]>
git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - block/blk-lib.c
2 * Functions related to generic helpers functions
4 #include <linux/kernel.h>
5 #include <linux/module.h>
7 #include <linux/blkdev.h>
8 #include <linux/scatterlist.h>
12 static struct bio
*next_bio(struct bio
*bio
, unsigned int nr_pages
,
15 struct bio
*new = bio_alloc(gfp
, nr_pages
);
25 int __blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
26 sector_t nr_sects
, gfp_t gfp_mask
, int flags
,
29 struct request_queue
*q
= bdev_get_queue(bdev
);
30 struct bio
*bio
= *biop
;
31 unsigned int granularity
;
39 if (flags
& BLKDEV_DISCARD_SECURE
) {
40 if (flags
& BLKDEV_DISCARD_ZERO
)
42 if (!blk_queue_secure_erase(q
))
44 op
= REQ_OP_SECURE_ERASE
;
46 if (!blk_queue_discard(q
))
48 if ((flags
& BLKDEV_DISCARD_ZERO
) &&
49 !q
->limits
.discard_zeroes_data
)
54 bs_mask
= (bdev_logical_block_size(bdev
) >> 9) - 1;
55 if ((sector
| nr_sects
) & bs_mask
)
58 /* Zero-sector (unknown) and one-sector granularities are the same. */
59 granularity
= max(q
->limits
.discard_granularity
>> 9, 1U);
60 alignment
= (bdev_discard_alignment(bdev
) >> 9) % granularity
;
63 unsigned int req_sects
;
64 sector_t end_sect
, tmp
;
66 /* Make sure bi_size doesn't overflow */
67 req_sects
= min_t(sector_t
, nr_sects
, UINT_MAX
>> 9);
70 * If splitting a request, and the next starting sector would be
71 * misaligned, stop the discard at the previous aligned sector.
73 end_sect
= sector
+ req_sects
;
75 if (req_sects
< nr_sects
&&
76 sector_div(tmp
, granularity
) != alignment
) {
77 end_sect
= end_sect
- alignment
;
78 sector_div(end_sect
, granularity
);
79 end_sect
= end_sect
* granularity
+ alignment
;
80 req_sects
= end_sect
- sector
;
83 bio
= next_bio(bio
, 0, gfp_mask
);
84 bio
->bi_iter
.bi_sector
= sector
;
86 bio_set_op_attrs(bio
, op
, 0);
88 bio
->bi_iter
.bi_size
= req_sects
<< 9;
89 nr_sects
-= req_sects
;
93 * We can loop for a long time in here, if someone does
94 * full device discards (like mkfs). Be nice and allow
95 * us to schedule out to avoid softlocking if preempt
104 EXPORT_SYMBOL(__blkdev_issue_discard
);
107 * blkdev_issue_discard - queue a discard
108 * @bdev: blockdev to issue discard for
109 * @sector: start sector
110 * @nr_sects: number of sectors to discard
111 * @gfp_mask: memory allocation flags (for bio_alloc)
112 * @flags: BLKDEV_IFL_* flags to control behaviour
115 * Issue a discard request for the sectors in question.
117 int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
118 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
)
120 struct bio
*bio
= NULL
;
121 struct blk_plug plug
;
124 blk_start_plug(&plug
);
125 ret
= __blkdev_issue_discard(bdev
, sector
, nr_sects
, gfp_mask
, flags
,
128 ret
= submit_bio_wait(bio
);
129 if (ret
== -EOPNOTSUPP
&& !(flags
& BLKDEV_DISCARD_ZERO
))
133 blk_finish_plug(&plug
);
137 EXPORT_SYMBOL(blkdev_issue_discard
);
140 * __blkdev_issue_write_same - generate number of bios with same page
141 * @bdev: target blockdev
142 * @sector: start sector
143 * @nr_sects: number of sectors to write
144 * @gfp_mask: memory allocation flags (for bio_alloc)
145 * @page: page containing data to write
146 * @biop: pointer to anchor bio
149 * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page.
151 static int __blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
152 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
,
155 struct request_queue
*q
= bdev_get_queue(bdev
);
156 unsigned int max_write_same_sectors
;
157 struct bio
*bio
= *biop
;
163 bs_mask
= (bdev_logical_block_size(bdev
) >> 9) - 1;
164 if ((sector
| nr_sects
) & bs_mask
)
167 if (!bdev_write_same(bdev
))
170 /* Ensure that max_write_same_sectors doesn't overflow bi_size */
171 max_write_same_sectors
= UINT_MAX
>> 9;
174 bio
= next_bio(bio
, 1, gfp_mask
);
175 bio
->bi_iter
.bi_sector
= sector
;
178 bio
->bi_io_vec
->bv_page
= page
;
179 bio
->bi_io_vec
->bv_offset
= 0;
180 bio
->bi_io_vec
->bv_len
= bdev_logical_block_size(bdev
);
181 bio_set_op_attrs(bio
, REQ_OP_WRITE_SAME
, 0);
183 if (nr_sects
> max_write_same_sectors
) {
184 bio
->bi_iter
.bi_size
= max_write_same_sectors
<< 9;
185 nr_sects
-= max_write_same_sectors
;
186 sector
+= max_write_same_sectors
;
188 bio
->bi_iter
.bi_size
= nr_sects
<< 9;
199 * blkdev_issue_write_same - queue a write same operation
200 * @bdev: target blockdev
201 * @sector: start sector
202 * @nr_sects: number of sectors to write
203 * @gfp_mask: memory allocation flags (for bio_alloc)
204 * @page: page containing data
207 * Issue a write same request for the sectors in question.
