1 2 3 4 |
/* bounce buffer handling for block devices * * - Split from highmem.c */ |
b1de0d139 mm: convert some ... |
5 |
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
831058dec [PATCH] BLOCK: Se... |
6 |
#include <linux/mm.h> |
b95f1b31b mm: Map most file... |
7 |
#include <linux/export.h> |
831058dec [PATCH] BLOCK: Se... |
8 |
#include <linux/swap.h> |
5a0e3ad6a include cleanup: ... |
9 |
#include <linux/gfp.h> |
831058dec [PATCH] BLOCK: Se... |
10 11 12 13 |
#include <linux/bio.h> #include <linux/pagemap.h> #include <linux/mempool.h> #include <linux/blkdev.h> |
66114cad6 writeback: separa... |
14 |
#include <linux/backing-dev.h> |
831058dec [PATCH] BLOCK: Se... |
15 16 17 |
#include <linux/init.h> #include <linux/hash.h> #include <linux/highmem.h> |
3bcfeaf93 block: initialize... |
18 |
#include <linux/bootmem.h> |
b1de0d139 mm: convert some ... |
19 |
#include <linux/printk.h> |
831058dec [PATCH] BLOCK: Se... |
20 |
#include <asm/tlbflush.h> |
55782138e tracing/events: c... |
21 |
#include <trace/events/block.h> |
831058dec [PATCH] BLOCK: Se... |
22 23 24 25 |
#define POOL_SIZE 64 #define ISA_POOL_SIZE 16 static mempool_t *page_pool, *isa_page_pool; |
f10062578 bounce: allow use... |
26 |
#if defined(CONFIG_HIGHMEM) || defined(CONFIG_NEED_BOUNCE_POOL) |
831058dec [PATCH] BLOCK: Se... |
27 28 |
static __init int init_emergency_pool(void) { |
f10062578 bounce: allow use... |
29 |
#if defined(CONFIG_HIGHMEM) && !defined(CONFIG_MEMORY_HOTPLUG) |
3bcfeaf93 block: initialize... |
30 |
if (max_pfn <= max_low_pfn) |
831058dec [PATCH] BLOCK: Se... |
31 |
return 0; |
3bcfeaf93 block: initialize... |
32 |
#endif |
831058dec [PATCH] BLOCK: Se... |
33 34 35 |
page_pool = mempool_create_page_pool(POOL_SIZE, 0); BUG_ON(!page_pool); |
b1de0d139 mm: convert some ... |
36 37 |
pr_info("pool size: %d pages ", POOL_SIZE); |
831058dec [PATCH] BLOCK: Se... |
38 39 40 41 42 |
return 0; } __initcall(init_emergency_pool); |
f10062578 bounce: allow use... |
43 |
#endif |
831058dec [PATCH] BLOCK: Se... |
44 |
|
f10062578 bounce: allow use... |
45 |
#ifdef CONFIG_HIGHMEM |
831058dec [PATCH] BLOCK: Se... |
46 47 48 49 50 51 52 53 54 |
/* * highmem version, map in to vec */ static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom) { unsigned long flags; unsigned char *vto; local_irq_save(flags); |
9b04c5fec mm: remove the se... |
55 |
vto = kmap_atomic(to->bv_page); |
831058dec [PATCH] BLOCK: Se... |
56 |
memcpy(vto + to->bv_offset, vfrom, to->bv_len); |
9b04c5fec mm: remove the se... |
57 |
kunmap_atomic(vto); |
831058dec [PATCH] BLOCK: Se... |
58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 |
local_irq_restore(flags); } #else /* CONFIG_HIGHMEM */ #define bounce_copy_vec(to, vfrom) \ memcpy(page_address((to)->bv_page) + (to)->bv_offset, vfrom, (to)->bv_len) #endif /* CONFIG_HIGHMEM */ /* * allocate pages in the DMA region for the ISA pool */ static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data) { return mempool_alloc_pages(gfp_mask | GFP_DMA, data); } /* * gets called "every" time someone init's a queue with BLK_BOUNCE_ISA * as the max address, so check if the pool has already been created. */ int init_emergency_isa_pool(void) { if (isa_page_pool) return 0; isa_page_pool = mempool_create(ISA_POOL_SIZE, mempool_alloc_pages_isa, mempool_free_pages, (void *) 0); BUG_ON(!isa_page_pool); |
b1de0d139 mm: convert some ... |
88 89 |
pr_info("isa pool size: %d pages ", ISA_POOL_SIZE); |
831058dec [PATCH] BLOCK: Se... |
90 91 92 93 94 95 96 97 98 99 100 |
