From e61130228ea5740e31e9646ea6d1c9d9089746c3 Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: linear.c: Fix typo in comment. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index b9cbee688fae..61a980da8b51 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -161,7 +161,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) /* min_spacing is the minimum spacing that will fit the hash * table in one PAGE. This may be much smaller than needed. * We find the smallest non-terminal set of consecutive devices - * that is larger than min_spacing as use the size of that as + * that is larger than min_spacing and use the size of that as * the actual spacing */ conf->hash_spacing = conf->array_sectors / 2; -- cgit v1.2.3 From 481d86c7ebe2ce59dfb6ccb720efa9d3fc1cf7cd Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: linear.c: Remove pointless initialization of curr_offset. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 61a980da8b51..632898f3bc98 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -218,7 +218,6 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) conf->disks[i-1].size; table = conf->hash_table; - curr_offset = 0; i = 0; for (curr_offset = 0; curr_offset < conf->array_sectors / 2; -- cgit v1.2.3 From 451708d2a439accbce136637ed4f156fc27371ab Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: linear.c: Remove broken debug code. conf->smallest_size is undefined since day one of the git repo.. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 23 ----------------------- 1 file changed, 23 deletions(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 632898f3bc98..01ed03a0c7ee 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -371,29 +371,6 @@ static int linear_make_request (struct request_queue *q, struct bio *bio) static void linear_status (struct seq_file *seq, mddev_t *mddev) { -#undef MD_DEBUG -#ifdef MD_DEBUG - int j; - linear_conf_t *conf = mddev_to_conf(mddev); - sector_t s = 0; - - seq_printf(seq, " "); - for (j = 0; j < mddev->raid_disks; j++) - { - char b[BDEVNAME_SIZE]; - s += conf->smallest_size; - seq_printf(seq, "[%s", - bdevname(conf->hash_table[j][0].rdev->bdev,b)); - - while (s > conf->hash_table[j][0].offset + - conf->hash_table[j][0].size) - seq_printf(seq, "/%s] ", - bdevname(conf->hash_table[j][1].rdev->bdev,b)); - else - seq_printf(seq, "] "); - } - seq_printf(seq, "\n"); -#endif seq_printf(seq, " %dk rounding", mddev->chunk_size/1024); } -- cgit v1.2.3 From 6283815d1853b7daf31dc4adb83e5c1dc9568251 Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: linear: Represent dev_info->size and dev_info->offset in sectors. Rename them to num_sectors and start_sector which is more descriptive. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 54 ++++++++++++++++++++++++--------------------- include/linux/raid/linear.h | 4 ++-- 2 files changed, 31 insertions(+), 27 deletions(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 01ed03a0c7ee..1dadb134e0bb 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -42,7 +42,7 @@ static inline dev_info_t *which_dev(mddev_t *mddev, sector_t sector) (void)sector_div(block, conf->hash_spacing); hash = conf->hash_table[block]; - while ((sector>>1) >= (hash->size + hash->offset)) + while (sector >= hash->num_sectors + hash->start_sector) hash++; return hash; } @@ -65,7 +65,7 @@ static int linear_mergeable_bvec(struct request_queue *q, sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); dev0 = which_dev(mddev, sector); - maxsectors = (dev0->size << 1) - (sector - (dev0->offset<<1)); + maxsectors = dev0->num_sectors - (sector - dev0->start_sector); if (maxsectors < bio_sectors) maxsectors = 0; @@ -113,7 +113,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) mdk_rdev_t *rdev; int i, nb_zone, cnt; sector_t min_spacing; - sector_t curr_offset; + sector_t curr_sector; struct list_head *tmp; conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(dev_info_t), @@ -145,7 +145,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) mddev->queue->max_sectors > (PAGE_SIZE>>9)) blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); - disk->size = rdev->size; + disk->num_sectors = rdev->size * 2; conf->array_sectors += rdev->size * 2; cnt++; @@ -169,7 +169,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) sector_t sz = 0; int j; for (j = i; j < cnt - 1 && sz < min_spacing; j++) - sz += conf->disks[j].size; + sz += conf->disks[j].num_sectors / 2; if (sz >= min_spacing && sz < conf->hash_spacing) conf->hash_spacing = sz; } @@ -211,20 +211,20 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) * Here we generate the linear hash table * First calculate the device offsets. */ - conf->disks[0].offset = 0; + conf->disks[0].start_sector = 0; for (i = 1; i < raid_disks; i++) - conf->disks[i].offset = - conf->disks[i-1].offset + - conf->disks[i-1].size; + conf->disks[i].start_sector = + conf->disks[i-1].start_sector + + conf->disks[i-1].num_sectors; table = conf->hash_table; i = 0; - for (curr_offset = 0; - curr_offset < conf->array_sectors / 2; - curr_offset += conf->hash_spacing) { + for (curr_sector = 0; + curr_sector < conf->array_sectors; + curr_sector += conf->hash_spacing * 2) { while (i < raid_disks-1 && - curr_offset >= conf->disks[i+1].offset) + curr_sector >= conf->disks[i+1].start_sector) i++; *table ++ = conf->disks + i; @@ -316,7 +316,6 @@ static int linear_make_request (struct request_queue *q, struct bio *bio) const int rw = bio_data_dir(bio); mddev_t *mddev = q->queuedata; dev_info_t *tmp_dev; - sector_t block; int cpu; if (unlikely(bio_barrier(bio))) { @@ -331,29 +330,33 @@ static int linear_make_request (struct request_queue *q, struct bio *bio) part_stat_unlock(); tmp_dev = which_dev(mddev, bio->bi_sector); - block = bio->bi_sector >> 1; - if (unlikely(block >= (tmp_dev->size + tmp_dev->offset) - || block < tmp_dev->offset)) { + if (unlikely(bio->bi_sector >= (tmp_dev->num_sectors + + tmp_dev->start_sector) + || (bio->bi_sector < + tmp_dev->start_sector))) { char b[BDEVNAME_SIZE]; - printk("linear_make_request: Block %llu out of bounds on " - "dev %s size %llu offset %llu\n", - (unsigned long long)block, + printk("linear_make_request: Sector %llu out of bounds on " + "dev %s: %llu sectors, offset %llu\n", + (unsigned long long)bio->bi_sector, bdevname(tmp_dev->rdev->bdev, b), - (unsigned long long)tmp_dev->size, - (unsigned long long)tmp_dev->offset); + (unsigned long long)tmp_dev->num_sectors, + (unsigned long long)tmp_dev->start_sector); bio_io_error(bio); return 0; } if (unlikely(bio->bi_sector + (bio->bi_size >> 9) > - (tmp_dev->offset + tmp_dev->size)<<1)) { + tmp_dev->start_sector + tmp_dev->num_sectors)) { /* This bio crosses a device boundary, so we have to * split it. */ struct bio_pair *bp; + bp = bio_split(bio, - ((tmp_dev->offset + tmp_dev->size)<<1) - bio->bi_sector); + tmp_dev->start_sector + tmp_dev->num_sectors + - bio->bi_sector); + if (linear_make_request(q, &bp->bio1)) generic_make_request(&bp->bio1); if (linear_make_request(q, &bp->bio2)) @@ -363,7 +366,8 @@ static int linear_make_request (struct request_queue *q, struct bio *bio) } bio->bi_bdev = tmp_dev->rdev->bdev; - bio->bi_sector = bio->bi_sector - (tmp_dev->offset << 1) + tmp_dev->rdev->data_offset; + bio->bi_sector = bio->bi_sector - tmp_dev->start_sector + + tmp_dev->rdev->data_offset; return 1; } diff --git a/include/linux/raid/linear.h b/include/linux/raid/linear.h index 7e375111d007..87090e98529f 100644 --- a/include/linux/raid/linear.h +++ b/include/linux/raid/linear.h @@ -5,8 +5,8 @@ struct dev_info { mdk_rdev_t *rdev; - sector_t size; - sector_t offset; + sector_t num_sectors; + sector_t start_sector; }; typedef struct dev_info dev_info_t; -- cgit v1.2.3 From 23242fbb470ff4c8c4d41f178832cf1929273d7d Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: linear.c: Make two local variables sector-based. This is a preparation for representing also the remaining fields of struct linear_private_data as sectors. