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freebsd-skq/sys/cam/ctl/ctl_backend_block.c
Kenneth D. Merry 2a2443d833 Quiet some clang warnings when compiling CTL. 
ctl_error.c,
ctl_error.h:	Take out the ctl_sense_format enumeration, and use
		scsi_sense_data_type instead.

		Remove ctl_get_sense_format() and switch ctl_build_ua()
		over to using scsi_sense_data_type.

ctl_backend_ramdisk.c,
ctl_backend_block.c:
		Use C99 structure initializers instead of GNU initializers.

ctl.c:		Switch over to using the SCSI sense format enumeration
		instead of the CTL-specific enumeration.

Submitted by:	dim (partially)
MFC after:	1 month
2012-01-19 18:42:03 +00:00

2214 lines
57 KiB
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/*-
* Copyright (c) 2003 Silicon Graphics International Corp.
* Copyright (c) 2009-2011 Spectra Logic Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend_block.c#5 $
*/
/*
* CAM Target Layer driver backend for block devices.
*
* Author: Ken Merry <ken@FreeBSD.org>
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <opt_kdtrace.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/kthread.h>
#include <sys/bio.h>
#include <sys/fcntl.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/ioccom.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/endian.h>
#include <sys/uio.h>
#include <sys/buf.h>
#include <sys/taskqueue.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/mount.h>
#include <sys/disk.h>
#include <sys/fcntl.h>
#include <sys/filedesc.h>
#include <sys/proc.h>
#include <sys/pcpu.h>
#include <sys/module.h>
#include <sys/sdt.h>
#include <sys/devicestat.h>
#include <sys/sysctl.h>
#include <geom/geom.h>
#include <cam/cam.h>
#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_da.h>
#include <cam/ctl/ctl_io.h>
#include <cam/ctl/ctl.h>
#include <cam/ctl/ctl_backend.h>
#include <cam/ctl/ctl_frontend_internal.h>
#include <cam/ctl/ctl_ioctl.h>
#include <cam/ctl/ctl_scsi_all.h>
#include <cam/ctl/ctl_error.h>
/*
* The idea here is that we'll allocate enough S/G space to hold a 16MB
* I/O. If we get an I/O larger than that, we'll reject it.
*/
#define CTLBLK_MAX_IO_SIZE (16 * 1024 * 1024)
#define CTLBLK_MAX_SEGS (CTLBLK_MAX_IO_SIZE / MAXPHYS) + 1
#ifdef CTLBLK_DEBUG
#define DPRINTF(fmt, args...) \
printf("cbb(%s:%d): " fmt, __FUNCTION__, __LINE__, ##args)
#else
#define DPRINTF(fmt, args...) do {} while(0)
#endif
SDT_PROVIDER_DEFINE(cbb);
typedef enum {
CTL_BE_BLOCK_LUN_UNCONFIGURED = 0x01,
CTL_BE_BLOCK_LUN_CONFIG_ERR = 0x02,
CTL_BE_BLOCK_LUN_WAITING = 0x04,
CTL_BE_BLOCK_LUN_MULTI_THREAD = 0x08
} ctl_be_block_lun_flags;
typedef enum {
CTL_BE_BLOCK_NONE,
CTL_BE_BLOCK_DEV,
CTL_BE_BLOCK_FILE
} ctl_be_block_type;
struct ctl_be_block_devdata {
struct cdev *cdev;
struct cdevsw *csw;
int dev_ref;
};
struct ctl_be_block_filedata {
struct ucred *cred;
};
union ctl_be_block_bedata {
struct ctl_be_block_devdata dev;
struct ctl_be_block_filedata file;
};
struct ctl_be_block_io;
struct ctl_be_block_lun;
typedef void (*cbb_dispatch_t)(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio);
/*
* Backend LUN structure. There is a 1:1 mapping between a block device
* and a backend block LUN, and between a backend block LUN and a CTL LUN.
*/
struct ctl_be_block_lun {
struct ctl_block_disk *disk;
char lunname[32];
char *dev_path;
ctl_be_block_type dev_type;
struct vnode *vn;
union ctl_be_block_bedata backend;
cbb_dispatch_t dispatch;
cbb_dispatch_t lun_flush;
struct mtx lock;
uma_zone_t lun_zone;
uint64_t size_blocks;
uint64_t size_bytes;
uint32_t blocksize;
int blocksize_shift;
struct ctl_be_block_softc *softc;
struct devstat *disk_stats;
ctl_be_block_lun_flags flags;
STAILQ_ENTRY(ctl_be_block_lun) links;
struct ctl_be_lun ctl_be_lun;
struct taskqueue *io_taskqueue;
struct task io_task;
int num_threads;
STAILQ_HEAD(, ctl_io_hdr) input_queue;
STAILQ_HEAD(, ctl_io_hdr) config_write_queue;
STAILQ_HEAD(, ctl_io_hdr) datamove_queue;
};
/*
* Overall softc structure for the block backend module.
