1 files changed, 159 insertions, 113 deletions

diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 7d6b34e201db..7408227c49c9 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -120,22 +120,21 @@ static int (*check_part[])(struct parsed_partitions *, struct block_device *) =
  * a pointer to that same buffer (for convenience).
  */
 
-char *disk_name(struct gendisk *hd, int part, char *buf)
+char *disk_name(struct gendisk *hd, int partno, char *buf)
 {
-        if (!part)
+        if (!partno)
                 snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
         else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
-                snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, part);
+                snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
         else
-                snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, part);
+                snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
 
         return buf;
 }
 
 const char *bdevname(struct block_device *bdev, char *buf)
 {
-        int part = MINOR(bdev->bd_dev) - bdev->bd_disk->first_minor;
-        return disk_name(bdev->bd_disk, part, buf);
+        return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
 }
 
 EXPORT_SYMBOL(bdevname);
@@ -169,7 +168,7 @@ check_partition(struct gendisk *hd, struct block_device *bdev)
         if (isdigit(state->name[strlen(state->name)-1]))
                 sprintf(state->name, "p");
 
-        state->limit = hd->minors;
+        state->limit = disk_max_parts(hd);
         i = res = err = 0;
         while (!res && check_part[i]) {
                 memset(&state->parts, 0, sizeof(state->parts));
@@ -204,21 +203,22 @@ static ssize_t part_start_show(struct device *dev,
         return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
 }
 
-static ssize_t part_size_show(struct device *dev,
-                              struct device_attribute *attr, char *buf)
+ssize_t part_size_show(struct device *dev,
+                       struct device_attribute *attr, char *buf)
 {
         struct hd_struct *p = dev_to_part(dev);
         return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
 }
 
-static ssize_t part_stat_show(struct device *dev,
-                              struct device_attribute *attr, char *buf)
+ssize_t part_stat_show(struct device *dev,
+                       struct device_attribute *attr, char *buf)
 {
         struct hd_struct *p = dev_to_part(dev);
+        int cpu;
 
-        preempt_disable();
-        part_round_stats(p);
-        preempt_enable();
+        cpu = part_stat_lock();
+        part_round_stats(cpu, p);
+        part_stat_unlock();
         return sprintf(buf,
                 "%8lu %8lu %8llu %8u "
                 "%8lu %8lu %8llu %8u "
@@ -238,17 +238,17 @@ static ssize_t part_stat_show(struct device *dev,
 }
 
 #ifdef CONFIG_FAIL_MAKE_REQUEST
-static ssize_t part_fail_show(struct device *dev,
-                              struct device_attribute *attr, char *buf)
+ssize_t part_fail_show(struct device *dev,
+                       struct device_attribute *attr, char *buf)
 {
         struct hd_struct *p = dev_to_part(dev);
 
         return sprintf(buf, "%d\n", p->make_it_fail);
 }
 
-static ssize_t part_fail_store(struct device *dev,
-                               struct device_attribute *attr,
-                               const char *buf, size_t count)
+ssize_t part_fail_store(struct device *dev,
+                        struct device_attribute *attr,
+                        const char *buf, size_t count)
 {
         struct hd_struct *p = dev_to_part(dev);
         int i;
@@ -300,40 +300,34 @@ struct device_type part_type = {
         .release        = part_release,
 };
 
-static inline void partition_sysfs_add_subdir(struct hd_struct *p)
-{
-        struct kobject *k;
-
-        k = kobject_get(&p->dev.kobj);
-        p->holder_dir = kobject_create_and_add("holders", k);
-        kobject_put(k);
-}
-
-static inline void disk_sysfs_add_subdirs(struct gendisk *disk)
+static void delete_partition_rcu_cb(struct rcu_head *head)
 {
-        struct kobject *k;
+        struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
 
