]> err.no Git - linux-2.6/blobdiff - drivers/md/md.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild
[linux-2.6] / drivers / md / md.c
index 2b4315d7e5d6531573e7ecfedd425df19178a3f3..65ddc887dfd72dc97a2ace8bb4c8bbf93c8e5f94 100644 (file)
@@ -33,6 +33,7 @@
 */
 
 #include <linux/module.h>
+#include <linux/kernel.h>
 #include <linux/kthread.h>
 #include <linux/linkage.h>
 #include <linux/raid/md.h>
@@ -273,6 +274,7 @@ static mddev_t * mddev_find(dev_t unit)
        atomic_set(&new->active, 1);
        spin_lock_init(&new->write_lock);
        init_waitqueue_head(&new->sb_wait);
+       new->reshape_position = MaxSector;
 
        new->queue = blk_alloc_queue(GFP_KERNEL);
        if (!new->queue) {
@@ -589,14 +591,41 @@ abort:
        return ret;
 }
 
+
+static u32 md_csum_fold(u32 csum)
+{
+       csum = (csum & 0xffff) + (csum >> 16);
+       return (csum & 0xffff) + (csum >> 16);
+}
+
 static unsigned int calc_sb_csum(mdp_super_t * sb)
 {
+       u64 newcsum = 0;
+       u32 *sb32 = (u32*)sb;
+       int i;
        unsigned int disk_csum, csum;
 
        disk_csum = sb->sb_csum;
        sb->sb_csum = 0;
-       csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
+
+       for (i = 0; i < MD_SB_BYTES/4 ; i++)
+               newcsum += sb32[i];
+       csum = (newcsum & 0xffffffff) + (newcsum>>32);
+
+
+#ifdef CONFIG_ALPHA
+       /* This used to use csum_partial, which was wrong for several
+        * reasons including that different results are returned on
+        * different architectures.  It isn't critical that we get exactly
+        * the same return value as before (we always csum_fold before
+        * testing, and that removes any differences).  However as we
+        * know that csum_partial always returned a 16bit value on
+        * alphas, do a fold to maximise conformity to previous behaviour.
+        */
+       sb->sb_csum = md_csum_fold(disk_csum);
+#else
        sb->sb_csum = disk_csum;
+#endif
        return csum;
 }
 
@@ -684,7 +713,7 @@ static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version
        if (sb->raid_disks <= 0)
                goto abort;
 
-       if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
+       if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
                printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
                        b);
                goto abort;
@@ -694,6 +723,17 @@ static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version
        rdev->data_offset = 0;
        rdev->sb_size = MD_SB_BYTES;
 
+       if (sb->state & (1<<MD_SB_BITMAP_PRESENT)) {
+               if (sb->level != 1 && sb->level != 4
+                   && sb->level != 5 && sb->level != 6
+                   && sb->level != 10) {
+                       /* FIXME use a better test */
+                       printk(KERN_WARNING
+                              "md: bitmaps not supported for this level.\n");
+                       goto abort;
+               }
+       }
+
        if (sb->level == LEVEL_MULTIPATH)
                rdev->desc_nr = -1;
        else
@@ -792,16 +832,8 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                mddev->max_disks = MD_SB_DISKS;
 
                if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
-                   mddev->bitmap_file == NULL) {
-                       if (mddev->level != 1 && mddev->level != 4
-                           && mddev->level != 5 && mddev->level != 6
-                           && mddev->level != 10) {
-                               /* FIXME use a better test */
-                               printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
-                               return -EINVAL;
-                       }
+                   mddev->bitmap_file == NULL)
                        mddev->bitmap_offset = mddev->default_bitmap_offset;
-               }
 
        } else if (mddev->pers == NULL) {
                /* Insist on good event counter while assembling */
@@ -1058,6 +1090,18 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
                       bdevname(rdev->bdev,b));
                return -EINVAL;
        }
+       if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET)) {
+               if (sb->level != cpu_to_le32(1) &&
+                   sb->level != cpu_to_le32(4) &&
+                   sb->level != cpu_to_le32(5) &&
+                   sb->level != cpu_to_le32(6) &&
+                   sb->level != cpu_to_le32(10)) {
+                       printk(KERN_WARNING
+                              "md: bitmaps not supported for this level.\n");
+                       return -EINVAL;
+               }
+       }
+
        rdev->preferred_minor = 0xffff;
        rdev->data_offset = le64_to_cpu(sb->data_offset);
        atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
@@ -1141,14 +1185,9 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                mddev->max_disks =  (4096-256)/2;
 
