[PATCH 24/45] blk-cgroup: stop abusing get_gendisk
Christoph Hellwig
hch at lst.de
Tue Nov 24 08:27:30 EST 2020
Properly open the device instead of relying on deep internals by
using get_gendisk. Note that this uses FMODE_NDELAY without either
FMODE_READ or FMODE_WRITE, which is a special open mode to allow
for opening without media access, thus avoiding unexpexted interactions
especially on removable media.
Signed-off-by: Christoph Hellwig <hch at lst.de>
---
block/blk-cgroup.c | 42 +++++++++++++++++++-------------------
block/blk-iocost.c | 36 ++++++++++++++++----------------
include/linux/blk-cgroup.h | 4 ++--
3 files changed, 41 insertions(+), 41 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 54fbe1e80cc41a..23437b96ea41e6 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -556,22 +556,22 @@ static struct blkcg_gq *blkg_lookup_check(struct blkcg *blkcg,
}
/**
- * blkg_conf_prep - parse and prepare for per-blkg config update
+ * blkcg_conf_open_bdev - parse and open bdev for per-blkg config update
* @inputp: input string pointer
*
* Parse the device node prefix part, MAJ:MIN, of per-blkg config update
- * from @input and get and return the matching gendisk. *@inputp is
+ * from @input and get and return the matching bdev. *@inputp is
* updated to point past the device node prefix. Returns an ERR_PTR()
* value on error.
*
* Use this function iff blkg_conf_prep() can't be used for some reason.
*/
-struct gendisk *blkcg_conf_get_disk(char **inputp)
+struct block_device *blkcg_conf_open_bdev(char **inputp)
{
char *input = *inputp;
unsigned int major, minor;
- struct gendisk *disk;
- int key_len, part;
+ struct block_device *bdev;
+ int key_len;
if (sscanf(input, "%u:%u%n", &major, &minor, &key_len) != 2)
return ERR_PTR(-EINVAL);
@@ -581,16 +581,16 @@ struct gendisk *blkcg_conf_get_disk(char **inputp)
return ERR_PTR(-EINVAL);
input = skip_spaces(input);
- disk = get_gendisk(MKDEV(major, minor), &part);
- if (!disk)
+ bdev = blkdev_get_by_dev(MKDEV(major, minor), FMODE_NDELAY, NULL);
+ if (!bdev)
return ERR_PTR(-ENODEV);
- if (part) {
- put_disk_and_module(disk);
+ if (bdev_is_partition(bdev)) {
+ blkdev_put(bdev, FMODE_NDELAY);
return ERR_PTR(-ENODEV);
}
*inputp = input;
- return disk;
+ return bdev;
}
/**
@@ -607,18 +607,18 @@ struct gendisk *blkcg_conf_get_disk(char **inputp)
*/
int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
char *input, struct blkg_conf_ctx *ctx)
- __acquires(rcu) __acquires(&disk->queue->queue_lock)
+ __acquires(rcu) __acquires(&bdev->bd_disk->queue->queue_lock)
{
- struct gendisk *disk;
+ struct block_device *bdev;
struct request_queue *q;
struct blkcg_gq *blkg;
int ret;
- disk = blkcg_conf_get_disk(&input);
- if (IS_ERR(disk))
- return PTR_ERR(disk);
+ bdev = blkcg_conf_open_bdev(&input);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
- q = disk->queue;
+ q = bdev->bd_disk->queue;
rcu_read_lock();
spin_lock_irq(&q->queue_lock);
@@ -689,7 +689,7 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
goto success;
}
success:
- ctx->disk = disk;
+ ctx->bdev = bdev;
ctx->blkg = blkg;
ctx->body = input;
return 0;
@@ -700,7 +700,7 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
spin_unlock_irq(&q->queue_lock);
rcu_read_unlock();
fail:
- put_disk_and_module(disk);
+ blkdev_put(bdev, FMODE_NDELAY);
/*
* If queue was bypassing, we should retry. Do so after a
* short msleep(). It isn't strictly necessary but queue
@@ -723,11 +723,11 @@ EXPORT_SYMBOL_GPL(blkg_conf_prep);
* with blkg_conf_prep().
