| Message ID | 20210125191122.345858-1-dgilbert@interlog.com |
|---|---|
| Headers | show |
| Series | sg: add v4 interface | expand |
Douglas, > Changes since v14 (sent to linux-scsi list on 20210124) > - two fixes based on report from Dan Carpenter and kernel test > robot > - fix Johannes Thumshirn's email address > - separate patch issued on fio to add 'hipri' option to its sg > engine. Enables fio to test new sg driver blk_poll() support > > Changes since v13 (sent to linux-scsi list on 20210113) > - fix obscure compile error reported by "kernel test robot > <lkp@intel.com>" > - harden code around blk_poll() invocation; needed based on > fio testing > - remove SG_FFD_MMAP_CALLED bit code after Hannes Reinecke pointed > out it was redundant Please send incremental fixes for the patches I already applied. -- Martin K. Petersen Oracle Linux Engineering
This patchset is the first stage of a two stage rewrite of the scsi generic (sg) driver. The main goal of the first stage is to introduce the sg v4 interface that uses 'struct sg_io_v4' as well as keeping and modernizing the sg v3 interface (based on 'struct sg_io_hdr'). The async interface formerly requiring the use of write() and read() system calls now have ioctl(SG_IOSUBMIT) and ioctl(SG_IORECEIVE) replacements. A recent patch added support for blk_poll() and requests that have REQ_HIPRI set. The blk_poll() additions are in patch 44 and will compile. However, to use those additions one or more SCSI LLDs are needed that support mq_poll(). For those look to a patchset from Kashyap Desai called "[PATCH v1 0/3] io_uring iopoll in scsi layer". This patchset allows 'iopoll' requests to be issued without io_uring. iopoll and blk_poll() can be considered synonymous. One further note, an _async_ interface to blk_poll() is being proposed. For documentation see: http://sg.danny.cz/sg/sg_v40.html for more details. If accessing http pages is a problem, a temporary rendering of this page can be found here: https://doug-gilbert.github.io/sg_v40.html This patchset is against Martin Petersen's 5.12/scsi-queue branch. Changes since v14 (sent to linux-scsi list on 20210124) - two fixes based on report from Dan Carpenter and kernel test robot - fix Johannes Thumshirn's email address - separate patch issued on fio to add 'hipri' option to its sg engine. Enables fio to test new sg driver blk_poll() support Changes since v13 (sent to linux-scsi list on 20210113) - fix obscure compile error reported by "kernel test robot <lkp@intel.com>" - harden code around blk_poll() invocation; needed based on fio testing - remove SG_FFD_MMAP_CALLED bit code after Hannes Reinecke pointed out it was redundant Changes since v12 (sent to linux-scsi list on 20201115) - add blk_poll() support, prefix that patch's subject with 'RFC' Changes since v11 (sent to linux-scsi list on 20201014) - no author originated changes since v11 - port from lk 5.9.0-rc1 to lk 5.10.0-rc1 picks up a change to the import_iovec() which requires a change to patch 25/44 - only publish this cover letter and v12 of patch 25/44 to the linux-scsi list. The other 43 patches remain as published on 20201014. Changes since v10 (sent to linux-scsi list on 20200823) - unchanged: 0001 to 0009, 0010 to 0017 - rename sg_add_req() to sg_setup_req() [0010] - patches 40,41,42 and 43 are new, see their commit messages - remove SG_RS_RCV_DONE request state leaving 3.5 states [the 0.5 state is SG_RS_BUSY] - rework sg_rq_chg_state() code that enforces request state changes and associated xarray marks - track lowest used and unused indexes in the request arrays so iterations over the request xarray are efficient. This is a significant saving when the iodepth queue length is large Changes since v9 (sent to linux-scsi list on 20200421) - rebase on MKP's 5.10/scsi-queue branch - remove some master/slave terminology that had bled in from the part 2 patchset - change sg_request::start_ns type from ktime_t to u64 - pick up several error path correction fixes applied to the sg driver by other authors Changes since v8 (sent to linux-scsi list on 20200301) - add new patch to ignore the /proc/scsi/sg/allow_dio setting. Now direct IO will be attempted whenever the SG_FLAG_DIRECT_IO flag is given - add new patch to track mmap_sz from previous mmap() call. Allows catching mmap-ed requests that exceed that value - change warning about using the v3 interface with the write() system call from WARN_ONCE() to pr_warn_once() - remove __KERNEL__ conditionals in include/scsi/sg.h - change struct sg_fd::start_ns from u64 to ktime_t type - introduce a new small sg_rq_state_mul2arr array to avoid a multiplication at runtime in the state machine engine - tweak mempool introduced in v7 for sense buffers - rework sg_mk_sgat() to better handle low memory situations; similar work on sg_remove_sgat_helper() Changes since v7 (sent to linux-scsi list on 20200227) - improve direct IO code, remove the SG_FRQ_DIO_IN_USE sg_request::frq_bm flag as it is no longer needed - simplify state changing code. Many state changes (rq_st) do not need changes to the xarray "marks"; only lock those that do (reviewer queried the locking) - remove some misplaced likely()/unlikely() macros. They are gathered together in a separate patch (in a second patchset) - change a cast that the kbuild robot complained about. It also flagged a stack size problem in sg_ioctl_common() for reasons not given nor obvious. That function (and its parents) declare only simple scalars on the stack. - add 'Reviewed-by' where appropriate Changes since v6 (sent to linux-scsi list on 20200112) - based on Martin Petersen's 5.7/scsi-queue branch in his linux-scsi repository - major work on mmap support: when mmap(2) is used the reserve request scatter gather list is rebuilt to have order=0 elements (i.e. each is PAGE_SIZE bytes). - address one kbuild robot issue: add include defining size_t - nearly all patches that have been reviewed have been changed, usually in minor ways. Those patches have "***" before the "Reviewed-by" line. Changes since v5 to v1 in earlier patchsets - for example: the v10 patchset sent to linux-scsi on 20200823 Douglas Gilbert (45): sg: move functions around sg: remove typedefs, type+formatting cleanup sg: sg_log and is_enabled sg: rework sg_poll(), minor changes sg: bitops in sg_device sg: make open count an atomic sg: move header to uapi section sg: speed sg_poll and sg_get_num_waiting sg: sg_allow_if_err_recovery and renames sg: improve naming sg: change rwlock to spinlock sg: ioctl handling sg: split sg_read sg: sg_common_write add structure for arguments sg: rework sg_vma_fault sg: rework sg_mmap sg: replace sg_allow_access sg: rework scatter gather handling sg: introduce request state machine sg: sg_find_srp_by_id sg: sg_fill_request_element sg: printk change %p to %pK sg: xarray for fds in device sg: xarray for reqs in fd sg: replace rq array with xarray sg: sense buffer rework sg: add sg v4 interface support sg: rework debug info sg: add 8 byte SCSI LUN to sg_scsi_id sg: expand sg_comm_wr_t sg: add sg_iosubmit_v3 and sg_ioreceive_v3 ioctls sg: add some __must_hold macros sg: move procfs objects to avoid forward decls sg: protect multiple receivers sg: first debugfs support sg: rework mmap support sg: defang allow_dio sg: warn v3 write system call users sg: add mmap_sz tracking sg: remove rcv_done request state sg: track lowest inactive and await indexes sg: remove unit attention check for device changed sg: no_dxfer: move to/from kernel buffers sg: add blk_poll support sg: bump version to 4.0.12 drivers/scsi/sg.c | 5389 +++++++++++++++++++++++++++------------- include/scsi/sg.h | 273 +- include/uapi/scsi/sg.h | 375 +++ 3 files changed, 4112 insertions(+), 1925 deletions(-) create mode 100644 include/uapi/scsi/sg.h