ping ? Any comments on this clean up patch ?
On 1/18/2023 9:16 PM, Hou Tao wrote:
> ping ?
>
> On 12/16/2022 12:23 PM, Hou Tao wrote:
>> From: Hou Tao <houtao1@xxxxxxxxxx>
>>
>> __hash_remove() removes hash_cell with _hash_lock locked, so acquiring
>> _hash_lock can guarantee no-NULL hc returned from dm_get_mdptr() must
>> have not been removed and hc->md must still be md.
>>
>> __hash_remove() also acquires dm_hash_cells_mutex before setting mdptr
>> as NULL, so in dm_copy_name_and_uuid() after acquiring
>> dm_hash_cells_mutex and ensuring returned hc is not NULL, the returned
>> hc must still be alive and hc->md must still be md.
>>
>> So removing these unnecessary hc->md != md checks when using
>> dm_get_mdptr() with _hash_lock or dm_hash_cells_mutex acquired.
>>
>> Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
>> ---
>> drivers/md/dm-ioctl.c | 6 +++---
>> 1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
>> index 3bfc1583c20a..2a86524661d1 100644
>> --- a/drivers/md/dm-ioctl.c
>> +++ b/drivers/md/dm-ioctl.c
>> @@ -772,7 +772,7 @@ static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *src
>>
>> down_read(&_hash_lock);
>> hc = dm_get_mdptr(md);
>> - if (!hc || hc->md != md) {
>> + if (!hc) {
>> DMERR("device has been removed from the dev hash table.");
>> goto out;
>> }
>> @@ -1476,7 +1476,7 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si
>> /* stage inactive table */
>> down_write(&_hash_lock);
>> hc = dm_get_mdptr(md);
>> - if (!hc || hc->md != md) {
>> + if (!hc) {
>> DMERR("device has been removed from the dev hash table.");
>> up_write(&_hash_lock);
>> r = -ENXIO;
>> @@ -2128,7 +2128,7 @@ int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
>>
>> mutex_lock(&dm_hash_cells_mutex);
>> hc = dm_get_mdptr(md);
>> - if (!hc || hc->md != md) {
>> + if (!hc) {
>> r = -ENXIO;
>> goto out;
>> }
--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://listman.redhat.com/mailman/listinfo/dm-devel