209 int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
210 sector_t nr_sects
, gfp_t gfp_mask
,
213 struct bio
*bio
= NULL
;
214 struct blk_plug plug
;
217 blk_start_plug(&plug
);
218 ret
= __blkdev_issue_write_same(bdev
, sector
, nr_sects
, gfp_mask
, page
,
220 if (ret
== 0 && bio
) {
221 ret
= submit_bio_wait(bio
);
224 blk_finish_plug(&plug
);
227 EXPORT_SYMBOL(blkdev_issue_write_same
);
230 * __blkdev_issue_write_zeroes - generate number of bios with WRITE ZEROES
231 * @bdev: blockdev to issue
232 * @sector: start sector
233 * @nr_sects: number of sectors to write
234 * @gfp_mask: memory allocation flags (for bio_alloc)
235 * @biop: pointer to anchor bio
238 * Generate and issue number of bios(REQ_OP_WRITE_ZEROES) with zerofiled pages.
240 static int __blkdev_issue_write_zeroes(struct block_device
*bdev
,
241 sector_t sector
, sector_t nr_sects
, gfp_t gfp_mask
,
244 struct bio
*bio
= *biop
;
245 unsigned int max_write_zeroes_sectors
;
246 struct request_queue
*q
= bdev_get_queue(bdev
);
251 /* Ensure that max_write_zeroes_sectors doesn't overflow bi_size */
252 max_write_zeroes_sectors
= bdev_write_zeroes_sectors(bdev
);
254 if (max_write_zeroes_sectors
== 0)
258 bio
= next_bio(bio
, 0, gfp_mask
);
259 bio
->bi_iter
.bi_sector
= sector
;
261 bio_set_op_attrs(bio
, REQ_OP_WRITE_ZEROES
, 0);
263 if (nr_sects
> max_write_zeroes_sectors
) {
264 bio
->bi_iter
.bi_size
= max_write_zeroes_sectors
<< 9;
265 nr_sects
-= max_write_zeroes_sectors
;
266 sector
+= max_write_zeroes_sectors
;
268 bio
->bi_iter
.bi_size
= nr_sects
<< 9;
279 * __blkdev_issue_zeroout - generate number of zero filed write bios
280 * @bdev: blockdev to issue
281 * @sector: start sector
282 * @nr_sects: number of sectors to write
283 * @gfp_mask: memory allocation flags (for bio_alloc)
284 * @biop: pointer to anchor bio
285 * @discard: discard flag
288 * Generate and issue number of bios with zerofiled pages.
290 int __blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
291 sector_t nr_sects
, gfp_t gfp_mask
, struct bio
**biop
,
296 struct bio
*bio
= *biop
;
300 bs_mask
= (bdev_logical_block_size(bdev
) >> 9) - 1;
301 if ((sector
| nr_sects
) & bs_mask
)
304 ret
= __blkdev_issue_write_zeroes(bdev
, sector
, nr_sects
, gfp_mask
,
306 if (ret
== 0 || (ret
&& ret
!= -EOPNOTSUPP
))
310 while (nr_sects
!= 0) {
311 bio
= next_bio(bio
, min(nr_sects
, (sector_t
)BIO_MAX_PAGES
),
313 bio
->bi_iter
.bi_sector
= sector
;
315 bio_set_op_attrs(bio
, REQ_OP_WRITE
, 0);
317 while (nr_sects
!= 0) {
318 sz
= min((sector_t
) PAGE_SIZE
>> 9 , nr_sects
);
319 bi_size
= bio_add_page(bio
, ZERO_PAGE(0), sz
<< 9, 0);
320 nr_sects
-= bi_size
>> 9;
321 sector
+= bi_size
>> 9;
322 if (bi_size
< (sz
<< 9))
332 EXPORT_SYMBOL(__blkdev_issue_zeroout
);
335 * blkdev_issue_zeroout - zero-fill a block range
336 * @bdev: blockdev to write
337 * @sector: start sector
338 * @nr_sects: number of sectors to write
339 * @gfp_mask: memory allocation flags (for bio_alloc)
340 * @discard: whether to discard the block range
343 * Zero-fill a block range. If the discard flag is set and the block
344 * device guarantees that subsequent READ operations to the block range
345 * in question will return zeroes, the blocks will be discarded. Should
346 * the discard request fail, if the discard flag is not set, or if
347 * discard_zeroes_data is not supported, this function will resort to
348 * zeroing the blocks manually, thus provisioning (allocating,
349 * anchoring) them. If the block device supports WRITE ZEROES or WRITE SAME
350 * command(s), blkdev_issue_zeroout() will use it to optimize the process of
351 * clearing the block range. Otherwise the zeroing will be performed
352 * using regular WRITE calls.
354 int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
355 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
)
358 struct bio
*bio
= NULL
;
359 struct blk_plug plug
;
362 if (!blkdev_issue_discard(bdev
, sector
, nr_sects
, gfp_mask
,
363 BLKDEV_DISCARD_ZERO
))
367 if (!blkdev_issue_write_same(bdev
, sector
, nr_sects
, gfp_mask
,
371 blk_start_plug(&plug
);
372 ret
= __blkdev_issue_zeroout(bdev
, sector
, nr_sects
, gfp_mask
,
374 if (ret
== 0 && bio
) {
375 ret
= submit_bio_wait(bio
);
378 blk_finish_plug(&plug
);
382 EXPORT_SYMBOL(blkdev_issue_zeroout
);