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-rw-r--r--drivers/md/raid5.c119
-rw-r--r--drivers/md/raid5.h4
2 files changed, 101 insertions, 22 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 348a857ab0ff..d69fd9888c2c 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -487,6 +487,7 @@ static void shrink_buffers(struct stripe_head *sh)
int num = sh->raid_conf->pool_size;
for (i = 0; i < num ; i++) {
+ WARN_ON(sh->dev[i].page != sh->dev[i].orig_page);
p = sh->dev[i].page;
if (!p)
continue;
@@ -507,6 +508,7 @@ static int grow_buffers(struct stripe_head *sh)
return 1;
}
sh->dev[i].page = page;
+ sh->dev[i].orig_page = page;
}
return 0;
}
@@ -863,6 +865,9 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
bi->bi_rw |= REQ_NOMERGE;
+ if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
+ WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
+ sh->dev[i].vec.bv_page = sh->dev[i].page;
bi->bi_vcnt = 1;
bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
bi->bi_io_vec[0].bv_offset = 0;
@@ -907,6 +912,9 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
else
rbi->bi_iter.bi_sector = (sh->sector
+ rrdev->data_offset);
+ if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
+ WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
+ sh->dev[i].rvec.bv_page = sh->dev[i].page;
rbi->bi_vcnt = 1;
rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
rbi->bi_io_vec[0].bv_offset = 0;
@@ -935,8 +943,9 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
}
static struct dma_async_tx_descriptor *
-async_copy_data(int frombio, struct bio *bio, struct page *page,
- sector_t sector, struct dma_async_tx_descriptor *tx)
+async_copy_data(int frombio, struct bio *bio, struct page **page,
+ sector_t sector, struct dma_async_tx_descriptor *tx,
+ struct stripe_head *sh)
{
struct bio_vec bvl;
struct bvec_iter iter;
@@ -973,11 +982,16 @@ async_copy_data(int frombio, struct bio *bio, struct page *page,
if (clen > 0) {
b_offset += bvl.bv_offset;
bio_page = bvl.bv_page;
- if (frombio)
- tx = async_memcpy(page, bio_page, page_offset,
+ if (frombio) {
+ if (sh->raid_conf->skip_copy &&
+ b_offset == 0 && page_offset == 0 &&
+ clen == STRIPE_SIZE)
+ *page = bio_page;
+ else
+ tx = async_memcpy(*page, bio_page, page_offset,
b_offset, clen, &submit);
- else
- tx = async_memcpy(bio_page, page, b_offset,
+ } else
+ tx = async_memcpy(bio_page, *page, b_offset,
page_offset, clen, &submit);
}
/* chain the operations */
@@ -1053,8 +1067,8 @@ static void ops_run_biofill(struct stripe_head *sh)
spin_unlock_irq(&sh->stripe_lock);
while (rbi && rbi->bi_iter.bi_sector <
dev->sector + STRIPE_SECTORS) {
- tx = async_copy_data(0, rbi, dev->page,
- dev->sector, tx);
+ tx = async_copy_data(0, rbi, &dev->page,
+ dev->sector, tx, sh);
rbi = r5_next_bio(rbi, dev->sector);
}
}
@@ -1392,6 +1406,7 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
BUG_ON(dev->written);
wbi = dev->written = chosen;
spin_unlock_irq(&sh->stripe_lock);
+ WARN_ON(dev->page != dev->orig_page);
while (wbi && wbi->bi_iter.bi_sector <
dev->sector + STRIPE_SECTORS) {
@@ -1401,9 +1416,15 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
set_bit(R5_SyncIO, &dev->flags);
if (wbi->bi_rw & REQ_DISCARD)
set_bit(R5_Discard, &dev->flags);
- else
- tx = async_copy_data(1, wbi, dev->page,
- dev->sector, tx);
+ else {
+ tx = async_copy_data(1, wbi, &dev->page,
+ dev->sector, tx, sh);
+ if (dev->page != dev->orig_page) {
+ set_bit(R5_SkipCopy, &dev->flags);
+ clear_bit(R5_UPTODATE, &dev->flags);
+ clear_bit(R5_OVERWRITE, &dev->flags);
+ }
+ }
wbi = r5_next_bio(wbi, dev->sector);
}
}
@@ -1434,7 +1455,7 @@ static void ops_complete_reconstruct(void *stripe_head_ref)
struct r5dev *dev = &sh->dev[i];
if (dev->written || i == pd_idx || i == qd_idx) {
- if (!discard)
+ if (!discard && !test_bit(R5_SkipCopy, &dev->flags))
set_bit(R5_UPTODATE, &dev->flags);
if (fua)
set_bit(R5_WantFUA, &dev->flags);
@@ -1847,8 +1868,10 @@ static int resize_stripes(struct r5conf *conf, int newsize)
osh = get_free_stripe(conf, hash);
unlock_device_hash_lock(conf, hash);
atomic_set(&nsh->count, 1);
- for(i=0; i<conf->pool_size; i++)
+ for(i=0; i<conf->pool_size; i++) {
nsh->dev[i].page = osh->dev[i].page;
+ nsh->dev[i].orig_page = osh->dev[i].page;
+ }
for( ; i<newsize; i++)
nsh->dev[i].page = NULL;
nsh->hash_lock_index = hash;
@@ -1904,6 +1927,7 @@ static int resize_stripes(struct r5conf *conf, int newsize)
if (nsh->dev[i].page == NULL) {
struct page *p = alloc_page(GFP_NOIO);
nsh->dev[i].page = p;
+ nsh->dev[i].orig_page = p;
if (!p)
err = -ENOMEM;
}
