Merge branch 'for-next' of git://neil.brown.name/md

Pull md updates from NeilBrown.

* 'for-next' of git://neil.brown.name/md:
  DM RAID: Add support for MD RAID10
  md/RAID1: Add missing case for attempting to repair known bad blocks.
  md/raid5: For odirect-write performance, do not set STRIPE_PREREAD_ACTIVE.
  md/raid1: don't abort a resync on the first badblock.
  md: remove duplicated test on ->openers when calling do_md_stop()
  raid5: Add R5_ReadNoMerge flag which prevent bio from merging at block layer
  md/raid1: prevent merging too large request
  md/raid1: read balance chooses idlest disk for SSD
  md/raid1: make sequential read detection per disk based
  MD RAID10: Export md_raid10_congested
  MD: Move macros from raid1*.h to raid1*.c
  MD RAID1: rename mirror_info structure
  MD RAID10: rename mirror_info structure
  MD RAID10: Fix compiler warning.
  raid5: add a per-stripe lock
  raid5: remove unnecessary bitmap write optimization
  raid5: lockless access raid5 overrided bi_phys_segments
  raid5: reduce chance release_stripe() taking device_lock

diff --combined drivers/md/dm-raid.c
index f2f29c52654480314c1219e3524a7239821384c4,691b3c59088e1a479ff26a22f2cb51eacb813160..982e3e390c458ceadeab3b5f9618cf4e1bb5891e
--- 1/drivers/md/dm-raid.c
--- 2/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@@ -11,6 -11,7 +11,7 @@@
  #include "md.h"
  #include "raid1.h"
  #include "raid5.h"
+ #include "raid10.h"
  #include "bitmap.h"
  
  #include <linux/device-mapper.h>
@@@ -52,7 -53,10 +53,10 @@@ struct raid_dev 
  #define DMPF_MAX_RECOVERY_RATE 0x20
  #define DMPF_MAX_WRITE_BEHIND  0x40
  #define DMPF_STRIPE_CACHE      0x80
- #define DMPF_REGION_SIZE       0X100
+ #define DMPF_REGION_SIZE       0x100
+ #define DMPF_RAID10_COPIES     0x200
+ #define DMPF_RAID10_FORMAT     0x400
+ 
  struct raid_set {
        struct dm_target *ti;
  
@@@ -76,6 -80,7 +80,7 @@@ static struct raid_type 
        const unsigned algorithm;       /* RAID algorithm. */
  } raid_types[] = {
        {"raid1",    "RAID1 (mirroring)",               0, 2, 1, 0 /* NONE */},
+       {"raid10",   "RAID10 (striped mirrors)",        0, 2, 10, UINT_MAX /* Varies */},
        {"raid4",    "RAID4 (dedicated parity disk)",   1, 2, 5, ALGORITHM_PARITY_0},
        {"raid5_la", "RAID5 (left asymmetric)",         1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
        {"raid5_ra", "RAID5 (right asymmetric)",        1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
@@@ -86,6 -91,17 +91,17 @@@
        {"raid6_nc", "RAID6 (N continue)",              2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE}
  };
  
+ static unsigned raid10_md_layout_to_copies(int layout)
+ {
+       return layout & 0xFF;
+ }
+ 
+ static int raid10_format_to_md_layout(char *format, unsigned copies)
+ {
+       /* 1 "far" copy, and 'copies' "near" copies */
+       return (1 << 8) | (copies & 0xFF);
+ }
+ 
  static struct raid_type *get_raid_type(char *name)
  {
        int i;
@@@ -339,10 -355,16 +355,16 @@@ static int validate_region_size(struct 
   *    [max_write_behind <sectors>]    See '-write-behind=' (man mdadm)
   *    [stripe_cache <sectors>]                Stripe cache size for higher RAIDs
   *    [region_size <sectors>]           Defines granularity of bitmap
+  *
+  * RAID10-only options:
+  *    [raid10_copies <# copies>]        Number of copies.  (Default: 2)
+  *    [raid10_format <near>]            Layout algorithm.  (Default: near)
   */
  static int parse_raid_params(struct raid_set *rs, char **argv,
                             unsigned num_raid_params)
  {
+       char *raid10_format = "near";
+       unsigned raid10_copies = 2;
        unsigned i, rebuild_cnt = 0;
        unsigned long value, region_size = 0;
        sector_t sectors_per_dev = rs->ti->len;
@@@ -416,11 -438,28 +438,28 @@@
                }
  
                key = argv[i++];
+ 
+               /* Parameters that take a string value are checked here. */
+               if (!strcasecmp(key, "raid10_format")) {
+                       if (rs->raid_type->level != 10) {
+                               rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
+                               return -EINVAL;
+                       }
+                       if (strcmp("near", argv[i])) {
+                               rs->ti->error = "Invalid 'raid10_format' value given";
+                               return -EINVAL;
+                       }
+                       raid10_format = argv[i];
+                       rs->print_flags |= DMPF_RAID10_FORMAT;
+                       continue;
+               }
+ 
                if (strict_strtoul(argv[i], 10, &value) < 0) {
                        rs->ti->error = "Bad numerical argument given in raid params";
                        return -EINVAL;
                }
  
+               /* Parameters that take a numeric value are checked here */
                if (!strcasecmp(key, "rebuild")) {
                        rebuild_cnt++;
  
@@@ -439,6 -478,7 +478,7 @@@
                                        return -EINVAL;
                                }
                                break;
+                       case 10:
                        default:
                                DMERR("The rebuild parameter is not supported for %s", rs->raid_type->name);
                                rs->ti->error = "Rebuild not supported for this RAID type";
@@@ -495,7 -535,8 +535,8 @@@
                         */
                        value /= 2;
  
-                       if (rs->raid_type->level < 5) {
+                       if ((rs->raid_type->level != 5) &&
+                           (rs->raid_type->level != 6)) {
                                rs->ti->error = "Inappropriate argument: stripe_cache";
                                return -EINVAL;
                        }
@@@ -520,6 -561,14 +561,14 @@@
                } else if (!strcasecmp(key, "region_size")) {
                        rs->print_flags |= DMPF_REGION_SIZE;
                        region_size = value;
+               } else if (!strcasecmp(key, "raid10_copies") &&
+                          (rs->raid_type->level == 10)) {
+                       if ((value < 2) || (value > 0xFF)) {
+                               rs->ti->error = "Bad value for 'raid10_copies'";
+                               return -EINVAL;
+                       }
+                       rs->print_flags |= DMPF_RAID10_COPIES;
+                       raid10_copies = value;
                } else {
                        DMERR("Unable to parse RAID parameter: %s", key);
                        rs->ti->error = "Unable to parse RAID parameters";
@@@ -538,8 -587,22 +587,22 @@@
        if (dm_set_target_max_io_len(rs->ti, max_io_len))
                return -EINVAL;
  
-       if ((rs->raid_type->level > 1) &&
-           sector_div(sectors_per_dev, (rs->md.raid_disks - rs->raid_type->parity_devs))) {
+       if (rs->raid_type->level == 10) {
+               if (raid10_copies > rs->md.raid_disks) {
+                       rs->ti->error = "Not enough devices to satisfy specification";
+                       return -EINVAL;
+               }
+ 
+               /* (Len * #mirrors) / #devices */
+               sectors_per_dev = rs->ti->len * raid10_copies;
+               sector_div(sectors_per_dev, rs->md.raid_disks);
+ 
+               rs->md.layout = raid10_format_to_md_layout(raid10_format,
+                                                          raid10_copies);
+               rs->md.new_layout = rs->md.layout;
+       } else if ((rs->raid_type->level > 1) &&
+                  sector_div(sectors_per_dev,
+                             (rs->md.raid_disks - rs->raid_type->parity_devs))) {
                rs->ti->error = "Target length not divisible by number of data devices";
                return -EINVAL;
        }
@@@ -566,6 -629,9 +629,9 @@@ static int raid_is_congested(struct dm_
        if (rs->raid_type->level == 1)
                return md_raid1_congested(&rs->md, bits);
  
+       if (rs->raid_type->level == 10)
+               return md_raid10_congested(&rs->md, bits);
+ 
        return md_raid5_congested(&rs->md, bits);
  }
  
@@@ -884,6 -950,9 +950,9 @@@ static int analyse_superblocks(struct d
        case 6:
                redundancy = rs->raid_type->parity_devs;
                break;
+       case 10:
+               redundancy = raid10_md_layout_to_copies(mddev->layout) - 1;
+               break;
        default:
                ti->error = "Unknown RAID type";
                return -EINVAL;
@@@ -1049,12 -1118,19 +1118,19 @@@ static int raid_ctr(struct dm_target *t
                goto bad;
        }
  
+       if (ti->len != rs->md.array_sectors) {
+               ti->error = "Array size does not match requested target length";
+               ret = -EINVAL;
+               goto size_mismatch;
+       }
        rs->callbacks.congested_fn = raid_is_congested;
        dm_table_add_target_callbacks(ti->table, &rs->callbacks);
  
        mddev_suspend(&rs->md);
        return 0;
  
+ size_mismatch:
+       md_stop(&rs->md);
  bad:
        context_free(rs);
  
@@@ -1081,7 -1157,7 +1157,7 @@@ static int raid_map(struct dm_target *t
  }
  
  static int raid_status(struct dm_target *ti, status_type_t type,
 -                     char *result, unsigned maxlen)
 +                     unsigned status_flags, char *result, unsigned maxlen)
  {
        struct raid_set *rs = ti->private;
        unsigned raid_param_cnt = 1; /* at least 1 for chunksize */
@@@ -1203,6 -1279,13 +1279,13 @@@
                        DMEMIT(" region_size %lu",
                               rs->md.bitmap_info.chunksize >> 9);
  
+               if (rs->print_flags & DMPF_RAID10_COPIES)
+                       DMEMIT(" raid10_copies %u",
+                              raid10_md_layout_to_copies(rs->md.layout));
+ 
+               if (rs->print_flags & DMPF_RAID10_FORMAT)
+                       DMEMIT(" raid10_format near");
+ 
                DMEMIT(" %d", rs->md.raid_disks);
                for (i = 0; i < rs->md.raid_disks; i++) {
                        if (rs->dev[i].meta_dev)
@@@ -1277,7 -1360,7 +1360,7 @@@ static void raid_resume(struct dm_targe
  
  static struct target_type raid_target = {
        .name = "raid",
-       .version = {1, 2, 0},
+       .version = {1, 3, 0},
        .module = THIS_MODULE,
        .ctr = raid_ctr,
        .dtr = raid_dtr,
@@@ -1304,6 -1387,8 +1387,8 @@@ module_init(dm_raid_init)
  module_exit(dm_raid_exit);
  
  MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target");
+ MODULE_ALIAS("dm-raid1");
+ MODULE_ALIAS("dm-raid10");
  MODULE_ALIAS("dm-raid4");
  MODULE_ALIAS("dm-raid5");
  MODULE_ALIAS("dm-raid6");