From 7aba13b7152979450270da5602f16f6f28fd35b8 Mon Sep 17 00:00:00 2001 From: Yufen Yu Date: Thu, 20 Aug 2020 09:22:06 -0400 Subject: [PATCH] md/raid5: add a new member of offset into r5dev Add a new member of offset into struct r5dev. It indicates the offset of related dev[i].page. For now, since each device have a privated page, the value is always 0. Thus, we set offset as 0 when allcate page in grow_buffers() and resize_stripes(). To support following different page offset, we try to use the page offset rather than '0' directly for async_memcpy() and ops_run_io(). We try to support different page offset for xor compution functions in the following. To avoid repeatly allocate a new array each time, we add a memory region into scribble buffer to record offset. No functional change. Signed-off-by: Yufen Yu Signed-off-by: Song Liu --- drivers/md/raid5.c | 50 ++++++++++++++++++++++++++++++++++++---------- drivers/md/raid5.h | 1 + 2 files changed, 40 insertions(+), 11 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index d589d26c86ea..b64f56c87339 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -477,6 +477,7 @@ static int grow_buffers(struct stripe_head *sh, gfp_t gfp) } sh->dev[i].page = page; sh->dev[i].orig_page = page; + sh->dev[i].offset = 0; } return 0; @@ -1130,7 +1131,7 @@ again: sh->dev[i].vec.bv_page = sh->dev[i].page; bi->bi_vcnt = 1; bi->bi_io_vec[0].bv_len = RAID5_STRIPE_SIZE(conf); - bi->bi_io_vec[0].bv_offset = 0; + bi->bi_io_vec[0].bv_offset = sh->dev[i].offset; bi->bi_iter.bi_size = RAID5_STRIPE_SIZE(conf); bi->bi_write_hint = sh->dev[i].write_hint; if (!rrdev) @@ -1184,7 +1185,7 @@ again: sh->dev[i].rvec.bv_page = sh->dev[i].page; rbi->bi_vcnt = 1; rbi->bi_io_vec[0].bv_len = RAID5_STRIPE_SIZE(conf); - rbi->bi_io_vec[0].bv_offset = 0; + rbi->bi_io_vec[0].bv_offset = sh->dev[i].offset; rbi->bi_iter.bi_size = RAID5_STRIPE_SIZE(conf); rbi->bi_write_hint = sh->dev[i].write_hint; sh->dev[i].write_hint = RWH_WRITE_LIFE_NOT_SET; @@ -1404,14 +1405,25 @@ static addr_conv_t *to_addr_conv(struct stripe_head *sh, return (void *) (to_addr_page(percpu, i) + sh->disks + 2); } +/* + * Return a pointer to record offset address. + */ +static unsigned int * +to_addr_offs(struct stripe_head *sh, struct raid5_percpu *percpu) +{ + return (unsigned int *) (to_addr_conv(sh, percpu, 0) + sh->disks + 2); +} + static struct dma_async_tx_descriptor * ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) { int disks = sh->disks; struct page **xor_srcs = to_addr_page(percpu, 0); + unsigned int *off_srcs = to_addr_offs(sh, percpu); int target = sh->ops.target; struct r5dev *tgt = &sh->dev[target]; struct page *xor_dest = tgt->page; + unsigned int off_dest = tgt->offset; int count = 0; struct dma_async_tx_descriptor *tx; struct async_submit_ctl submit; @@ -1423,16 +1435,19 @@ ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) __func__, (unsigned long long)sh->sector, target); BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); - for (i = disks; i--; ) - if (i != target) + for (i = disks; i--; ) { + if (i != target) { + off_srcs[count] = sh->dev[i].offset; xor_srcs[count++] = sh->dev[i].page; + } + } atomic_inc(&sh->count); init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL, ops_complete_compute, sh, to_addr_conv(sh, percpu, 0)); if (unlikely(count == 1)) - tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, + tx = async_memcpy(xor_dest, xor_srcs[0], off_dest, off_srcs[0], RAID5_STRIPE_SIZE(sh->raid_conf), &submit); else tx = async_xor(xor_dest, xor_srcs, 0, count, @@ -1854,9 +1869,11 @@ ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu, { int disks = sh->disks; struct page **xor_srcs; + unsigned int *off_srcs; struct async_submit_ctl submit; int count, pd_idx = sh->pd_idx, i; struct page *xor_dest; + unsigned int off_dest; int prexor = 0; unsigned long flags; int j = 0; @@ -1881,24 +1898,31 @@ ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu, again: count = 0; xor_srcs = to_addr_page(percpu, j); + off_srcs = to_addr_offs(sh, percpu); /* check if prexor is active which means only process blocks * that are part of a read-modify-write (written) */ if (head_sh->reconstruct_state == reconstruct_state_prexor_drain_run) { prexor = 1; + off_dest = off_srcs[count] = sh->dev[pd_idx].offset; xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; for (i = disks; i--; ) { struct r5dev *dev = &sh->dev[i]; if (head_sh->dev[i].written || - test_bit(R5_InJournal, &head_sh->dev[i].flags)) + test_bit(R5_InJournal, &head_sh->dev[i].flags)) { + off_srcs[count] = dev->offset; xor_srcs[count++] = dev->page; + } } } else { xor_dest = sh->dev[pd_idx].page; + off_dest = sh->dev[pd_idx].offset; for (i = disks; i--; ) { struct r5dev *dev = &sh->dev[i]; - if (i != pd_idx) + if (i != pd_idx) { + off_srcs[count] = dev->offset; xor_srcs[count++] = dev->page; + } } } @@ -1924,7 +1948,7 @@ again: } if (unlikely(count == 1)) - tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, + tx = async_memcpy(xor_dest, xor_srcs[0], off_dest, off_srcs[0], RAID5_STRIPE_SIZE(sh->raid_conf), &submit); else tx = async_xor(xor_dest, xor_srcs, 0, count, @@ -2253,8 +2277,9 @@ static int scribble_alloc(struct raid5_percpu *percpu, int num, int cnt) { size_t obj_size = - sizeof(struct page *) * (num+2) + - sizeof(addr_conv_t) * (num+2); + sizeof(struct page *) * (num + 2) + + sizeof(addr_conv_t) * (num + 2) + + sizeof(unsigned int) * (num + 2); void *scribble; /* @@ -2389,6 +2414,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) for(i=0; ipool_size; i++) { nsh->dev[i].page = osh->dev[i].page; nsh->dev[i].orig_page = osh->dev[i].page; + nsh->dev[i].offset = osh->dev[i].offset; } nsh->hash_lock_index = hash; free_stripe(conf->slab_cache, osh); @@ -2444,6 +2470,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) struct page *p = alloc_page(GFP_NOIO); nsh->dev[i].page = p; nsh->dev[i].orig_page = p; + nsh->dev[i].offset = 0; if (!p) err = -ENOMEM; } @@ -4369,7 +4396,8 @@ static void handle_stripe_expansion(struct r5conf *conf, struct stripe_head *sh) /* place all the copies on one channel */ init_async_submit(&submit, 0, tx, NULL, NULL, NULL); tx = async_memcpy(sh2->dev[dd_idx].page, - sh->dev[i].page, 0, 0, RAID5_STRIPE_SIZE(conf), + sh->dev[i].page, sh2->dev[dd_idx].offset, + sh->dev[i].offset, RAID5_STRIPE_SIZE(conf), &submit); set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 16fc29472f5c..6afdd3a78580 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -253,6 +253,7 @@ struct stripe_head { struct bio req, rreq; struct bio_vec vec, rvec; struct page *page, *orig_page; + unsigned int offset; /* offset of the page */ struct bio *toread, *read, *towrite, *written; sector_t sector; /* sector of this page */ unsigned long flags;