-        k = kobject_get(&disk->dev.kobj);
-        disk->holder_dir = kobject_create_and_add("holders", k);
-        disk->slave_dir = kobject_create_and_add("slaves", k);
-        kobject_put(k);
+        part->start_sect = 0;
+        part->nr_sects = 0;
+        part_stat_set_all(part, 0);
+        put_device(part_to_dev(part));
 }
 
-void delete_partition(struct gendisk *disk, int part)
+void delete_partition(struct gendisk *disk, int partno)
 {
-        struct hd_struct *p = disk->part[part-1];
+        struct disk_part_tbl *ptbl = disk->part_tbl;
+        struct hd_struct *part;
 
-        if (!p)
+        if (partno >= ptbl->len)
                 return;
-        if (!p->nr_sects)
+
+        part = ptbl->part[partno];
+        if (!part)
                 return;
-        disk->part[part-1] = NULL;
-        p->start_sect = 0;
-        p->nr_sects = 0;
-        part_stat_set_all(p, 0);
-        kobject_put(p->holder_dir);
-        device_del(&p->dev);
-        put_device(&p->dev);
+
+        blk_free_devt(part_devt(part));
+        rcu_assign_pointer(ptbl->part[partno], NULL);
+        kobject_put(part->holder_dir);
+        device_del(part_to_dev(part));
+
+        call_rcu(&part->rcu_head, delete_partition_rcu_cb);
 }
 
 static ssize_t whole_disk_show(struct device *dev,
@@ -344,102 +338,132 @@ static ssize_t whole_disk_show(struct device *dev,
 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
                    whole_disk_show, NULL);
 
-int add_partition(struct gendisk *disk, int part, sector_t start, sector_t len, int flags)
+int add_partition(struct gendisk *disk, int partno,
+                  sector_t start, sector_t len, int flags)
 {
         struct hd_struct *p;
+        dev_t devt = MKDEV(0, 0);
+        struct device *ddev = disk_to_dev(disk);
+        struct device *pdev;
+        struct disk_part_tbl *ptbl;
+        const char *dname;
         int err;
 
+        err = disk_expand_part_tbl(disk, partno);
+        if (err)
+                return err;
+        ptbl = disk->part_tbl;
+
+        if (ptbl->part[partno])
+                return -EBUSY;
+
         p = kzalloc(sizeof(*p), GFP_KERNEL);
         if (!p)
                 return -ENOMEM;
 
         if (!init_part_stats(p)) {
                 err = -ENOMEM;
-                goto out0;
+                goto out_free;
         }
+        pdev = part_to_dev(p);
+
         p->start_sect = start;
         p->nr_sects = len;
-        p->partno = part;
-        p->policy = disk->policy;
+        p->partno = partno;
+        p->policy = get_disk_ro(disk);
 
-        if (isdigit(disk->dev.bus_id[strlen(disk->dev.bus_id)-1]))
-                snprintf(p->dev.bus_id, BUS_ID_SIZE,
-                "%sp%d", disk->dev.bus_id, part);
+        dname = dev_name(ddev);
+        if (isdigit(dname[strlen(dname) - 1]))
+                snprintf(pdev->bus_id, BUS_ID_SIZE, "%sp%d", dname, partno);
         else
-                snprintf(p->dev.bus_id, BUS_ID_SIZE,
-                         "%s%d", disk->dev.bus_id, part);
+                snprintf(pdev->bus_id, BUS_ID_SIZE, "%s%d", dname, partno);
+
+        device_initialize(pdev);
+        pdev->class = &block_class;
+        pdev->type = &part_type;
+        pdev->parent = ddev;
 
-        device_initialize(&p->dev);
-        p->dev.devt = MKDEV(disk->major, disk->first_minor + part);
-        p->dev.class = &block_class;
-        p->dev.type = &part_type;
-        p->dev.parent = &disk->dev;
-        disk->part[part-1] = p;
+        err = blk_alloc_devt(p, &devt);
+        if (err)
+                goto out_free;
+        pdev->devt = devt;
 
