kernel/git/next/linux-next.git/include/scsi, branch akpm

scsi: libiscsi: Improve conn_send_pdu API

2022-06-22T01:19:23+00:00

The conn_send_pdu API is evil in that it returns a pointer to an iscsi_task, but that task might have been freed already so you can't touch it. This patch splits the task allocation and transmission, so functions like iscsi_send_nopout() can access the task before its sent and do whatever bookkeeping is needed before it is sent. Link: https://lore.kernel.org/r/20220616224557.115234-10-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Remove iscsi_get_task back_lock requirement

2022-06-22T01:19:23+00:00

We currently require that the back_lock is held when calling the functions that manipulate the iscsi_task refcount. The only reason for this is to handle races where we are handling SCSI-ml EH callbacks and the cmd is completing at the same time the normal completion path is running, and we can't return from the EH callback until the driver has stopped accessing the cmd. Holding the back_lock while also accessing the task->state made it simple to check that a cmd is completing and also get/put a refcount at the same time, and at the time we were not as concerned about performance. The problem is that we don't want to take the back_lock from the xmit path for normal I/O since it causes contention with the completion path if the user has chosen to try and split those paths on different CPUs (in this case abusing the CPUs and ignoring caching improves perf for some uses). Begins to remove the back_lock requirement for iscsi_get/put_task by removing the requirement for the get path. Instead of always holding the back_lock we detect if something has done the last put and is about to call iscsi_free_task(). A subsequent commit will then allow iSCSI code to do the last put on a task and only grab the back_lock if the refcount is now zero and it's going to call iscsi_free_task(). Link: https://lore.kernel.org/r/20220616224557.115234-8-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Add recv workqueue helpers

2022-06-22T01:19:22+00:00

Add helpers to allow the drivers to run their recv paths from libiscsi's workqueue. Link: https://lore.kernel.org/r/20220616224557.115234-3-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Rename iscsi_conn_queue_work()

2022-06-22T01:19:22+00:00

Rename iscsi_conn_queue_work() to iscsi_conn_queue_xmit() to reflect that it handles queueing of xmits only. Link: https://lore.kernel.org/r/20220616224557.115234-2-michael.christie@oracle.com Reviewed-by: Lee Duncan Reviewed-by: Wu Bo Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Fix session removal on shutdown

2022-06-22T01:14:54+00:00

When the system is shutting down, iscsid is not running so we will not get a response to the ISCSI_ERR_INVALID_HOST error event. The system shutdown will then hang waiting on userspace to remove the session. This has libiscsi force the destruction of the session from the kernel when iscsi_host_remove() is called from a driver's shutdown callout. This fixes a regression added in qedi boot with commit d1f2ce77638d ("scsi: qedi: Fix host removal with running sessions") which made qedi use the common session removal function that waits on userspace instead of rolling its own kernel based removal. Link: https://lore.kernel.org/r/20220616222738.5722-7-michael.christie@oracle.com Fixes: d1f2ce77638d ("scsi: qedi: Fix host removal with running sessions") Tested-by: Nilesh Javali Reviewed-by: Lee Duncan Reviewed-by: Nilesh Javali Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Add helper to remove a session from the kernel

2022-06-22T01:14:54+00:00

During qedi shutdown we need to stop the iSCSI layer from sending new nops as pings and from responding to target ones and make sure there is no running connection cleanups. Commit d1f2ce77638d ("scsi: qedi: Fix host removal with running sessions") converted the driver to use the libicsi helper to drive session removal, so the above issues could be handled. The problem is that during system shutdown iscsid will not be running so when we try to remove the root session we will hang waiting for userspace to reply. Add a helper that will drive the destruction of sessions like these during system shutdown. Link: https://lore.kernel.org/r/20220616222738.5722-5-michael.christie@oracle.com Tested-by: Nilesh Javali Reviewed-by: Nilesh Javali Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Make iscsi_unregister_transport() return void

2022-06-17T02:11:18+00:00

This function always returns 0. We can make it return void to simplify the code. Also, no caller ever checks the return value of this function. Link: https://lore.kernel.org/r/20220616080210.18531-1-mgurtovoy@nvidia.com Reviewed-by: Mike Christie Signed-off-by: Max Gurtovoy Signed-off-by: Martin K. Petersen

scsi: libsas: Introduce struct smp_rps_resp

2022-06-10T17:08:06+00:00

Similarly to sas report general and discovery responses, define the structure struct smp_rps_resp to handle SATA PHY report responses using a structure with a size that is exactly equal to the sas defined response size. With this change, struct smp_resp becomes unused and is removed. Link: https://lore.kernel.org/r/20220609022456.409087-4-damien.lemoal@opensource.wdc.com Reviewed-by: John Garry Signed-off-by: Damien Le Moal Signed-off-by: Martin K. Petersen

scsi: libsas: Introduce struct smp_rg_resp

2022-06-10T17:08:06+00:00

When compiling with gcc 12, several warnings are thrown by gcc when compiling drivers/scsi/libsas/sas_expander.c, e.g.: In function ‘sas_get_ex_change_count’, inlined from ‘sas_find_bcast_dev’ at drivers/scsi/libsas/sas_expander.c:1816:8: drivers/scsi/libsas/sas_expander.c:1781:20: warning: array subscript ‘struct smp_resp[0]’ is partly outside array bounds of ‘unsigned char[32]’ [-Warray-bounds] 1781 | if (rg_resp->result != SMP_RESP_FUNC_ACC) { | ~~~~~~~^~~~~~~~ This is due to the use of the struct smp_resp to aggregate all possible response types using a union but allocating a response buffer with a size exactly equal to the size of the response type needed. This leads to access to fields of struct smp_resp from an allocated memory area that is smaller than the size of struct smp_resp. Fix this by defining struct smp_rg_resp for sas report general responses. Link: https://lore.kernel.org/r/20220609022456.409087-3-damien.lemoal@opensource.wdc.com Reviewed-by: John Garry Signed-off-by: Damien Le Moal Signed-off-by: Martin K. Petersen

scsi: libsas: Introduce struct smp_disc_resp

2022-06-10T17:08:06+00:00

When compiling with gcc 12, several warnings are thrown by gcc when compiling drivers/scsi/libsas/sas_expander.c, e.g.: In function ‘sas_get_phy_change_count’, inlined from ‘sas_find_bcast_phy.constprop’ at drivers/scsi/libsas/sas_expander.c:1737:9: drivers/scsi/libsas/sas_expander.c:1697:39: warning: array subscript ‘struct smp_resp[0]’ is partly outside array bounds of ‘unsigned char[56]’ [-Warray-bounds] 1697 | *pcc = disc_resp->disc.change_count; | ~~~~~~~~~~~~~~~^~~~~~~~~~~~~ This is due to the use of the struct smp_resp to aggregate all possible response types using a union but allocating a response buffer with a size exactly equal to the size of the response type needed. This leads to access to fields of struct smp_resp from an allocated memory area that is smaller than the size of struct smp_resp. Fix this by defining struct smp_disc_resp for sas discovery operations. Since this structure and the generic struct smp_resp are identical for the little endian and big endian archs, move the definition of these structures at the end of include/scsi/sas.h to avoid repeating their definition. Link: https://lore.kernel.org/r/20220609022456.409087-2-damien.lemoal@opensource.wdc.com Reviewed-by: John Garry Signed-off-by: Damien Le Moal Signed-off-by: Martin K. Petersen