*/
struct ctl_be_block_softc {
STAILQ_HEAD(, ctl_be_block_io) beio_free_queue;
struct mtx lock;
int prealloc_beio;
int num_disks;
STAILQ_HEAD(, ctl_block_disk) disk_list;
int num_luns;
STAILQ_HEAD(, ctl_be_block_lun) lun_list;
};
static struct ctl_be_block_softc backend_block_softc;
/*
* Per-I/O information.
*/
struct ctl_be_block_io {
union ctl_io *io;
struct ctl_sg_entry sg_segs[CTLBLK_MAX_SEGS];
struct iovec xiovecs[CTLBLK_MAX_SEGS];
int bio_cmd;
int bio_flags;
int num_segs;
int num_bios_sent;
int num_bios_done;
int send_complete;
int num_errors;
struct bintime ds_t0;
devstat_tag_type ds_tag_type;
devstat_trans_flags ds_trans_type;
uint64_t io_len;
uint64_t io_offset;
struct ctl_be_block_softc *softc;
struct ctl_be_block_lun *lun;
STAILQ_ENTRY(ctl_be_block_io) links;
};
static int cbb_num_threads = 14;
TUNABLE_INT("kern.cam.ctl.block.num_threads", &cbb_num_threads);
SYSCTL_NODE(_kern_cam_ctl, OID_AUTO, block, CTLFLAG_RD, 0,
"CAM Target Layer Block Backend");
SYSCTL_INT(_kern_cam_ctl_block, OID_AUTO, num_threads, CTLFLAG_RW,
&cbb_num_threads, 0, "Number of threads per backing file");
static struct ctl_be_block_io *ctl_alloc_beio(struct ctl_be_block_softc *softc);
static void ctl_free_beio(struct ctl_be_block_io *beio);
static int ctl_grow_beio(struct ctl_be_block_softc *softc, int count);
#if 0
static void ctl_shrink_beio(struct ctl_be_block_softc *softc);
#endif
static void ctl_complete_beio(struct ctl_be_block_io *beio);
static int ctl_be_block_move_done(union ctl_io *io);
static void ctl_be_block_biodone(struct bio *bio);
static void ctl_be_block_flush_file(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio);
static void ctl_be_block_dispatch_file(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio);
static void ctl_be_block_flush_dev(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio);
static void ctl_be_block_dispatch_dev(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio);
static void ctl_be_block_cw_dispatch(struct ctl_be_block_lun *be_lun,
union ctl_io *io);
static void ctl_be_block_dispatch(struct ctl_be_block_lun *be_lun,
union ctl_io *io);
static void ctl_be_block_worker(void *context, int pending);
static int ctl_be_block_submit(union ctl_io *io);
static int ctl_be_block_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
int flag, struct thread *td);
static int ctl_be_block_open_file(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req);
static int ctl_be_block_open_dev(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req);
static int ctl_be_block_close(struct ctl_be_block_lun *be_lun);
static int ctl_be_block_open(struct ctl_be_block_softc *softc,
struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req);
static int ctl_be_block_create(struct ctl_be_block_softc *softc,
struct ctl_lun_req *req);
static int ctl_be_block_rm(struct ctl_be_block_softc *softc,
struct ctl_lun_req *req);
static void ctl_be_block_lun_shutdown(void *be_lun);
static void ctl_be_block_lun_config_status(void *be_lun,
ctl_lun_config_status status);
static int ctl_be_block_config_write(union ctl_io *io);
static int ctl_be_block_config_read(union ctl_io *io);
static int ctl_be_block_lun_info(void *be_lun, struct sbuf *sb);
int ctl_be_block_init(void);
static struct ctl_backend_driver ctl_be_block_driver =
{
.name = "block",
.flags = CTL_BE_FLAG_HAS_CONFIG,
.init = ctl_be_block_init,
.data_submit = ctl_be_block_submit,
.data_move_done = ctl_be_block_move_done,
.config_read = ctl_be_block_config_read,
.config_write = ctl_be_block_config_write,
.ioctl = ctl_be_block_ioctl,
.lun_info = ctl_be_block_lun_info
};
MALLOC_DEFINE(M_CTLBLK, "ctlblk", "Memory used for CTL block backend");
CTL_BACKEND_DECLARE(cbb, ctl_be_block_driver);
static struct ctl_be_block_io *
ctl_alloc_beio(struct ctl_be_block_softc *softc)
{
struct ctl_be_block_io *beio;
int count;
mtx_lock(&softc->lock);
beio = STAILQ_FIRST(&softc->beio_free_queue);
if (beio != NULL) {
STAILQ_REMOVE(&softc->beio_free_queue, beio,
ctl_be_block_io, links);
}
mtx_unlock(&softc->lock);
if (beio != NULL) {
bzero(beio, sizeof(*beio));
beio->softc = softc;
return (beio);
}
for (;;) {
count = ctl_grow_beio(softc, /*count*/ 10);
/*
* This shouldn't be possible, since ctl_grow_beio() uses a
* blocking malloc.