         /* delay uevent until 'holders' subdir is created */
-        p->dev.uevent_suppress = 1;
-        err = device_add(&p->dev);
+        pdev->uevent_suppress = 1;
+        err = device_add(pdev);
         if (err)
-                goto out1;
-        partition_sysfs_add_subdir(p);
-        p->dev.uevent_suppress = 0;
+                goto out_put;
+
+        err = -ENOMEM;
+        p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
+        if (!p->holder_dir)
+                goto out_del;
+
+        pdev->uevent_suppress = 0;
         if (flags & ADDPART_FLAG_WHOLEDISK) {
-                err = device_create_file(&p->dev, &dev_attr_whole_disk);
+                err = device_create_file(pdev, &dev_attr_whole_disk);
                 if (err)
-                        goto out2;
+                        goto out_del;
         }
 
+        /* everything is up and running, commence */
+        INIT_RCU_HEAD(&p->rcu_head);
+        rcu_assign_pointer(ptbl->part[partno], p);
+
         /* suppress uevent if the disk supresses it */
-        if (!disk->dev.uevent_suppress)
-                kobject_uevent(&p->dev.kobj, KOBJ_ADD);
+        if (!ddev->uevent_suppress)
+                kobject_uevent(&pdev->kobj, KOBJ_ADD);
 
         return 0;
 
-out2:
-        device_del(&p->dev);
-out1:
-        put_device(&p->dev);
-        free_part_stats(p);
-out0:
+out_free:
         kfree(p);
         return err;
+out_del:
+        kobject_put(p->holder_dir);
+        device_del(pdev);
+out_put:
+        put_device(pdev);
+        blk_free_devt(devt);
+        return err;
 }
 
 /* Not exported, helper to add_disk(). */
 void register_disk(struct gendisk *disk)
 {
+        struct device *ddev = disk_to_dev(disk);
         struct block_device *bdev;
+        struct disk_part_iter piter;
+        struct hd_struct *part;
         char *s;
-        int i;
-        struct hd_struct *p;
         int err;
 
-        disk->dev.parent = disk->driverfs_dev;
-        disk->dev.devt = MKDEV(disk->major, disk->first_minor);
+        ddev->parent = disk->driverfs_dev;
 
-        strlcpy(disk->dev.bus_id, disk->disk_name, BUS_ID_SIZE);
+        strlcpy(ddev->bus_id, disk->disk_name, BUS_ID_SIZE);
         /* ewww... some of these buggers have / in the name... */
-        s = strchr(disk->dev.bus_id, '/');
+        s = strchr(ddev->bus_id, '/');
         if (s)
                 *s = '!';
 
         /* delay uevents, until we scanned partition table */
-        disk->dev.uevent_suppress = 1;
+        ddev->uevent_suppress = 1;
 
-        if (device_add(&disk->dev))
+        if (device_add(ddev))
                 return;
 #ifndef CONFIG_SYSFS_DEPRECATED
-        err = sysfs_create_link(block_depr, &disk->dev.kobj,
-                                kobject_name(&disk->dev.kobj));
+        err = sysfs_create_link(block_depr, &ddev->kobj,
+                                kobject_name(&ddev->kobj));
         if (err) {
-                device_del(&disk->dev);
+                device_del(ddev);
                 return;
         }
 #endif
-        disk_sysfs_add_subdirs(disk);
+        disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
+        disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
 
         /* No minors to use for partitions */
-        if (disk->minors == 1)
+        if (!disk_partitionable(disk))
                 goto exit;
 
         /* No such device (e.g., media were just removed) */
@@ -458,50 +482,66 @@ void register_disk(struct gendisk *disk)
 
 exit:
         /* announce disk after possible partitions are created */
-        disk->dev.uevent_suppress = 0;
-        kobject_uevent(&disk->dev.kobj, KOBJ_ADD);
+        ddev->uevent_suppress = 0;
+        kobject_uevent(&ddev->kobj, KOBJ_ADD);
 