return 0; } /* * Simple bounce buffer support for highmem pages. Depending on the * queue gfp mask set, *to may or may not be a highmem page. kmap it * always, it will do the Right Thing */ static void copy_to_high_bio_irq(struct bio *to, struct bio *from) { unsigned char *vfrom; |
7988613b0 block: Convert bi... |
101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 |
struct bio_vec tovec, *fromvec = from->bi_io_vec; struct bvec_iter iter; bio_for_each_segment(tovec, to, iter) { if (tovec.bv_page != fromvec->bv_page) { /* * fromvec->bv_offset and fromvec->bv_len might have * been modified by the block layer, so use the original * copy, bounce_copy_vec already uses tovec->bv_len */ vfrom = page_address(fromvec->bv_page) + tovec.bv_offset; bounce_copy_vec(&tovec, vfrom); flush_dcache_page(tovec.bv_page); } |
831058dec [PATCH] BLOCK: Se... |
117 |
|
7988613b0 block: Convert bi... |
118 |
fromvec++; |
831058dec [PATCH] BLOCK: Se... |
119 120 |
} } |
4246a0b63 block: add a bi_e... |
121 |
static void bounce_end_io(struct bio *bio, mempool_t *pool) |
831058dec [PATCH] BLOCK: Se... |
122 123 124 125 |
{ struct bio *bio_orig = bio->bi_private; struct bio_vec *bvec, *org_vec; int i; |
994518799 block: fix bounce... |
126 |
int start = bio_orig->bi_iter.bi_idx; |
831058dec [PATCH] BLOCK: Se... |
127 |
|
831058dec [PATCH] BLOCK: Se... |
128 129 130 |
/* * free up bounce indirect pages used */ |
d74c6d514 block: Add bio_fo... |
131 |
bio_for_each_segment_all(bvec, bio, i) { |
994518799 block: fix bounce... |
132 |
org_vec = bio_orig->bi_io_vec + i + start; |
831058dec [PATCH] BLOCK: Se... |
133 134 135 136 137 138 |
if (bvec->bv_page == org_vec->bv_page) continue; dec_zone_page_state(bvec->bv_page, NR_BOUNCE); mempool_free(bvec->bv_page, pool); } |
4246a0b63 block: add a bi_e... |
139 140 |
bio_orig->bi_error = bio->bi_error; bio_endio(bio_orig); |
831058dec [PATCH] BLOCK: Se... |
141 142 |
bio_put(bio); } |
4246a0b63 block: add a bi_e... |
143 |
static void bounce_end_io_write(struct bio *bio) |
831058dec [PATCH] BLOCK: Se... |
144 |
{ |
4246a0b63 block: add a bi_e... |
145 |
bounce_end_io(bio, page_pool); |
831058dec [PATCH] BLOCK: Se... |
146 |
} |
4246a0b63 block: add a bi_e... |
147 |
static void bounce_end_io_write_isa(struct bio *bio) |
831058dec [PATCH] BLOCK: Se... |
148 |
{ |
831058dec [PATCH] BLOCK: Se... |
149 |
|
4246a0b63 block: add a bi_e... |
150 |
bounce_end_io(bio, isa_page_pool); |
831058dec [PATCH] BLOCK: Se... |
151 |
} |
4246a0b63 block: add a bi_e... |
152 |
static void __bounce_end_io_read(struct bio *bio, mempool_t *pool) |
831058dec [PATCH] BLOCK: Se... |
153 154 |
{ struct bio *bio_orig = bio->bi_private; |
4246a0b63 block: add a bi_e... |
155 |
if (!bio->bi_error) |
831058dec [PATCH] BLOCK: Se... |
156 |
copy_to_high_bio_irq(bio_orig, bio); |
4246a0b63 block: add a bi_e... |
157 |
bounce_end_io(bio, pool); |
831058dec [PATCH] BLOCK: Se... |
158 |
} |
4246a0b63 block: add a bi_e... |
159 |
static void bounce_end_io_read(struct bio *bio) |
831058dec [PATCH] BLOCK: Se... |
160 |
{ |
4246a0b63 block: add a bi_e... |
161 |
__bounce_end_io_read(bio, page_pool); |
831058dec [PATCH] BLOCK: Se... |
162 |
} |
4246a0b63 block: add a bi_e... |
163 |
static void bounce_end_io_read_isa(struct bio *bio) |
831058dec [PATCH] BLOCK: Se... |
164 |
{ |
4246a0b63 block: add a bi_e... |
165 |
__bounce_end_io_read(bio, isa_page_pool); |
831058dec [PATCH] BLOCK: Se... |
166 |
} |
165125e1e [BLOCK] Get rid o... |
167 |
static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, |
