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authorLinus Torvalds <torvalds@linux-foundation.org>2015-05-31 11:31:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-05-31 11:31:42 -0700
commitdae8f283bf30738593f6d2a4623945c5e6d7794e (patch)
treef4ef01f19ff8cbdae0eaac61f12236ed5e9f297d /Documentation
parent30a5f11896a26a345e934e18e9a62c714bc1ceed (diff)
parentb2feda4feb1b0ea74c0916b4a35b038bbfef9c82 (diff)
downloadlwn-dae8f283bf30738593f6d2a4623945c5e6d7794e.tar.gz
lwn-dae8f283bf30738593f6d2a4623945c5e6d7794e.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger: "These are mostly minor fixes, with the exception of the following that address fall-out from recent v4.1-rc1 changes: - regression fix related to the big fabric API registration changes and configfs_depend_item() usage, that required cherry-picking one of HCH's patches from for-next to address the issue for v4.1 code. - remaining TCM-USER -v2 related changes to enforce full CDB passthrough from Andy + Ilias. Also included is a target_core_pscsi driver fix from Andy that addresses a long standing issue with a Scsi_Host reference being leaked on PSCSI device shutdown" * git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: iser-target: Fix error path in isert_create_pi_ctx() target: Use a PASSTHROUGH flag instead of transport_types target: Move passthrough CDB parsing into a common function target/user: Only support full command pass-through target/user: Update example code for new ABI requirements target/pscsi: Don't leak scsi_host if hba is VIRTUAL_HOST target: Fix se_tpg_tfo->tf_subsys regression + remove tf_subsystem target: Drop signal_pending checks after interruptible lock acquire target: Add missing parentheses target: Fix bidi command handling target/user: Disallow full passthrough (pass_level=0) ISCSI: fix minor memory leak
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/target/tcmu-design.txt33
1 files changed, 7 insertions, 26 deletions
diff --git a/Documentation/target/tcmu-design.txt b/Documentation/target/tcmu-design.txt
index 43e94ea6d2ca..263b907517ac 100644
--- a/Documentation/target/tcmu-design.txt
+++ b/Documentation/target/tcmu-design.txt
@@ -15,8 +15,7 @@ Contents:
a) Discovering and configuring TCMU uio devices
b) Waiting for events on the device(s)
c) Managing the command ring
-3) Command filtering and pass_level
-4) A final note
+3) A final note
TCM Userspace Design
@@ -324,7 +323,7 @@ int handle_device_events(int fd, void *map)
/* Process events from cmd ring until we catch up with cmd_head */
while (ent != (void *)mb + mb->cmdr_off + mb->cmd_head) {
- if (tcmu_hdr_get_op(&ent->hdr) == TCMU_OP_CMD) {
+ if (tcmu_hdr_get_op(ent->hdr.len_op) == TCMU_OP_CMD) {
uint8_t *cdb = (void *)mb + ent->req.cdb_off;
bool success = true;
@@ -339,8 +338,12 @@ int handle_device_events(int fd, void *map)
ent->rsp.scsi_status = SCSI_CHECK_CONDITION;
}
}
+ else if (tcmu_hdr_get_op(ent->hdr.len_op) != TCMU_OP_PAD) {
+ /* Tell the kernel we didn't handle unknown opcodes */
+ ent->hdr.uflags |= TCMU_UFLAG_UNKNOWN_OP;
+ }
else {
- /* Do nothing for PAD entries */
+ /* Do nothing for PAD entries except update cmd_tail */
}
/* update cmd_tail */
@@ -360,28 +363,6 @@ int handle_device_events(int fd, void *map)
}
-Command filtering and pass_level
---------------------------------
-
-TCMU supports a "pass_level" option with valid values of 0 or 1. When
-the value is 0 (the default), nearly all SCSI commands received for
-the device are passed through to the handler. This allows maximum
-flexibility but increases the amount of code required by the handler,
-to support all mandatory SCSI commands. If pass_level is set to 1,
-then only IO-related commands are presented, and the rest are handled
-by LIO's in-kernel command emulation. The commands presented at level
-1 include all versions of:
-
-READ
-WRITE
-WRITE_VERIFY
-XDWRITEREAD
-WRITE_SAME
-COMPARE_AND_WRITE
-SYNCHRONIZE_CACHE
-UNMAP
-
-
A final note
------------