zram: return zram device_id from zram_add()

This patch prepares zram to enable on-demand device creation.
zram_add() performs automatic device_id assignment and returns
new device id (>= 0) or error code (< 0).

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sergey Senozhatsky 2015-06-25 15:00:19 -07:00 коммит произвёл Linus Torvalds
Родитель b31177f2a9
Коммит 92ff152887
1 изменённых файлов: 14 добавлений и 9 удалений

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@ -1153,20 +1153,24 @@ static struct attribute_group zram_disk_attr_group = {
.attrs = zram_disk_attrs,
};
static int zram_add(int device_id)
/*
* Allocate and initialize new zram device. the function returns
* '>= 0' device_id upon success, and negative value otherwise.
*/
static int zram_add(void)
{
struct zram *zram;
struct request_queue *queue;
int ret;
int ret, device_id;
zram = kzalloc(sizeof(struct zram), GFP_KERNEL);
if (!zram)
return -ENOMEM;
ret = idr_alloc(&zram_index_idr, zram, device_id,
device_id + 1, GFP_KERNEL);
ret = idr_alloc(&zram_index_idr, zram, 0, 0, GFP_KERNEL);
if (ret < 0)
goto out_free_dev;
device_id = ret;
init_rwsem(&zram->init_lock);
@ -1240,7 +1244,7 @@ static int zram_add(int device_id)
zram->max_comp_streams = 1;
pr_info("Added device: %s\n", zram->disk->disk_name);
return 0;
return device_id;
out_free_disk:
del_gendisk(zram->disk);
@ -1287,7 +1291,7 @@ static void destroy_devices(void)
static int __init zram_init(void)
{
int ret, dev_id;
int ret;
zram_major = register_blkdev(0, "zram");
if (zram_major <= 0) {
@ -1295,10 +1299,11 @@ static int __init zram_init(void)
return -EBUSY;
}
for (dev_id = 0; dev_id < num_devices; dev_id++) {
ret = zram_add(dev_id);
if (ret != 0)
while (num_devices != 0) {
ret = zram_add();
if (ret < 0)
goto out_error;
num_devices--;
}
return 0;