@@ -2141,24 +2165,20 @@ static void raid5_end_write_request(struct bio *bi, int error)
}
static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous);
-
+
static void raid5_build_block(struct stripe_head *sh, int i, int previous)
{
struct r5dev *dev = &sh->dev[i];
bio_init(&dev->req);
dev->req.bi_io_vec = &dev->vec;
- dev->req.bi_vcnt++;
- dev->req.bi_max_vecs++;
+ dev->req.bi_max_vecs = 1;
dev->req.bi_private = sh;
- dev->vec.bv_page = dev->page;
bio_init(&dev->rreq);
dev->rreq.bi_io_vec = &dev->rvec;
- dev->rreq.bi_vcnt++;
- dev->rreq.bi_max_vecs++;
+ dev->rreq.bi_max_vecs = 1;
dev->rreq.bi_private = sh;
- dev->rvec.bv_page = dev->page;
dev->flags = 0;
dev->sector = compute_blocknr(sh, i, previous);
@@ -2758,6 +2778,11 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
/* and fail all 'written' */
bi = sh->dev[i].written;
sh->dev[i].written = NULL;
+ if (test_and_clear_bit(R5_SkipCopy, &sh->dev[i].flags)) {
+ WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
+ sh->dev[i].page = sh->dev[i].orig_page;
+ }
+
if (bi) bitmap_end = 1;
while (bi && bi->bi_iter.bi_sector <
sh->dev[i].sector + STRIPE_SECTORS) {
@@ -3002,12 +3027,17 @@ static void handle_stripe_clean_event(struct r5conf *conf,
dev = &sh->dev[i];
if (!test_bit(R5_LOCKED, &dev->flags) &&
(test_bit(R5_UPTODATE, &dev->flags) ||
- test_bit(R5_Discard, &dev->flags))) {
+ test_bit(R5_Discard, &dev->flags) ||
+ test_bit(R5_SkipCopy, &dev->flags))) {
/* We can return any write requests */
struct bio *wbi, *wbi2;
pr_debug("Return write for disc %d\n", i);
if (test_and_clear_bit(R5_Discard, &dev->flags))
clear_bit(R5_UPTODATE, &dev->flags);
+ if (test_and_clear_bit(R5_SkipCopy, &dev->flags)) {
+ WARN_ON(test_bit(R5_UPTODATE, &dev->flags));
+ dev->page = dev->orig_page;
+ }
wbi = dev->written;
dev->written = NULL;
while (wbi && wbi->bi_iter.bi_sector <
@@ -3026,6 +3056,8 @@ static void handle_stripe_clean_event(struct r5conf *conf,
0);
} else if (test_bit(R5_Discard, &dev->flags))
discard_pending = 1;
+ WARN_ON(test_bit(R5_SkipCopy, &dev->flags));
+ WARN_ON(dev->page != dev->orig_page);
}
if (!discard_pending &&
test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags)) {
@@ -5366,6 +5398,50 @@ raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold,
raid5_store_preread_threshold);
static ssize_t
+raid5_show_skip_copy(struct mddev *mddev, char *page)
+{
+ struct r5conf *conf = mddev->private;
+ if (conf)
+ return sprintf(page, "%d\n", conf->skip_copy);
+ else
+ return 0;
+}
+
+static ssize_t
+raid5_store_skip_copy(struct mddev *mddev, const char *page, size_t len)
+{
+ struct r5conf *conf = mddev->private;
+ unsigned long new;
+ if (len >= PAGE_SIZE)
+ return -EINVAL;
+ if (!conf)
+ return -ENODEV;
+
+ if (kstrtoul(page, 10, &new))
+ return -EINVAL;
+ new = !!new;
+ if (new == conf->skip_copy)
+ return len;
+
+ mddev_suspend(mddev);
+ conf->skip_copy = new;
+ if (new)
+ mddev->queue->backing_dev_info.capabilities |=
+ BDI_CAP_STABLE_WRITES;
+ else
+ mddev->queue->backing_dev_info.capabilities &=
+ ~BDI_CAP_STABLE_WRITES;
+ mddev_resume(mddev);
+ return len;
+}
+
+static struct md_sysfs_entry
+raid5_skip_copy = __ATTR(skip_copy, S_IRUGO | S_IWUSR,
+ raid5_show_skip_copy,
+ raid5_store_skip_copy);
+
+
+static ssize_t
stripe_cache_active_show(struct mddev *mddev, char *page)
{
struct r5conf *conf = mddev->private;
@@ -5450,6 +5526,7 @@ static struct attribute *raid5_attrs[] = {
&raid5_stripecache_active.attr,
&raid5_preread_bypass_threshold.attr,
&raid5_group_thread_cnt.attr,
+ &raid5_skip_copy.attr,
NULL,
};
static struct attribute_group raid5_attrs_group = {
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 01ad8ae8f578..bc72cd4be5f8 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -232,7 +232,7 @@ struct stripe_head {
*/
struct bio req, rreq;
struct bio_vec vec, rvec;
- struct page *page;
+ struct page *page, *orig_page;
struct bio *toread, *read, *towrite, *written;
sector_t sector; /* sector of this page */
unsigned long flags;
@@ -299,6 +299,7 @@ enum r5dev_flags {
* data in, and now is a good time to write it out.
*/
R5_Discard, /* Discard the stripe */
+ R5_SkipCopy, /* Don't copy data from bio to stripe cache */
};
/*
@@ -436,6 +437,7 @@ struct r5conf {
atomic_t pending_full_writes; /* full write backlog */
int bypass_count; /* bypassed prereads */
int bypass_threshold; /* preread nice */
+ int skip_copy; /* Don't copy data from bio to stripe cache */
struct list_head *last_hold; /* detect hold_list promotions */
atomic_t reshape_stripes; /* stripes with pending writes for reshape */
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