                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
-                   mddev->bitmap_file == NULL ) {
-                       if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
-                           && mddev->level != 10) {
-                               printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
-                               return -EINVAL;
-                       }
+                   mddev->bitmap_file == NULL )
                        mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
-               }
+
                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
                        mddev->reshape_position = le64_to_cpu(sb->reshape_position);
                        mddev->delta_disks = le32_to_cpu(sb->delta_disks);
@@ -1259,8 +1298,9 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
        ITERATE_RDEV(mddev,rdev2,tmp)
                if (rdev2->desc_nr+1 > max_dev)
                        max_dev = rdev2->desc_nr+1;
-       
-       sb->max_dev = cpu_to_le32(max_dev);
+
+       if (max_dev > le32_to_cpu(sb->max_dev))
+               sb->max_dev = cpu_to_le32(max_dev);
        for (i=0; i<max_dev;i++)
                sb->dev_roles[i] = cpu_to_le16(0xfffe);
        
@@ -1326,10 +1366,14 @@ static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
        }
        /* make sure rdev->size exceeds mddev->size */
        if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
-               if (mddev->pers)
-                       /* Cannot change size, so fail */
-                       return -ENOSPC;
-               else
+               if (mddev->pers) {
+                       /* Cannot change size, so fail
+                        * If mddev->level <= 0, then we don't care
+                        * about aligning sizes (e.g. linear)
+                        */
+                       if (mddev->level > 0)
+                               return -ENOSPC;
+               } else
                        mddev->size = rdev->size;
        }
 
@@ -1596,7 +1640,6 @@ static void sync_sbs(mddev_t * mddev, int nospares)
 
 static void md_update_sb(mddev_t * mddev, int force_change)
 {
-       int err;
        struct list_head *tmp;
        mdk_rdev_t *rdev;
        int sync_req;
@@ -1683,7 +1726,7 @@ repeat:
                "md: updating %s RAID superblock on device (in sync %d)\n",
                mdname(mddev),mddev->in_sync);
 
-       err = bitmap_update_sb(mddev->bitmap);
+       bitmap_update_sb(mddev->bitmap);
        ITERATE_RDEV(mddev,rdev,tmp) {
                char b[BDEVNAME_SIZE];
                dprintk(KERN_INFO "md: ");
@@ -2029,9 +2072,11 @@ static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_mi
                err = super_types[super_format].
                        load_super(rdev, NULL, super_minor);
                if (err == -EINVAL) {
-                       printk(KERN_WARNING 
-                               "md: %s has invalid sb, not importing!\n",
-                               bdevname(rdev->bdev,b));
+                       printk(KERN_WARNING
+                               "md: %s does not have a valid v%d.%d "
+                              "superblock, not importing!\n",
+                               bdevname(rdev->bdev,b),
+                              super_format, super_minor);
                        goto abort_free;
                }
                if (err < 0) {
@@ -2103,6 +2148,9 @@ static void analyze_sbs(mddev_t * mddev)
                        rdev->desc_nr = i++;
                        rdev->raid_disk = rdev->desc_nr;
                        set_bit(In_sync, &rdev->flags);
+               } else if (rdev->raid_disk >= mddev->raid_disks) {
+                       rdev->raid_disk = -1;
+                       clear_bit(In_sync, &rdev->flags);
                }
        }
 
@@ -2204,6 +2252,10 @@ static ssize_t
 layout_show(mddev_t *mddev, char *page)
 {
        /* just a number, not meaningful for all levels */
+       if (mddev->reshape_position != MaxSector &&
+           mddev->layout != mddev->new_layout)
+               return sprintf(page, "%d (%d)\n",
+                              mddev->new_layout, mddev->layout);
        return sprintf(page, "%d\n", mddev->layout);
 }
 
@@ -2212,13 +2264,16 @@ layout_store(mddev_t *mddev, const char *buf, size_t len)
 {
        char *e;
        unsigned long n = simple_strtoul(buf, &e, 10);
-       if (mddev->pers)
-               return -EBUSY;
 
        if (!*buf || (*e && *e != '\n'))
                return -EINVAL;
 
-       mddev->layout = n;
+       if (mddev->pers)
+               return -EBUSY;
+       if (mddev->reshape_position != MaxSector)
+               mddev->new_layout = n;
+       else
+               mddev->layout = n;
        return len;
 }
 static struct md_sysfs_entry md_layout =
@@ -2230,6 +2285,10 @@ raid_disks_show(mddev_t *mddev, char *page)
 {
        if (mddev->raid_disks == 0)
                return 0;
+       if (mddev->reshape_position != MaxSector &&
+           mddev->delta_disks != 0)
+               return sprintf(page, "%d (%d)\n", mddev->raid_disks,
+                              mddev->raid_disks - mddev->delta_disks);
        return sprintf(page, "%d\n", mddev->raid_disks);
 }
 
