linux.git/drivers/target/target_core_device.c, branch v3.13

target/file: Update hw_max_sectors based on current block_size

2013-12-19T08:18:54+00:00

This patch allows FILEIO to update hw_max_sectors based on the current
max_bytes_per_io.  This is required because vfs_[writev,readv]() can accept
a maximum of 2048 iovecs per call, so the enforced hw_max_sectors really
needs to be calculated based on block_size.

This addresses a >= v3.5 bug where block_size=512 was rejecting > 1M
sized I/O requests, because FD_MAX_SECTORS was hardcoded to 2048 for
the block_size=4096 case.

(v2: Use max_bytes_per_io instead of ->update_hw_max_sectors)

Reported-by: Henrik Goldman 
Cc:  #3.5+
Signed-off-by: Nicholas Bellinger

target core: rename (ex,im)plict -> (ex,im)plicit

2013-11-20T19:24:40+00:00

Signed-off-by: Hannes Reinecke 
Signed-off-by: Nicholas Bellinger

target: Convert se_device statistics to atomic_long_t

2013-11-14T02:34:55+00:00

This patch converts the handful of se_device statistics to type
atomic_long_t, instead of using se_device->stats_lock when
incrementing these values.

More importantly, go ahead and drop the spinlock usage within
transport_lookup_cmd_lun() fast-path code.

Signed-off-by: Nicholas Bellinger

target: Add per device xcopy_lun for copy offload I/O

2013-11-08T21:13:38+00:00

This patch adds a se_device->xcopy_lun that is used for local
copy offload I/O, instead of allocating + initializing a pseudo
se_lun for each received EXTENDED_COPY operation.

Also, move declaration of struct se_lun + struct se_port_stat_grps
ahead of struct se_device.

Signed-off-by: Nicholas Bellinger

target: Add percpu refcounting for se_lun access

2013-11-07T22:24:52+00:00

This patch adds percpu refcounting for se_lun access that allows the
association of an se_lun + se_cmd in transport_lookup_cmd_lun() to
occur without an extra list_head for tracking outstanding I/O during
se_lun shutdown.

This effectively changes se_lun shutdown logic to wait for outstanding
I/O percpu references to complete in transport_lun_remove_cmd() using
se_lun->lun_ref_comp, instead of explicitly draining the per se_lun
command list and waiting for individual se_cmd descriptor processing
to complete.

Cc: Kent Overstreet 
Signed-off-by: Nicholas Bellinger

target: Update copyright ownership/year information to 2013

2013-09-11T03:23:36+00:00

Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.

Signed-off-by: Nicholas Bellinger

target: Add Third Party Copy (3PC) bit in INQUIRY response

2013-09-10T23:48:46+00:00

This patch adds the Third Party Copy (3PC) bit to signal support
for EXTENDED_COPY within standard inquiry response data.

Also add emulate_3pc device attribute in configfs (enabled by default)
to allow the exposure of this bit to be disabled, if necessary.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: Roland Dreier 
Cc: Zach Brown 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Add global device list for EXTENDED_COPY

2013-09-10T23:48:40+00:00

EXTENDED_COPY needs to be able to search a global list of devices
based on NAA WWN device identifiers, so add a simple g_device_list
protected by g_device_mutex.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: Roland Dreier 
Cc: Zach Brown 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Add support for COMPARE_AND_WRITE emulation

2013-09-10T23:41:59+00:00

This patch adds support for COMPARE_AND_WRITE emulation on a per block
basis.  This logic is used as an atomic test and set primative currently
used by VMWare ESX VAAI for performing array side locking of individual
VMFS extent ownership.

This includes the COMPARE_AND_WRITE CDB parsing within sbc_parse_cdb(),
and does the majority of the work within the compare_and_write_callback()
to perform the verify instance user data comparision, and subsequent
write instance user data I/O submission upon a successfull comparision.

The synchronization is enforced by se_device->caw_sem, that is obtained
before the initial READ I/O submission in sbc_compare_and_write().  The
mutex is then released upon MISCOMPARE in compare_and_write_callback(),
or upon WRITE instance user-data completion in compare_and_write_post().

The implementation currently assumes a single logical block (NoLB=1).

v4 changes:
 - Explicitly clear cmd->transport_complete_callback for two failure
   cases in sbc_compare_and_write() in order to avoid double unlock
   of ->caw_sem in compare_and_write_callback() (Dan Carpenter)

v3 changes:
 - Convert se_device->caw_mutex to ->caw_sem

v2 changes:
 - Set SCF_COMPARE_AND_WRITE and cmd->execute_cmd() to
   sbc_compare_and_write() during setup in sbc_parse_cdb()
 - Use sbc_compare_and_write() for initial READ submission with
   DMA_FROM_DEVICE
 - Reset cmd->execute_cmd() to sbc_execute_rw() for write instance
   user-data in compare_and_write_callback()
 - Drop SCF_BIDI command flag usage
 - Set TRANSPORT_PROCESSING + transport_state flags before write
   instance submission, and convert to __target_execute_cmd()
 - Prevent sbc_get_size() from being being called twice to
   generate incorrect size in sbc_parse_cdb()
 - Enforce se_device->caw_mutex synchronization between initial
   READ I/O submission, and final WRITE I/O completion.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Add MAXIMUM COMPARE AND WRITE LENGTH in Block Limits VPD

2013-09-09T21:29:35+00:00

This patch adds the MAXIMUM COMPARE AND WRITE LENGTH bit, currently
hardcoded to a single logical block (NoLB=1) within the Block Limits
VPD in spc_emulate_evpd_b0().

Also add emulate_caw device attribute in configfs (enabled by default)
to allow the exposure of this bit to be disabled, if necessary.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger