diff options
-rw-r--r-- | drivers/md/raid5.c | 132 | ||||
-rw-r--r-- | drivers/md/raid5.h | 8 |
2 files changed, 110 insertions, 30 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 5359236a1ec7..7727954cf726 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -642,11 +642,18 @@ static void ops_complete_compute5(void *stripe_head_ref) release_stripe(sh); } -static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) +/* return a pointer to the address conversion region of the scribble buffer */ +static addr_conv_t *to_addr_conv(struct stripe_head *sh, + struct raid5_percpu *percpu) +{ + return percpu->scribble + sizeof(struct page *) * (sh->disks + 2); +} + +static struct dma_async_tx_descriptor * +ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) { - /* kernel stack size limits the total number of disks */ int disks = sh->disks; - struct page *xor_srcs[disks]; + struct page **xor_srcs = percpu->scribble; int target = sh->ops.target; struct r5dev *tgt = &sh->dev[target]; struct page *xor_dest = tgt->page; @@ -666,7 +673,7 @@ static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) atomic_inc(&sh->count); init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, - ops_complete_compute5, sh, NULL); + ops_complete_compute5, sh, to_addr_conv(sh, percpu)); if (unlikely(count == 1)) tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit); else @@ -684,11 +691,11 @@ static void ops_complete_prexor(void *stripe_head_ref) } static struct dma_async_tx_descriptor * -ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) +ops_run_prexor(struct stripe_head *sh, struct raid5_percpu *percpu, + struct dma_async_tx_descriptor *tx) { - /* kernel stack size limits the total number of disks */ int disks = sh->disks; - struct page *xor_srcs[disks]; + struct page **xor_srcs = percpu->scribble; int count = 0, pd_idx = sh->pd_idx, i; struct async_submit_ctl submit; @@ -706,7 +713,7 @@ ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) } init_async_submit(&submit, ASYNC_TX_XOR_DROP_DST, tx, - ops_complete_prexor, sh, NULL); + ops_complete_prexor, sh, to_addr_conv(sh, percpu)); tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit); return tx; @@ -775,11 +782,11 @@ static void ops_complete_postxor(void *stripe_head_ref) } static void -ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) +ops_run_postxor(struct stripe_head *sh, struct raid5_percpu *percpu, + struct dma_async_tx_descriptor *tx) { - /* kernel stack size limits the total number of disks */ int disks = sh->disks; - struct page *xor_srcs[disks]; + struct page **xor_srcs = percpu->scribble; struct async_submit_ctl submit; int count = 0, pd_idx = sh->pd_idx, i; struct page *xor_dest; @@ -819,7 +826,8 @@ ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) atomic_inc(&sh->count); - init_async_submit(&submit, flags, tx, ops_complete_postxor, sh, NULL); + init_async_submit(&submit, flags, tx, ops_complete_postxor, sh, + to_addr_conv(sh, percpu)); if (unlikely(count == 1)) tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit); else @@ -838,11 +846,10 @@ static void ops_complete_check(void *stripe_head_ref) release_stripe(sh); } -static void ops_run_check(struct stripe_head *sh) +static void ops_run_check(struct stripe_head *sh, struct raid5_percpu *percpu) { - /* kernel stack size limits the total number of disks */ int disks = sh->disks; - struct page *xor_srcs[disks]; + struct page **xor_srcs = percpu->scribble; struct dma_async_tx_descriptor *tx; struct async_submit_ctl submit; @@ -858,7 +865,8 @@ static void ops_run_check(struct stripe_head *sh) xor_srcs[count++] = dev->page; } - init_async_submit(&submit, 0, NULL, NULL, NULL, NULL); + init_async_submit(&submit, 0, NULL, NULL, NULL, + to_addr_conv(sh, percpu)); tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &sh->ops.zero_sum_result, &submit); @@ -871,21 +879,26 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) { int overlap_clear = 0, i, disks = sh->disks; struct dma_async_tx_descriptor *tx = NULL; + raid5_conf_t *conf = sh->raid_conf; + struct raid5_percpu *percpu; + unsigned long cpu; + cpu = get_cpu(); + percpu = per_cpu_ptr(conf->percpu, cpu); if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { ops_run_biofill(sh); overlap_clear++; } if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { - tx = ops_run_compute5(sh); + tx = ops_run_compute5(sh, percpu); /* terminate the chain if postxor is not set to be run */ if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request)) async_tx_ack(tx); } if (test_bit(STRIPE_OP_PREXOR, &ops_request)) - tx = ops_run_prexor(sh, tx); + tx = ops_run_prexor(sh, percpu, tx); if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { tx = ops_run_biodrain(sh, tx); @@ -893,10 +906,10 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) } if (test_bit(STRIPE_OP_POSTXOR, &ops_request)) - ops_run_postxor(sh, tx); + ops_run_postxor(sh, percpu, tx); if (test_bit(STRIPE_OP_CHECK, &ops_request)) - ops_run_check(sh); + ops_run_check(sh, percpu); if (overlap_clear) for (i = disks; i--; ) { @@ -904,6 +917,7 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) if (test_and_clear_bit(R5_Overlap, &dev->flags)) wake_up(&sh->raid_conf->wait_for_overlap); } + put_cpu(); } static int grow_one_stripe(raid5_conf_t *conf) @@ -953,6 +967,28 @@ static int grow_stripes(raid5_conf_t *conf, int num) return 0; } +/** + * scribble_len - return the required size of the scribble region + * @num - total number of disks in the array + * + * The size must be enough to contain: + * 1/ a struct page pointer for each device in the array +2 + * 2/ room to convert each entry in (1) to its corresponding dma + * (dma_map_page()) or page (page_address()) address. + * + * Note: the +2 is for the destination buffers of the ddf/raid6 case where we + * calculate over all devices (not just the data blocks), using zeros in place + * of the P and Q blocks. + */ +static size_t scribble_len(int num) +{ + size_t len; + + len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2); + + return len; +} + static int resize_stripes(raid5_conf_t *conf, int newsize) { /* Make all the stripes able to hold 'newsize' devices. @@ -981,6 +1017,7 @@ static int resize_stripes(raid5_conf_t *conf, int newsize) struct stripe_head *osh, *nsh; LIST_HEAD(newstripes); struct disk_info *ndisks; + unsigned long cpu; int err; struct kmem_cache *sc; int i; @@ -1046,7 +1083,7 @@ static int resize_stripes(raid5_conf_t *conf, int newsize) /* Step 3. * At this point, we are holding all the stripes so the array * is completely stalled, so now is a good time to resize - * conf->disks. + * conf->disks and the scribble region */ ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); if (ndisks) { @@ -1057,10 +1094,30 @@ static int resize_stripes(raid5_conf_t *conf, int newsize) } else err = -ENOMEM; + get_online_cpus(); + conf->scribble_len = scribble_len(newsize); + for_each_present_cpu(cpu) { + struct raid5_percpu *percpu; + void *scribble; + + percpu = per_cpu_ptr(conf->percpu, cpu); + scribble = kmalloc(conf->scribble_len, GFP_NOIO); + + if (scribble) { + kfree(percpu->scribble); + percpu->scribble = scribble; + } else { + err = -ENOMEM; + break; + } + } + put_online_cpus(); + /* Step 4, return new stripes to service */ while(!list_empty(&newstripes)) { nsh = list_entry(newstripes.next, struct stripe_head, lru); list_del_init(&nsh->lru); + for (i=conf->raid_disks; i < newsize; i++) if (nsh->dev[i].page == NULL) { struct page *p = alloc_page(GFP_NOIO); @@ -4318,6 +4375,7 @@ static void raid5_free_percpu(raid5_conf_t *conf) for_each_possible_cpu(cpu) { percpu = per_cpu_ptr(conf->percpu, cpu); safe_put_page(percpu->spare_page); + kfree(percpu->scribble); } #ifdef CONFIG_HOTPLUG_CPU unregister_cpu_notifier(&conf->cpu_notify); @@ -4347,9 +4405,15 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action, switch (action) { case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: - if (!percpu->spare_page) + if (conf->level == 6 && !percpu->spare_page) percpu->spare_page = alloc_page(GFP_KERNEL); - if (!percpu->spare_page) { + if (!percpu->scribble) + percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL); + + if (!percpu->scribble || + (conf->level == 6 && !percpu->spare_page)) { + safe_put_page(percpu->spare_page); + kfree(percpu->scribble); pr_err("%s: failed memory allocation for cpu%ld\n", __func__, cpu); return NOTIFY_BAD; @@ -4358,7 +4422,9 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action, case CPU_DEAD: case CPU_DEAD_FROZEN: safe_put_page(percpu->spare_page); + kfree(percpu->scribble); percpu->spare_page = NULL; + percpu->scribble = NULL; break; default: break; @@ -4372,12 +4438,9 @@ static int raid5_alloc_percpu(raid5_conf_t *conf) unsigned long cpu; struct page *spare_page; struct raid5_percpu *allcpus; + void *scribble; int err; - /* the only percpu data is the raid6 spare page */ - if (conf->level != 6) - return 0; - allcpus = alloc_percpu(struct raid5_percpu); if (!allcpus) return -ENOMEM; @@ -4386,12 +4449,20 @@ static int raid5_alloc_percpu(raid5_conf_t *conf) get_online_cpus(); err = 0; for_each_present_cpu(cpu) { - spare_page = alloc_page(GFP_KERNEL); - if (!spare_page) { + if (conf->level == 6) { + spare_page = alloc_page(GFP_KERNEL); + if (!spare_page) { + err = -ENOMEM; + break; + } + per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page; + } + scribble = kmalloc(scribble_len(conf->raid_disks), GFP_KERNEL); + if (!scribble) { err = -ENOMEM; break; } - per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page; + per_cpu_ptr(conf->percpu, cpu)->scribble = scribble; } #ifdef CONFIG_HOTPLUG_CPU conf->cpu_notify.notifier_call = raid456_cpu_notify; @@ -4443,6 +4514,7 @@ static raid5_conf_t *setup_conf(mddev_t *mddev) goto abort; conf->raid_disks = mddev->raid_disks; + conf->scribble_len = scribble_len(conf->raid_disks); if (mddev->reshape_position == MaxSector) conf->previous_raid_disks = mddev->raid_disks; else diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 07a7a4102f05..e7baabffee86 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -386,7 +386,15 @@ struct raid5_private_data { /* per cpu variables */ struct raid5_percpu { struct page *spare_page; /* Used when checking P/Q in raid6 */ + void *scribble; /* space for constructing buffer + * lists and performing address + * conversions + */ } *percpu; + size_t scribble_len; /* size of scribble region must be + * associated with conf to handle + * cpu hotplug while reshaping + */ #ifdef CONFIG_HOTPLUG_CPU struct notifier_block cpu_notify; #endif |