@@ -2247,7 +2306,11 @@ raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
 
        if (mddev->pers)
                rv = update_raid_disks(mddev, n);
-       else
+       else if (mddev->reshape_position != MaxSector) {
+               int olddisks = mddev->raid_disks - mddev->delta_disks;
+               mddev->delta_disks = n - olddisks;
+               mddev->raid_disks = n;
+       } else
                mddev->raid_disks = n;
        return rv ? rv : len;
 }
@@ -2257,6 +2320,10 @@ __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
 static ssize_t
 chunk_size_show(mddev_t *mddev, char *page)
 {
+       if (mddev->reshape_position != MaxSector &&
+           mddev->chunk_size != mddev->new_chunk)
+               return sprintf(page, "%d (%d)\n", mddev->new_chunk,
+                              mddev->chunk_size);
        return sprintf(page, "%d\n", mddev->chunk_size);
 }
 
@@ -2267,12 +2334,15 @@ chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
        char *e;
        unsigned long n = simple_strtoul(buf, &e, 10);
 
-       if (mddev->pers)
-               return -EBUSY;
        if (!*buf || (*e && *e != '\n'))
                return -EINVAL;
 
-       mddev->chunk_size = n;
+       if (mddev->pers)
+               return -EBUSY;
+       else if (mddev->reshape_position != MaxSector)
+               mddev->new_chunk = n;
+       else
+               mddev->chunk_size = n;
        return len;
 }
 static struct md_sysfs_entry md_chunk_size =
@@ -2637,8 +2707,7 @@ metadata_store(mddev_t *mddev, const char *buf, size_t len)
        minor = simple_strtoul(buf, &e, 10);
        if (e==buf || (*e && *e != '\n') )
                return -EINVAL;
-       if (major >= sizeof(super_types)/sizeof(super_types[0]) ||
-           super_types[major].name == NULL)
+       if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
                return -ENOENT;
        mddev->major_version = major;
        mddev->minor_version = minor;
@@ -2859,6 +2928,37 @@ suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
 static struct md_sysfs_entry md_suspend_hi =
 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
 
+static ssize_t
+reshape_position_show(mddev_t *mddev, char *page)
+{
+       if (mddev->reshape_position != MaxSector)
+               return sprintf(page, "%llu\n",
+                              (unsigned long long)mddev->reshape_position);
+       strcpy(page, "none\n");
+       return 5;
+}
+
+static ssize_t
+reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
+{
+       char *e;
+       unsigned long long new = simple_strtoull(buf, &e, 10);
+       if (mddev->pers)
+               return -EBUSY;
+       if (buf == e || (*e && *e != '\n'))
+               return -EINVAL;
+       mddev->reshape_position = new;
+       mddev->delta_disks = 0;
+       mddev->new_level = mddev->level;
+       mddev->new_layout = mddev->layout;
+       mddev->new_chunk = mddev->chunk_size;
+       return len;
+}
+
+static struct md_sysfs_entry md_reshape_position =
+__ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
+       reshape_position_store);
+
 
 static struct attribute *md_default_attrs[] = {
        &md_level.attr,
@@ -2871,6 +2971,7 @@ static struct attribute *md_default_attrs[] = {
        &md_new_device.attr,
        &md_safe_delay.attr,
        &md_array_state.attr,
+       &md_reshape_position.attr,
        NULL,
 };
 
@@ -3074,13 +3175,33 @@ static int do_md_run(mddev_t * mddev)
         * Drop all container device buffers, from now on
         * the only valid external interface is through the md
         * device.
-        * Also find largest hardsector size
         */
        ITERATE_RDEV(mddev,rdev,tmp) {
                if (test_bit(Faulty, &rdev->flags))
                        continue;
                sync_blockdev(rdev->bdev);
                invalidate_bdev(rdev->bdev);
+
+               /* perform some consistency tests on the device.
+                * We don't want the data to overlap the metadata,
+                * Internal Bitmap issues has handled elsewhere.
+                */
+               if (rdev->data_offset < rdev->sb_offset) {
+                       if (mddev->size &&
+                           rdev->data_offset + mddev->size*2
+                           > rdev->sb_offset*2) {
+                               printk("md: %s: data overlaps metadata\n",
+                                      mdname(mddev));
+                               return -EINVAL;
+                       }
+               } else {
+                       if (rdev->sb_offset*2 + rdev->sb_size/512
+                           > rdev->data_offset) {
+                               printk("md: %s: metadata overlaps data\n",
+                                      mdname(mddev));
+                               return -EINVAL;
+                       }
+               }
        }
 
        md_probe(mddev->unit, NULL, NULL);
@@ -3409,6 +3530,7 @@ static int do_md_stop(mddev_t * mddev, int mode)
                mddev->size = 0;
                mddev->raid_disks = 0;
                mddev->recovery_cp = 0;
+               mddev->reshape_position = MaxSector;
 
