Merge branch 'linux-linaro-lsk' into linux-linaro-lsk-android

[firefly-linux-kernel-4.4.55.git] / block / genhd.c

diff --git a/block/genhd.c b/block/genhd.c
index cdeb5277dfd402ddeefa300d888d8e07b81b8ad9..2d350aae2eb66185f02bb6ac3b9bf6d741716dff 100644 (file)
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -28,10 +28,10 @@ struct kobject *block_depr;
 /* for extended dynamic devt allocation, currently only one major is used */
 #define NR_EXT_DEVT            (1 << MINORBITS)
 
-/* For extended devt allocation.  ext_devt_mutex prevents look up
+/* For extended devt allocation.  ext_devt_lock prevents look up
  * results from going away underneath its user.
  */
-static DEFINE_MUTEX(ext_devt_mutex);
+static DEFINE_SPINLOCK(ext_devt_lock);
 static DEFINE_IDR(ext_devt_idr);
 
 static struct device_type disk_type;
@@ -420,9 +420,13 @@ int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
        }
 
        /* allocate ext devt */
-       mutex_lock(&ext_devt_mutex);
-       idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_KERNEL);
-       mutex_unlock(&ext_devt_mutex);
+       idr_preload(GFP_KERNEL);
+
+       spin_lock(&ext_devt_lock);
+       idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_NOWAIT);
+       spin_unlock(&ext_devt_lock);
+
+       idr_preload_end();
        if (idx < 0)
                return idx == -ENOSPC ? -EBUSY : idx;
 
@@ -441,15 +445,13 @@ int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
  */
 void blk_free_devt(dev_t devt)
 {
-       might_sleep();
-
        if (devt == MKDEV(0, 0))
                return;
 
        if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
-               mutex_lock(&ext_devt_mutex);
+               spin_lock(&ext_devt_lock);
                idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
-               mutex_unlock(&ext_devt_mutex);
+               spin_unlock(&ext_devt_lock);
        }
 }
 
@@ -665,7 +667,6 @@ void del_gendisk(struct gendisk *disk)
                sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
        pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
        device_del(disk_to_dev(disk));
-       blk_free_devt(disk_to_dev(disk)->devt);
 }
 EXPORT_SYMBOL(del_gendisk);
 
@@ -690,13 +691,13 @@ struct gendisk *get_gendisk(dev_t devt, int *partno)
        } else {
                struct hd_struct *part;
 
-               mutex_lock(&ext_devt_mutex);
+               spin_lock(&ext_devt_lock);
                part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
                if (part && get_disk(part_to_disk(part))) {
                        *partno = part->partno;
                        disk = part_to_disk(part);
                }
-               mutex_unlock(&ext_devt_mutex);
+               spin_unlock(&ext_devt_lock);
        }
 
        return disk;
@@ -1069,9 +1070,16 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno)
        struct disk_part_tbl *old_ptbl = disk->part_tbl;
        struct disk_part_tbl *new_ptbl;
        int len = old_ptbl ? old_ptbl->len : 0;
-       int target = partno + 1;
+       int i, target;
        size_t size;
-       int i;
+
+       /*
+        * check for int overflow, since we can get here from blkpg_ioctl()
+        * with a user passed 'partno'.
+        */
+       target = partno + 1;
+       if (target < 0)
+               return -EINVAL;
 
        /* disk_max_parts() is zero during initialization, ignore if so */
        if (disk_max_parts(disk) && target > disk_max_parts(disk))
@@ -1098,6 +1106,7 @@ static void disk_release(struct device *dev)
 {
        struct gendisk *disk = dev_to_disk(dev);
 
+       blk_free_devt(dev->devt);
        disk_release_events(disk);
        kfree(disk->random);
        disk_replace_part_tbl(disk, NULL);
@@ -1107,6 +1116,22 @@ static void disk_release(struct device *dev)
                blk_put_queue(disk->queue);
        kfree(disk);
 }
+
+static int disk_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+       struct gendisk *disk = dev_to_disk(dev);
+       struct disk_part_iter piter;
+       struct hd_struct *part;
+       int cnt = 0;
+
+       disk_part_iter_init(&piter, disk, 0);
+       while((part = disk_part_iter_next(&piter)))
+               cnt++;
+       disk_part_iter_exit(&piter);
+       add_uevent_var(env, "NPARTS=%u", cnt);
+       return 0;
+}
+
 struct class block_class = {
        .name           = "block",
 };
@@ -1126,6 +1151,7 @@ static struct device_type disk_type = {
        .groups         = disk_attr_groups,
        .release        = disk_release,
        .devnode        = block_devnode,
+       .uevent         = disk_uevent,
 };
 
 #ifdef CONFIG_PROC_FS
@@ -1489,9 +1515,11 @@ static void __disk_unblock_events(struct gendisk *disk, bool check_now)
        intv = disk_events_poll_jiffies(disk);
        set_timer_slack(&ev->dwork.timer, intv / 4);
        if (check_now)
-               queue_delayed_work(system_freezable_wq, &ev->dwork, 0);
+               queue_delayed_work(system_freezable_power_efficient_wq,
+                               &ev->dwork, 0);
        else if (intv)
-               queue_delayed_work(system_freezable_wq, &ev->dwork, intv);
+               queue_delayed_work(system_freezable_power_efficient_wq,
+                               &ev->dwork, intv);
 out_unlock:
        spin_unlock_irqrestore(&ev->lock, flags);
 }
@@ -1534,7 +1562,8 @@ void disk_flush_events(struct gendisk *disk, unsigned int mask)
        spin_lock_irq(&ev->lock);
        ev->clearing |= mask;
        if (!ev->block)
-               mod_delayed_work(system_freezable_wq, &ev->dwork, 0);
+               mod_delayed_work(system_freezable_power_efficient_wq,
+                               &ev->dwork, 0);
        spin_unlock_irq(&ev->lock);
 }
 
@@ -1627,7 +1656,8 @@ static void disk_check_events(struct disk_events *ev,
 
        intv = disk_events_poll_jiffies(disk);
        if (!ev->block && intv)
-               queue_delayed_work(system_freezable_wq, &ev->dwork, intv);
+               queue_delayed_work(system_freezable_power_efficient_wq,
+                               &ev->dwork, intv);
 
        spin_unlock_irq(&ev->lock);