| Message ID | 20200403101250.33245-7-johannes.thumshirn@wdc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Introduce Zone Append for writing to zoned block devices | expand |
On Fri, Apr 03, 2020 at 07:12:46PM +0900, Johannes Thumshirn wrote: > scsi_mq_uninit_cmnd is used to free the sg_tables, uninitialize the > command and delete it from the command list. > > Export this function so it can be used from modular code to free the > memory allocated by scsi_init_io() if the caller of scsi_init_io() needs > to do error recovery. Hmm. scsi_mq_uninit_cmnd does three things: - calls ->uninit_command, but that is something the driver can trivially do itself. - scsi_mq_free_sgtables - yes, this would need to be done by the driver and actually is what undoes scsi_init_io. I think you want to export this instead (and remove the _mq in the name while you are at it) - scsi_del_cmd_from_list - this undoes scsi_add_cmd_to_list, which is not related to what the upper level driver does
On 07/04/2020 19:00, Christoph Hellwig wrote: > - scsi_mq_free_sgtables - yes, this would need to be done by the driver > and actually is what undoes scsi_init_io. I think you want to export > this instead (and remove the _mq in the name while you are at it) OK, I was afraid to expose too much internals if I export scsi_mq_free_sgtables() but, sure that's a trivial change.
On Wed, Apr 08, 2020 at 11:32:30AM +0000, Johannes Thumshirn wrote: > On 07/04/2020 19:00, Christoph Hellwig wrote: > > - scsi_mq_free_sgtables - yes, this would need to be done by the driver > > and actually is what undoes scsi_init_io. I think you want to export > > this instead (and remove the _mq in the name while you are at it) > > OK, I was afraid to expose too much internals if I export > scsi_mq_free_sgtables() but, sure that's a trivial change. Well, it mirrors scsi_init_io, so if we want to undo scsi_init_io it seems to be the right export.
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index ea327f320b7f..4646575a89d6 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -57,8 +57,6 @@ static struct kmem_cache *scsi_sense_cache; static struct kmem_cache *scsi_sense_isadma_cache; static DEFINE_MUTEX(scsi_sense_cache_mutex); -static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd); - static inline struct kmem_cache * scsi_select_sense_cache(bool unchecked_isa_dma) { @@ -558,12 +556,17 @@ static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd) SCSI_INLINE_PROT_SG_CNT); } -static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) +/** + * scsi_mq_uninit_cmd - uninitialize a SCSI command + * @cmd: the command to free + */ +void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) { scsi_mq_free_sgtables(cmd); scsi_uninit_cmd(cmd); scsi_del_cmd_from_list(cmd); } +EXPORT_SYMBOL_GPL(scsi_mq_uninit_cmd); /* Returns false when no more bytes to process, true if there are more */ static bool scsi_end_request(struct request *req, blk_status_t error, diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index a2849bb9cd19..65ff625db38b 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -167,6 +167,7 @@ extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, extern void scsi_kunmap_atomic_sg(void *virt); extern blk_status_t scsi_init_io(struct scsi_cmnd *cmd); +extern void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd); #ifdef CONFIG_SCSI_DMA extern int scsi_dma_map(struct scsi_cmnd *cmd);
scsi_mq_uninit_cmnd is used to free the sg_tables, uninitialize the command and delete it from the command list. Export this function so it can be used from modular code to free the memory allocated by scsi_init_io() if the caller of scsi_init_io() needs to do error recovery. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> --- drivers/scsi/scsi_lib.c | 9 ++++++--- include/scsi/scsi_cmnd.h | 1 + 2 files changed, 7 insertions(+), 3 deletions(-)