        } else if (mddev->pers)
                printk(KERN_INFO "md: %s switched to read-only mode.\n",
@@ -4019,7 +4141,7 @@ static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
        if (info->raid_disks == 0) {
                /* just setting version number for superblock loading */
                if (info->major_version < 0 ||
-                   info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
+                   info->major_version >= ARRAY_SIZE(super_types) ||
                    super_types[info->major_version].name == NULL) {
                        /* maybe try to auto-load a module? */
                        printk(KERN_INFO 
@@ -4541,7 +4663,6 @@ static int md_thread(void * arg)
         * many dirty RAID5 blocks.
         */
 
-       current->flags |= PF_NOFREEZE;
        allow_signal(SIGKILL);
        while (!kthread_should_stop()) {
 
@@ -4941,15 +5062,6 @@ static int md_seq_open(struct inode *inode, struct file *file)
        return error;
 }
 
-static int md_seq_release(struct inode *inode, struct file *file)
-{
-       struct seq_file *m = file->private_data;
-       struct mdstat_info *mi = m->private;
-       m->private = NULL;
-       kfree(mi);
-       return seq_release(inode, file);
-}
-
 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
 {
        struct seq_file *m = filp->private_data;
@@ -4971,7 +5083,7 @@ static const struct file_operations md_seq_fops = {
        .open           = md_seq_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
-       .release        = md_seq_release,
+       .release        = seq_release_private,
        .poll           = mdstat_poll,
 };
 
@@ -4998,7 +5110,7 @@ static int is_mddev_idle(mddev_t *mddev)
        mdk_rdev_t * rdev;
        struct list_head *tmp;
        int idle;
-       unsigned long curr_events;
+       long curr_events;
 
        idle = 1;
        ITERATE_RDEV(mddev,rdev,tmp) {
@@ -5006,20 +5118,29 @@ static int is_mddev_idle(mddev_t *mddev)
                curr_events = disk_stat_read(disk, sectors[0]) + 
                                disk_stat_read(disk, sectors[1]) - 
                                atomic_read(&disk->sync_io);
-               /* The difference between curr_events and last_events
-                * will be affected by any new non-sync IO (making
-                * curr_events bigger) and any difference in the amount of
-                * in-flight syncio (making current_events bigger or smaller)
-                * The amount in-flight is currently limited to
-                * 32*64K in raid1/10 and 256*PAGE_SIZE in raid5/6
-                * which is at most 4096 sectors.
-                * These numbers are fairly fragile and should be made
-                * more robust, probably by enforcing the
-                * 'window size' that md_do_sync sort-of uses.
+               /* sync IO will cause sync_io to increase before the disk_stats
+                * as sync_io is counted when a request starts, and
+                * disk_stats is counted when it completes.
+                * So resync activity will cause curr_events to be smaller than
+                * when there was no such activity.
+                * non-sync IO will cause disk_stat to increase without
+                * increasing sync_io so curr_events will (eventually)
+                * be larger than it was before.  Once it becomes
+                * substantially larger, the test below will cause
+                * the array to appear non-idle, and resync will slow
+                * down.
+                * If there is a lot of outstanding resync activity when
+                * we set last_event to curr_events, then all that activity
+                * completing might cause the array to appear non-idle
+                * and resync will be slowed down even though there might
+                * not have been non-resync activity.  This will only
+                * happen once though.  'last_events' will soon reflect
+                * the state where there is little or no outstanding
+                * resync requests, and further resync activity will
+                * always make curr_events less than last_events.
                 *
-                * Note: the following is an unsigned comparison.
                 */
-               if ((curr_events - rdev->last_events + 4096) > 8192) {
+               if (curr_events - rdev->last_events > 4096) {
                        rdev->last_events = curr_events;
                        idle = 0;
                }
@@ -5680,7 +5801,7 @@ static void autostart_arrays(int part)
        for (i = 0; i < dev_cnt; i++) {
                dev_t dev = detected_devices[i];
 
-               rdev = md_import_device(dev,0, 0);
+               rdev = md_import_device(dev,0, 90);
                if (IS_ERR(rdev))
                        continue;
 
@@ -5722,7 +5843,7 @@ static __exit void md_exit(void)
        }
 }
 
-module_init(md_init)
+subsys_initcall(md_init);
 module_exit(md_exit)
 
 static int get_ro(char *buffer, struct kernel_param *kp)