         /* announce possible partitions */
-        for (i = 1; i < disk->minors; i++) {
-                p = disk->part[i-1];
-                if (!p || !p->nr_sects)
-                        continue;
-                kobject_uevent(&p->dev.kobj, KOBJ_ADD);
-        }
+        disk_part_iter_init(&piter, disk, 0);
+        while ((part = disk_part_iter_next(&piter)))
+                kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
+        disk_part_iter_exit(&piter);
 }
 
 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
 {
+        struct disk_part_iter piter;
+        struct hd_struct *part;
         struct parsed_partitions *state;
-        int p, res;
+        int p, highest, res;
 
         if (bdev->bd_part_count)
                 return -EBUSY;
         res = invalidate_partition(disk, 0);
         if (res)
                 return res;
-        bdev->bd_invalidated = 0;
-        for (p = 1; p < disk->minors; p++)
-                delete_partition(disk, p);
+
+        disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
+        while ((part = disk_part_iter_next(&piter)))
+                delete_partition(disk, part->partno);
+        disk_part_iter_exit(&piter);
+
         if (disk->fops->revalidate_disk)
                 disk->fops->revalidate_disk(disk);
+        check_disk_size_change(disk, bdev);
+        bdev->bd_invalidated = 0;
         if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
                 return 0;
         if (IS_ERR(state))      /* I/O error reading the partition table */
                 return -EIO;
 
         /* tell userspace that the media / partition table may have changed */
-        kobject_uevent(&disk->dev.kobj, KOBJ_CHANGE);
+        kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 
+        /* Detect the highest partition number and preallocate
+         * disk->part_tbl.  This is an optimization and not strictly
+         * necessary.
+         */
+        for (p = 1, highest = 0; p < state->limit; p++)
+                if (state->parts[p].size)
+                        highest = p;
+
+        disk_expand_part_tbl(disk, highest);
+
+        /* add partitions */
         for (p = 1; p < state->limit; p++) {
                 sector_t size = state->parts[p].size;
                 sector_t from = state->parts[p].from;
                 if (!size)
                         continue;
                 if (from + size > get_capacity(disk)) {
-                        printk(KERN_ERR " %s: p%d exceeds device capacity\n",
+                        printk(KERN_WARNING
+                                "%s: p%d exceeds device capacity\n",
                                 disk->disk_name, p);
-                        continue;
                 }
                 res = add_partition(disk, p, from, size, state->parts[p].flags);
                 if (res) {
@@ -541,25 +581,31 @@ EXPORT_SYMBOL(read_dev_sector);
 
 void del_gendisk(struct gendisk *disk)
 {
-        int p;
+        struct disk_part_iter piter;
+        struct hd_struct *part;
 
         /* invalidate stuff */
-        for (p = disk->minors - 1; p > 0; p--) {
-                invalidate_partition(disk, p);
-                delete_partition(disk, p);
+        disk_part_iter_init(&piter, disk,
+                             DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
+        while ((part = disk_part_iter_next(&piter))) {
+                invalidate_partition(disk, part->partno);
+                delete_partition(disk, part->partno);
         }
+        disk_part_iter_exit(&piter);
+
         invalidate_partition(disk, 0);
-        disk->capacity = 0;
+        blk_free_devt(disk_to_dev(disk)->devt);
+        set_capacity(disk, 0);
         disk->flags &= ~GENHD_FL_UP;
         unlink_gendisk(disk);
-        disk_stat_set_all(disk, 0);
-        disk->stamp = 0;
+        part_stat_set_all(&disk->part0, 0);
+        disk->part0.stamp = 0;
 
-        kobject_put(disk->holder_dir);
+        kobject_put(disk->part0.holder_dir);
         kobject_put(disk->slave_dir);
         disk->driverfs_dev = NULL;
 #ifndef CONFIG_SYSFS_DEPRECATED
-        sysfs_remove_link(block_depr, disk->dev.bus_id);
+        sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
 #endif
-        device_del(&disk->dev);
+        device_del(disk_to_dev(disk));
 }