*/
if (count == 0)
return (NULL);
/*
* Since we have to drop the lock when we're allocating beio
* structures, it's possible someone else can come along and
* allocate the beio's we've just allocated.
*/
mtx_lock(&softc->lock);
beio = STAILQ_FIRST(&softc->beio_free_queue);
if (beio != NULL) {
STAILQ_REMOVE(&softc->beio_free_queue, beio,
ctl_be_block_io, links);
}
mtx_unlock(&softc->lock);
if (beio != NULL) {
bzero(beio, sizeof(*beio));
beio->softc = softc;
break;
}
}
return (beio);
}
static void
ctl_free_beio(struct ctl_be_block_io *beio)
{
struct ctl_be_block_softc *softc;
int duplicate_free;
int i;
softc = beio->softc;
duplicate_free = 0;
for (i = 0; i < beio->num_segs; i++) {
if (beio->sg_segs[i].addr == NULL)
duplicate_free++;
uma_zfree(beio->lun->lun_zone, beio->sg_segs[i].addr);
beio->sg_segs[i].addr = NULL;
}
if (duplicate_free > 0) {
printf("%s: %d duplicate frees out of %d segments\n", __func__,
duplicate_free, beio->num_segs);
}
mtx_lock(&softc->lock);
STAILQ_INSERT_TAIL(&softc->beio_free_queue, beio, links);
mtx_unlock(&softc->lock);
}
static int
ctl_grow_beio(struct ctl_be_block_softc *softc, int count)
{
int i;
for (i = 0; i < count; i++) {
struct ctl_be_block_io *beio;
beio = (struct ctl_be_block_io *)malloc(sizeof(*beio),
M_CTLBLK,
M_WAITOK | M_ZERO);
if (beio == NULL)
break;
bzero(beio, sizeof(*beio));
beio->softc = softc;
mtx_lock(&softc->lock);
STAILQ_INSERT_TAIL(&softc->beio_free_queue, beio, links);
mtx_unlock(&softc->lock);
}
return (i);
}
#if 0
static void
ctl_shrink_beio(struct ctl_be_block_softc *softc)
{
struct ctl_be_block_io *beio, *beio_tmp;
mtx_lock(&softc->lock);
STAILQ_FOREACH_SAFE(beio, &softc->beio_free_queue, links, beio_tmp) {
STAILQ_REMOVE(&softc->beio_free_queue, beio,
ctl_be_block_io, links);
free(beio, M_CTLBLK);
}
mtx_unlock(&softc->lock);
}
#endif
static void
ctl_complete_beio(struct ctl_be_block_io *beio)
{
union ctl_io *io;
int io_len;
io = beio->io;
if ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)
io_len = beio->io_len;
else
io_len = 0;
devstat_end_transaction(beio->lun->disk_stats,
/*bytes*/ io_len,
beio->ds_tag_type,
beio->ds_trans_type,
/*now*/ NULL,
/*then*/&beio->ds_t0);
ctl_free_beio(beio);
ctl_done(io);
}
static int
ctl_be_block_move_done(union ctl_io *io)
{
struct ctl_be_block_io *beio;
struct ctl_be_block_lun *be_lun;
#ifdef CTL_TIME_IO
struct bintime cur_bt;
#endif
beio = (struct ctl_be_block_io *)
io->io_hdr.ctl_private[CTL_PRIV_BACKEND].ptr;
be_lun = beio->lun;
DPRINTF("entered\n");
#ifdef CTL_TIME_IO
getbintime(&cur_bt);
bintime_sub(&cur_bt, &io->io_hdr.dma_start_bt);
bintime_add(&io->io_hdr.dma_bt, &cur_bt);
io->io_hdr.num_dmas++;
#endif
/*
* We set status at this point for read commands, and write
* commands with errors.
