20 Mar, 2013

1 commit

  • This patch bumps the default FILEIO backend FD_MAX_SECTORS value from
    1024 -> 2048 in order to allow block_size=512 to handle 1M sized I/Os.

    The current default rejects I/Os larger than 512K in sbc_parse_cdb():

    [12015.915146] SCSI OP 2ah with too big sectors 1347 exceeds backend
    hw_max_sectors: 1024
    [12015.977744] SCSI OP 2ah with too big sectors 2048 exceeds backend
    hw_max_sectors: 1024

    This issue is present in >= v3.5 based kernels, introduced after the
    removal of se_task logic.

    Reported-by: Viljami Ilola
    Cc:
    Signed-off-by: Nicholas Bellinger

    Nicholas Bellinger
     

07 Nov, 2012

1 commit

  • Simplify the code a lot by killing the superflous struct se_subsystem_dev.
    Instead se_device is allocated early on by the backend driver, which allocates
    it as part of its own per-device structure, borrowing the scheme that is for
    example used for inode allocation.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Nicholas Bellinger

    Christoph Hellwig
     

03 Oct, 2012

1 commit

  • This patch re-adds the ability to optionally run in buffered FILEIO mode
    (eg: w/o O_DSYNC) for device backends in order to once again use the
    Linux buffered cache as a write-back storage mechanism.

    This logic was originally dropped with mainline v3.5-rc commit:

    commit a4dff3043c231d57f982af635c9d2192ee40e5ae
    Author: Nicholas Bellinger
    Date: Wed May 30 16:25:41 2012 -0700

    target/file: Use O_DSYNC by default for FILEIO backends

    This difference with this patch is that fd_create_virtdevice() now
    forces the explicit setting of emulate_write_cache=1 when buffered FILEIO
    operation has been enabled.

    (v2: Switch to FDBD_HAS_BUFFERED_IO_WCE + add more detailed
    comment as requested by hch)

    Reported-by: Ferry
    Cc: Christoph Hellwig
    Cc:
    Signed-off-by: Nicholas Bellinger

    Nicholas Bellinger
     

03 Jun, 2012

1 commit

  • Convert to use O_DSYNC for all cases at FILEIO backend creation time to
    avoid the extra syncing of pure timestamp updates with legacy O_SYNC during
    default operation as recommended by hch. Continue to do this independently of
    Write Cache Enable (WCE) bit, as WCE=0 is currently the default for all backend
    devices and enabled by user on per device basis via attrib/emulate_write_cache.

    This patch drops the now unnecessary fd_buffered_io= token usage that was
    originally signalling when to explictly disable O_SYNC at backend creation
    time for buffered I/O operation. This can end up being dangerous for a number
    of reasons during physical node failure, so go ahead and drop this option
    for now when O_DSYNC is used as the default.

    Also allow explict FUA WRITEs -> vfs_fsync_range() call to function in
    fd_execute_cmd() independently of WCE bit setting.

    Reported-by: Christoph Hellwig
    Cc: Linus Torvalds
    Cc:
    Signed-off-by: Nicholas Bellinger

    Nicholas Bellinger
     

07 May, 2012

1 commit

  • We can use struct se_cmd for everything it did. Make sure to pass the S/G
    list and data direction to the execution function to ease adding back BIDI
    support later on.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Nicholas Bellinger

    Christoph Hellwig
     

24 Oct, 2011

1 commit


22 Jul, 2011

2 commits

  • This patch contains the squashed version of forth round series cleanups
    from Andy and Christoph following the post heavy lifting in the preceeding:
    'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
    changes. This also includes a conversion of target core and the v3.0
    mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
    CONFIG_DYNAMIC_DEBUG infrastructure!

    These have been squashed into this third and final round for v3.1.

    target: Remove ifdeffed code in t_g_process_write
    target: Remove direct ramdisk code
    target: Rename task_sg_num to task_sg_nents
    target: Remove custom debug macros for pr_debug. Use pr_err().
    target: Remove custom debug macros in mainline fabrics
    target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
    target: Remove transport do_se_mem_map callback
    target: Further simplify transport_free_pages
    target: Redo task allocation return value handling
    target: Remove extra parentheses
    target: change alloc_task call to take *cdb, not *cmd

    (nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)

    Signed-off-by: Andy Grover
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Nicholas Bellinger

    Andy Grover
     
  • This patch contains the squashed version of a number of cleanups and
    minor fixes from Andy's initial series (round 1) for target core this
    past spring. The condensed log looks like:

    target: use errno values instead of returning -1 for everything
    target: Rename transport_calc_sg_num to transport_init_task_sg
    target: Fix leak in error path in transport_init_task_sg
    target/pscsi: Remove pscsi_get_sh() usage
    target: Make two runtime checks into WARN_ONs
    target: Remove hba queue depth and convert to spin_lock_irq usage
    target: dev->dev_status_queue_obj is unused
    target: Make struct se_queue_req.cmd type struct se_cmd *
    target: Remove __transport_get_qr_from_queue()
    target: Rename se_dev->g_se_dev_list to se_dev_node
    target: Remove struct se_global
    target: Simplify scsi mib index table code
    target: Make dev_queue_obj a member of se_device instead of a pointer
    target: remove extraneous returns at end of void functions
    target: Ensure transport_dump_vpd_ident_type returns null-terminated str
    target: Function pointers don't need to use '&' to be assigned
    target: Fix comment in __transport_execute_tasks()
    target: Misc style cleanups
    target: rename struct pr_reservation_template to pr_reservation
    target: Remove #defines that just perform indirection
    target: Inline transport_get_task_from_execute_queue()
    target: Minor header comment fixes

    Signed-off-by: Andy Grover
    Signed-off-by: Nicholas Bellinger

    Andy Grover
     

15 Jan, 2011

1 commit

  • LIO target is a full featured in-kernel target framework with the
    following feature set:

    High-performance, non-blocking, multithreaded architecture with SIMD
    support.

    Advanced SCSI feature set:

    * Persistent Reservations (PRs)
    * Asymmetric Logical Unit Assignment (ALUA)
    * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
    * Full Error Recovery (ERL=0,1,2)
    * Active/active task migration and session continuation (ERL=2)
    * Thin LUN provisioning (UNMAP and WRITE_SAMExx)

    Multiprotocol target plugins

    Storage media independence:

    * Virtualization of all storage media; transparent mapping of IO to LUNs
    * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
    * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.

    Standards compliance:

    * Full compliance with IETF (RFC 3720)
    * Full implementation of SPC-4 PRs and ALUA

    Significant code cleanups done by Christoph Hellwig.

    [jejb: fix up for new block bdev exclusive interface. Minor fixes from
    Randy Dunlap and Dan Carpenter.]
    Signed-off-by: Nicholas A. Bellinger
    Signed-off-by: James Bottomley

    Nicholas Bellinger