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 1dadb134e0bb..13e928bde7cd 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -112,7 +112,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) dev_info_t **table; mdk_rdev_t *rdev; int i, nb_zone, cnt; - sector_t min_spacing; + sector_t min_sectors; sector_t curr_sector; struct list_head *tmp; @@ -155,23 +155,23 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) goto out; } - min_spacing = conf->array_sectors / 2; - sector_div(min_spacing, PAGE_SIZE/sizeof(struct dev_info *)); + min_sectors = conf->array_sectors; + sector_div(min_sectors, PAGE_SIZE/sizeof(struct dev_info *)); - /* min_spacing is the minimum spacing that will fit the hash + /* min_sectors is the minimum spacing that will fit the hash * table in one PAGE. This may be much smaller than needed. * We find the smallest non-terminal set of consecutive devices - * that is larger than min_spacing and use the size of that as + * that is larger than min_sectors and use the size of that as * the actual spacing */ conf->hash_spacing = conf->array_sectors / 2; for (i=0; i < cnt-1 ; i++) { - sector_t sz = 0; + sector_t tmp = 0; int j; - for (j = i; j < cnt - 1 && sz < min_spacing; j++) - sz += conf->disks[j].num_sectors / 2; - if (sz >= min_spacing && sz < conf->hash_spacing) - conf->hash_spacing = sz; + for (j = i; j < cnt - 1 && tmp < min_sectors; j++) + tmp += conf->disks[j].num_sectors; + if (tmp >= min_sectors && tmp < conf->hash_spacing * 2) + conf->hash_spacing = tmp / 2; } /* hash_spacing may be too large for sector_div to work with, -- cgit v1.2.3 From ab5bd5cbc8d4b868378d062eed3d4240930fbb86 Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: Convert remaining 1k representations in linear.c to sectors. This patch renames hash_spacing and preshift to spacing and sector_shift respectively with the following change of semantics: Case 1: (sizeof(sector_t) <= sizeof(u32)). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In this case, we have sector_shift = preshift = 0 and spacing = 2 * hash_spacing. Hence, the index for the hash table which is computed by the new code in which_dev() as sector / spacing equals the old value which was (sector/2) / hash_spacing. Note also that the value of nb_zone stays the same because both sz and base double. Case 2: (sizeof(sector_t) > sizeof(u32)). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (aka the shifting dance case). Here we have sector_shift = preshift + 1 and spacing = 2 * hash_spacing during the computation of nb_zone and curr_sector, but spacing = hash_spacing in which_dev() because in the last hunk of the patch for linear.c we shift down conf->spacing (= 2 * hash_spacing) by one more bit than in the old code. Hence in the computation of nb_zone, sz and base have the same value as before, so nb_zone is not affected. Also curr_sector in the next hunk stays the same. In which_dev() the hash table index is computed as (sector >> sector_shift) / spacing In view of sector_shift = preshift + 1 and spacing = hash_spacing, this equals ((sector/2) >> preshift) / hash_spacing which is the value computed by the old code. Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 35 +++++++++++++++++------------------ include/linux/raid/linear.h | 6 ++++-- 2 files changed, 21 insertions(+), 20 deletions(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 13e928bde7cd..09a64b9cbde8 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -33,14 +33,13 @@ static inline dev_info_t *which_dev(mddev_t *mddev, sector_t sector) { dev_info_t *hash; linear_conf_t *conf = mddev_to_conf(mddev); - sector_t block = sector >> 1; /* * sector_div(a,b) returns the remainer and sets a to a/b */ - block >>= conf->preshift; - (void)sector_div(block, conf->hash_spacing); - hash = conf->hash_table[block]; + sector >>= conf->sector_shift; + (void)sector_div(sector, conf->spacing); + hash = conf->hash_table[sector]; while (sector >= hash->num_sectors + hash->start_sector) hash++; @@ -164,25 +163,25 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) * that is larger than min_sectors and use the size of