a3ad0a9da block: Remove for... |
168 |
mempool_t *pool) |
831058dec [PATCH] BLOCK: Se... |
169 |
{ |
6bc454d15 bounce: Refactor ... |
170 171 |
struct bio *bio; int rw = bio_data_dir(*bio_orig); |
7988613b0 block: Convert bi... |
172 173 |
struct bio_vec *to, from; struct bvec_iter iter; |
6bc454d15 bounce: Refactor ... |
174 |
unsigned i; |
831058dec [PATCH] BLOCK: Se... |
175 |
|
7988613b0 block: Convert bi... |
176 177 |
bio_for_each_segment(from, *bio_orig, iter) if (page_to_pfn(from.bv_page) > queue_bounce_pfn(q)) |
6bc454d15 bounce: Refactor ... |
178 |
goto bounce; |
831058dec [PATCH] BLOCK: Se... |
179 |
|
6bc454d15 bounce: Refactor ... |
180 181 182 |
return; bounce: bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set); |
831058dec [PATCH] BLOCK: Se... |
183 |
|
cb34e057a block: Convert so... |
184 |
bio_for_each_segment_all(to, bio, i) { |
6bc454d15 bounce: Refactor ... |
185 |
struct page *page = to->bv_page; |
f735b5eeb bounce: don't rel... |
186 |
|
a3ad0a9da block: Remove for... |
187 |
if (page_to_pfn(page) <= queue_bounce_pfn(q)) |
6bc454d15 bounce: Refactor ... |
188 |
continue; |
831058dec [PATCH] BLOCK: Se... |
189 |
|
6bc454d15 bounce: Refactor ... |
190 |
to->bv_page = mempool_alloc(pool, q->bounce_gfp); |
393a33970 block:bounce: fix... |
191 |
inc_zone_page_state(to->bv_page, NR_BOUNCE); |
831058dec [PATCH] BLOCK: Se... |
192 193 194 |
if (rw == WRITE) { char *vto, *vfrom; |
6bc454d15 bounce: Refactor ... |
195 |
flush_dcache_page(page); |
831058dec [PATCH] BLOCK: Se... |
196 |
vto = page_address(to->bv_page) + to->bv_offset; |
6bc454d15 bounce: Refactor ... |
197 |
vfrom = kmap_atomic(page) + to->bv_offset; |
831058dec [PATCH] BLOCK: Se... |
198 |
memcpy(vto, vfrom, to->bv_len); |
6bc454d15 bounce: Refactor ... |
199 |
kunmap_atomic(vfrom); |
831058dec [PATCH] BLOCK: Se... |
200 201 |
} } |
5f3ea37c7 blktrace: port to... |
202 |
trace_block_bio_bounce(q, *bio_orig); |
c43a5082a [PATCH] blktrace:... |
203 |
|
831058dec [PATCH] BLOCK: Se... |
204 |
bio->bi_flags |= (1 << BIO_BOUNCED); |
831058dec [PATCH] BLOCK: Se... |
205 206 207 208 209 210 211 212 213 214 215 216 217 218 |
if (pool == page_pool) { bio->bi_end_io = bounce_end_io_write; if (rw == READ) bio->bi_end_io = bounce_end_io_read; } else { bio->bi_end_io = bounce_end_io_write_isa; if (rw == READ) bio->bi_end_io = bounce_end_io_read_isa; } bio->bi_private = *bio_orig; *bio_orig = bio; } |
165125e1e [BLOCK] Get rid o... |
219 |
void blk_queue_bounce(struct request_queue *q, struct bio **bio_orig) |
831058dec [PATCH] BLOCK: Se... |
220 221 222 223 |
{ mempool_t *pool; /* |
bf2de6f5a block: Initial su... |
224 225 |
* Data-less bio, nothing to bounce */ |
36144077b highmem: use bio_... |
226 |
if (!bio_has_data(*bio_orig)) |
bf2de6f5a block: Initial su... |
227 228 229 |
return; /* |
831058dec [PATCH] BLOCK: Se... |
230 231 232 233 234 |
* for non-isa bounce case, just check if the bounce pfn is equal * to or bigger than the highest pfn in the system -- in that case, * don't waste time iterating over bio segments */ if (!(q->bounce_gfp & GFP_DMA)) { |
a3ad0a9da block: Remove for... |
235 |
if (queue_bounce_pfn(q) >= blk_max_pfn) |
831058dec [PATCH] BLOCK: Se... |
236 237 238 239 240 241 |
return; pool = page_pool; } else { BUG_ON(!isa_page_pool); pool = isa_page_pool; } |
831058dec [PATCH] BLOCK: Se... |
242 243 244 |
/* * slow path */ |
a3ad0a9da block: Remove for... |
245 |
__blk_queue_bounce(q, bio_orig, pool); |
831058dec [PATCH] BLOCK: Se... |
246 247 248 |
} EXPORT_SYMBOL(blk_queue_bounce); |