*/
void blkg_conf_finish(struct blkg_conf_ctx *ctx)
- __releases(&ctx->disk->queue->queue_lock) __releases(rcu)
+ __releases(&ctx->bdev->bd_disk->queue->queue_lock) __releases(rcu)
{
- spin_unlock_irq(&ctx->disk->queue->queue_lock);
+ spin_unlock_irq(&ctx->bdev->bd_disk->queue->queue_lock);
rcu_read_unlock();
- put_disk_and_module(ctx->disk);
+ blkdev_put(ctx->bdev, FMODE_NDELAY);
}
EXPORT_SYMBOL_GPL(blkg_conf_finish);
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index bbe86d1199dc5b..9f219718e9813c 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -3120,23 +3120,23 @@ static const match_table_t qos_tokens = {
static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
size_t nbytes, loff_t off)
{
- struct gendisk *disk;
+ struct block_device *bdev;
struct ioc *ioc;
u32 qos[NR_QOS_PARAMS];
bool enable, user;
char *p;
int ret;
- disk = blkcg_conf_get_disk(&input);
- if (IS_ERR(disk))
- return PTR_ERR(disk);
+ bdev = blkcg_conf_open_bdev(&input);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
- ioc = q_to_ioc(disk->queue);
+ ioc = q_to_ioc(bdev->bd_disk->queue);
if (!ioc) {
- ret = blk_iocost_init(disk->queue);
+ ret = blk_iocost_init(bdev->bd_disk->queue);
if (ret)
goto err;
- ioc = q_to_ioc(disk->queue);
+ ioc = q_to_ioc(bdev->bd_disk->queue);
}
spin_lock_irq(&ioc->lock);
@@ -3231,12 +3231,12 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);
- put_disk_and_module(disk);
+ blkdev_put(bdev, FMODE_NDELAY);
return nbytes;
einval:
ret = -EINVAL;
err:
- put_disk_and_module(disk);
+ blkdev_put(bdev, FMODE_NDELAY);
return ret;
}
@@ -3287,23 +3287,23 @@ static const match_table_t i_lcoef_tokens = {
static ssize_t ioc_cost_model_write(struct kernfs_open_file *of, char *input,
size_t nbytes, loff_t off)
{
- struct gendisk *disk;
+ struct block_device *bdev;
struct ioc *ioc;
u64 u[NR_I_LCOEFS];
bool user;
char *p;
int ret;
- disk = blkcg_conf_get_disk(&input);
- if (IS_ERR(disk))
- return PTR_ERR(disk);
+ bdev = blkcg_conf_open_bdev(&input);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
- ioc = q_to_ioc(disk->queue);
+ ioc = q_to_ioc(bdev->bd_disk->queue);
if (!ioc) {
- ret = blk_iocost_init(disk->queue);
+ ret = blk_iocost_init(bdev->bd_disk->queue);
if (ret)
goto err;
- ioc = q_to_ioc(disk->queue);
+ ioc = q_to_ioc(bdev->bd_disk->queue);
}
spin_lock_irq(&ioc->lock);
@@ -3356,13 +3356,13 @@ static ssize_t ioc_cost_model_write(struct kernfs_open_file *of, char *input,
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);
- put_disk_and_module(disk);
+ blkdev_put(bdev, FMODE_NDELAY);
return nbytes;
einval:
ret = -EINVAL;
err:
- put_disk_and_module(disk);
+ blkdev_put(bdev, FMODE_NDELAY);
return ret;
}
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index c8fc9792ac776d..b9f3c246c3c908 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -197,12 +197,12 @@ void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v);
struct blkg_conf_ctx {
- struct gendisk *disk;
+ struct block_device *bdev;
struct blkcg_gq *blkg;
char *body;
};
-struct gendisk *blkcg_conf_get_disk(char **inputp);
+struct block_device *blkcg_conf_open_bdev(char **inputp);
int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
char *input, struct blkg_conf_ctx *ctx);
void blkg_conf_finish(struct blkg_conf_ctx *ctx);
--
2.29.2
More information about the linux-mtd
mailing list