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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-04 12:19:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-04 12:19:44 -0700
commit8d5e72dfdf0fa29a21143fd72746c6f43295ce9f (patch)
treecd51765801a1ad27a6db13809e00085b2677d351 /Documentation
parent2bd80401743568ced7d303b008ae5298ce77e695 (diff)
parente7731da36f107e87b0ea137265ebcc991972e14c (diff)
downloadlinux-8d5e72dfdf0fa29a21143fd72746c6f43295ce9f.tar.bz2
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley: "This update includes the usual round of major driver updates (hisi_sas, ufs, fnic, cxlflash, be2iscsi, ipr, stex). There's also the usual amount of cosmetic and spelling stuff" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (155 commits) scsi: qla4xxx: fix spelling mistake: "Tempalate" -> "Template" scsi: stex: make S6flag static scsi: mac_esp: fix to pass correct device identity to free_irq() scsi: aacraid: pci_alloc_consistent() failures on ARM64 scsi: ufs: make ufshcd_get_lists_status() register operation obvious scsi: ufs: use MASK_EE_STATUS scsi: mac_esp: Replace bogus memory barrier with spinlock scsi: fcoe: make fcoe_e_d_tov and fcoe_r_a_tov static scsi: sd_zbc: Do not write lock zones for reset scsi: sd_zbc: Remove superfluous assignments scsi: sd: sd_zbc: Rename sd_zbc_setup_write_cmnd scsi: Improve scsi_get_sense_info_fld scsi: sd: Cleanup sd_done sense data handling scsi: sd: Improve sd_completed_bytes scsi: sd: Fix function descriptions scsi: mpt3sas: remove redundant wmb scsi: mpt: Move scsi_remove_host() out of mptscsih_remove_host() scsi: sg: reset 'res_in_use' after unlinking reserved array scsi: mvumi: remove code handling zero scsi_sg_count(scmd) case scsi: fusion: fix spelling mistake: "Persistancy" -> "Persistency" ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/powerpc/cxlflash.txt5
-rw-r--r--Documentation/scsi/scsi_eh.txt30
2 files changed, 17 insertions, 18 deletions
diff --git a/Documentation/powerpc/cxlflash.txt b/Documentation/powerpc/cxlflash.txt
index 6d9a2ed32cad..66b4496d6619 100644
--- a/Documentation/powerpc/cxlflash.txt
+++ b/Documentation/powerpc/cxlflash.txt
@@ -239,6 +239,11 @@ DK_CXLFLASH_USER_VIRTUAL
resource handle that is provided is already referencing provisioned
storage. This is reflected by the last LBA being a non-zero value.
+ When a LUN is accessible from more than one port, this ioctl will
+ return with the DK_CXLFLASH_ALL_PORTS_ACTIVE return flag set. This
+ provides the user with a hint that I/O can be retried in the event
+ of an I/O error as the LUN can be reached over multiple paths.
+
DK_CXLFLASH_VLUN_RESIZE
-----------------------
This ioctl is responsible for resizing a previously created virtual
diff --git a/Documentation/scsi/scsi_eh.txt b/Documentation/scsi/scsi_eh.txt
index 37eca00796ee..11e447bdb3a5 100644
--- a/Documentation/scsi/scsi_eh.txt
+++ b/Documentation/scsi/scsi_eh.txt
@@ -70,7 +70,7 @@ with the command.
scmd is requeued to blk queue.
- otherwise
- scsi_eh_scmd_add(scmd, 0) is invoked for the command. See
+ scsi_eh_scmd_add(scmd) is invoked for the command. See
[1-3] for details of this function.
@@ -103,13 +103,14 @@ function
eh_timed_out() callback did not handle the command.
Step #2 is taken.
- 2. If the host supports asynchronous completion (as indicated by the
- no_async_abort setting in the host template) scsi_abort_command()
- is invoked to schedule an asynchrous abort. If that fails
- Step #3 is taken.
+ 2. scsi_abort_command() is invoked to schedule an asynchrous abort.
+ Asynchronous abort are not invoked for commands which the
+ SCSI_EH_ABORT_SCHEDULED flag is set (this indicates that the command
+ already had been aborted once, and this is a retry which failed),
+ or when the EH deadline is expired. In these case Step #3 is taken.
- 2. scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD) is invoked for the
- command. See [1-3] for more information.
+ 3. scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD) is invoked for the
+ command. See [1-4] for more information.
[1-3] Asynchronous command aborts
@@ -124,16 +125,13 @@ function
scmds enter EH via scsi_eh_scmd_add(), which does the following.
- 1. Turns on scmd->eh_eflags as requested. It's 0 for error
- completions and SCSI_EH_CANCEL_CMD for timeouts.
+ 1. Links scmd->eh_entry to shost->eh_cmd_q
- 2. Links scmd->eh_entry to shost->eh_cmd_q
+ 2. Sets SHOST_RECOVERY bit in shost->shost_state
- 3. Sets SHOST_RECOVERY bit in shost->shost_state
+ 3. Increments shost->host_failed
- 4. Increments shost->host_failed
-
- 5. Wakes up SCSI EH thread if shost->host_busy == shost->host_failed
+ 4. Wakes up SCSI EH thread if shost->host_busy == shost->host_failed
As can be seen above, once any scmd is added to shost->eh_cmd_q,
SHOST_RECOVERY shost_state bit is turned on. This prevents any new
@@ -249,7 +247,6 @@ scmd->allowed.
1. Error completion / time out
ACTION: scsi_eh_scmd_add() is invoked for scmd
- - set scmd->eh_eflags
- add scmd to shost->eh_cmd_q
- set SHOST_RECOVERY
- shost->host_failed++
@@ -263,7 +260,6 @@ scmd->allowed.
3. scmd recovered
ACTION: scsi_eh_finish_cmd() is invoked to EH-finish scmd
- - clear scmd->eh_eflags
- scsi_setup_cmd_retry()
- move from local eh_work_q to local eh_done_q
LOCKING: none
@@ -456,8 +452,6 @@ except for #1 must be implemented by eh_strategy_handler().
- shost->host_failed is zero.
- - Each scmd's eh_eflags field is cleared.
-
- Each scmd is in such a state that scsi_setup_cmd_retry() on the
scmd doesn't make any difference.