that as * the actual spacing */ - conf->hash_spacing = conf->array_sectors / 2; + conf->spacing = conf->array_sectors; for (i=0; i < cnt-1 ; i++) { sector_t tmp = 0; int j; for (j = i; j < cnt - 1 && tmp < min_sectors; j++) tmp += conf->disks[j].num_sectors; - if (tmp >= min_sectors && tmp < conf->hash_spacing * 2) - conf->hash_spacing = tmp / 2; + if (tmp >= min_sectors && tmp < conf->spacing) + conf->spacing = tmp; } - /* hash_spacing may be too large for sector_div to work with, + /* spacing may be too large for sector_div to work with, * so we might need to pre-shift */ - conf->preshift = 0; + conf->sector_shift = 0; if (sizeof(sector_t) > sizeof(u32)) { - sector_t space = conf->hash_spacing; + sector_t space = conf->spacing; while (space > (sector_t)(~(u32)0)) { space >>= 1; - conf->preshift++; + conf->sector_shift++; } } /* @@ -194,9 +193,9 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) unsigned round; unsigned long base; - sz = conf->array_sectors >> (conf->preshift + 1); + sz = conf->array_sectors >> conf->sector_shift; sz += 1; /* force round-up */ - base = conf->hash_spacing >> conf->preshift; + base = conf->spacing >> conf->sector_shift; round = sector_div(sz, base); nb_zone = sz + (round ? 1 : 0); } @@ -221,7 +220,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) i = 0; for (curr_sector = 0; curr_sector < conf->array_sectors; - curr_sector += conf->hash_spacing * 2) { + curr_sector += conf->spacing) { while (i < raid_disks-1 && curr_sector >= conf->disks[i+1].start_sector) @@ -230,12 +229,12 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) *table ++ = conf->disks + i; } - if (conf->preshift) { - conf->hash_spacing >>= conf->preshift; - /* round hash_spacing up so that when we divide by it, + if (conf->sector_shift) { + conf->spacing >>= conf->sector_shift; + /* round spacing up so that when we divide by it, * we err on the side of "too-low", which is safest. */ - conf->hash_spacing++; + conf->spacing++; } BUG_ON(table - conf->hash_table > nb_zone); diff --git a/include/linux/raid/linear.h b/include/linux/raid/linear.h index 87090e98529f..f38b9c586afb 100644 --- a/include/linux/raid/linear.h +++ b/include/linux/raid/linear.h @@ -15,9 +15,11 @@ struct linear_private_data { struct linear_private_data *prev; /* earlier version */ dev_info_t **hash_table; - sector_t hash_spacing; + sector_t spacing; sector_t array_sectors; - int preshift; /* shift before dividing by hash_spacing */ + int sector_shift; /* shift before dividing + * by spacing + */ dev_info_t disks[0]; }; -- cgit v1.2.3 From fb4d8c76e56a887b9eee99fbc55fe82b18625d30 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 13 Oct 2008 11:55:12 +1100 Subject: md: Remove unnecessary #includes, #defines, and function declarations. A lot of cruft has gathered over the years. Time to remove it. Signed-off-by: NeilBrown --- drivers/md/linear.c | 8 -------- drivers/md/md.c | 21 ++++----------------- drivers/md/multipath.c | 9 --------- drivers/md/raid0.c | 5 ----- drivers/md/raid5.c | 5 ----- drivers/md/raid6.h | 9 --------- include/linux/raid/md.h | 22 ---------------------- 7 files changed, 4 insertions(+), 75 deletions(-) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 09a64b9cbde8..190147c79e79 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -16,16 +16,8 @@ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include - -#include -#include #include -#define MAJOR_NR MD_MAJOR -#define MD_DRIVER -#define MD_PERSONALITY - /* * find which device holds a particular offset */ diff --git a/drivers/md/md.c b/drivers/md/md.c index fc33082d5ffd..cd97de5982e8 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -32,31 +32,20 @@ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include -#include #include -#include #include #include #include #include /* for invalidate_bdev */ #include -#include #include -#include - -#include - +#include +#include +#include +#include #include -#ifdef CONFIG_KMOD -#include -#endif - -#include - #define MAJOR_NR MD_MAJOR -#define MD_DRIVER /* 63 partitions with the alternate major number (mdp) */ #define MdpMinorShift 6 @@ -3559,12 +3548,10 @@ static int do_md_run(mddev_t * mddev) } } -#ifdef CONFIG_KMOD if (mddev->level != LEVEL_NONE) request_module("md-level-%d", mddev->level); else if (mddev->clevel[0]) request_module("md-%s", mddev->clevel); -#endif /* * Drop all container device buffers, from now on diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c index 8bb8794129b3..8744014b9d80 100644 --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -19,16 +19,7 @@ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include -#include -#include #include -#include -#include - -#define MAJOR_NR MD_MAJOR -#define MD_DRIVER -#define MD_PERSONALITY #define MAX_WORK_PER_DISK 128 diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 53508a8a981d..8ac6488ad0dc 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -18,13 +18,8 @@ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include #include -#define MAJOR_NR MD_MAJOR -#define MD_DRIVER -#define MD_PERSONALITY - static void raid0_unplug(struct request_queue *q) { mddev_t *mddev = q->queuedata; diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index ae16794bef20..7e654543c97d 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -43,12 +43,7 @@ * miss any bits. */ -#include -#include -#include -#include #include -#include #include "raid6.h" #include diff --git a/drivers/md/raid6.h b/drivers/md/raid6.h index 31cbee71365f..98dcde88470e 100644 --- a/drivers/md/raid6.h +++ b/drivers/md/raid6.h @@ -18,15 +18,6 @@ /* Set to 1 to use kernel-wide empty_zero_page */ #define RAID6_USE_EMPTY_ZERO_PAGE 0 -#include -#include -#include -#include -#include -#include -#include -#include -#include #include #include diff --git a/include/linux/raid/md.h b/include/linux/raid/md.h index dc0e3fcb9f28..bb727fa1ce7f 100644 --- a/include/linux/raid/md.h +++ b/include/linux/raid/md.h @@ -19,27 +19,7 @@ #define _MD_H #include -#include -#include -#include -#include -#include -#include -#include #include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include /* * 'md_p.h' holds the 'physical' layout of RAID devices @@ -83,10 +63,8 @@ extern void md_wakeup_thread(mdk_thread_t *thread); extern void md_check_recovery(mddev_t *mddev); extern void md_write_start(mddev_t *mddev, struct bio *bi); extern void md_write_end(mddev_t *mddev); -extern void md_handle_safemode(mddev_t *mddev); extern void md_done_sync(mddev_t *mddev, int blocks, int ok); extern void md_error (mddev_t *mddev, mdk_rdev_t *rdev); -extern void md_unplug_mddev(mddev_t *mddev); extern void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, sector_t sector, int size, struct page *page); -- cgit v1.2.3 From f1cd14ae52985634d0389e934eba25b5ecf24565 Mon Sep 17 00:00:00 2001 From: Andre Noll Date: Thu, 6 Nov 2008 19:41:24 +1100 Subject: md: linear: Fix a division by zero bug for very small arrays. We currently oops with a divide error on starting a linear software raid array consisting of at least two very small (< 500K) devices. The bug is caused by the calculation of the hash table size which tries to compute sector_div(sz, base) with "base" being zero due to the small size of the component devices of the array. Fix this by requiring the hash spacing to be at least one which implies that also "base" is non-zero. This bug has existed since about 2.6.14. Cc: stable@kernel.org Signed-off-by: Andre Noll Signed-off-by: NeilBrown --- drivers/md/linear.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/md/linear.c') diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 190147c79e79..3b90c5c924ec 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -148,6 +148,8 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) min_sectors = conf->array_sectors; sector_div(min_sectors, PAGE_SIZE/sizeof(struct dev_info *)); + if (min_sectors == 0) + min_sectors = 1; /* min_sectors is the minimum spacing that will fit the hash * table in one PAGE. This may be much smaller than needed. -- cgit v1.2.3