*/
if ((beio->bio_cmd == BIO_READ)
&& (io->io_hdr.port_status == 0)
&& ((io->io_hdr.flags & CTL_FLAG_ABORT) == 0)
&& ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE))
ctl_set_success(&io->scsiio);
else if ((io->io_hdr.port_status != 0)
&& ((io->io_hdr.flags & CTL_FLAG_ABORT) == 0)
&& ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE)) {
/*
* For hardware error sense keys, the sense key
* specific value is defined to be a retry count,
* but we use it to pass back an internal FETD
* error code. XXX KDM Hopefully the FETD is only
* using 16 bits for an error code, since that's
* all the space we have in the sks field.
*/
ctl_set_internal_failure(&io->scsiio,
/*sks_valid*/ 1,
/*retry_count*/
io->io_hdr.port_status);
}
/*
* If this is a read, or a write with errors, it is done.
*/
if ((beio->bio_cmd == BIO_READ)
|| ((io->io_hdr.flags & CTL_FLAG_ABORT) != 0)
|| ((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE)) {
ctl_complete_beio(beio);
return (0);
}
/*
* At this point, we have a write and the DMA completed
* successfully. We now have to queue it to the task queue to
* execute the backend I/O. That is because we do blocking
* memory allocations, and in the file backing case, blocking I/O.
* This move done routine is generally called in the SIM's
* interrupt context, and therefore we cannot block.
*/
mtx_lock(&be_lun->lock);
/*
* XXX KDM make sure that links is okay to use at this point.
* Otherwise, we either need to add another field to ctl_io_hdr,
* or deal with resource allocation here.
*/
STAILQ_INSERT_TAIL(&be_lun->datamove_queue, &io->io_hdr, links);
mtx_unlock(&be_lun->lock);
taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
return (0);
}
static void
ctl_be_block_biodone(struct bio *bio)
{
struct ctl_be_block_io *beio;
struct ctl_be_block_lun *be_lun;
union ctl_io *io;
beio = bio->bio_caller1;
be_lun = beio->lun;
io = beio->io;
DPRINTF("entered\n");
mtx_lock(&be_lun->lock);
if (bio->bio_error != 0)
beio->num_errors++;
beio->num_bios_done++;
/*
* XXX KDM will this cause WITNESS to complain? Holding a lock
* during the free might cause it to complain.
*/
g_destroy_bio(bio);
/*
* If the send complete bit isn't set, or we aren't the last I/O to
* complete, then we're done.
*/
if ((beio->send_complete == 0)
|| (beio->num_bios_done < beio->num_bios_sent)) {
mtx_unlock(&be_lun->lock);
return;
}
/*
* At this point, we've verified that we are the last I/O to
* complete, so it's safe to drop the lock.
*/
mtx_unlock(&be_lun->lock);
/*
* If there are any errors from the backing device, we fail the
* entire I/O with a medium error.
*/
if (beio->num_errors > 0) {
if (beio->bio_cmd == BIO_FLUSH) {
/* XXX KDM is there is a better error here? */
ctl_set_internal_failure(&io->scsiio,
/*sks_valid*/ 1,
/*retry_count*/ 0xbad2);
} else
ctl_set_medium_error(&io->scsiio);
ctl_complete_beio(beio);
return;
}
/*
* If this is a write or a flush, we're all done.
* If this is a read, we can now send the data to the user.
*/
if ((beio->bio_cmd == BIO_WRITE)
|| (beio->bio_cmd == BIO_FLUSH)) {
ctl_set_success(&io->scsiio);
ctl_complete_beio(beio);
} else {
io->scsiio.be_move_done = ctl_be_block_move_done;
io->scsiio.kern_data_ptr = (uint8_t *)beio->sg_segs;
io->scsiio.kern_data_len = beio->io_len;
io->scsiio.kern_total_len = beio->io_len;
io->scsiio.kern_rel_offset = 0;
io->scsiio.kern_data_resid = 0;
io->scsiio.kern_sg_entries = beio->num_segs;
io->io_hdr.flags |= CTL_FLAG_ALLOCATED | CTL_FLAG_KDPTR_SGLIST;
#ifdef CTL_TIME_IO
getbintime(&io->io_hdr.dma_start_bt);
#endif
ctl_datamove(io);
}
}
static void
ctl_be_block_flush_file(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio)
{
union ctl_io *io;
struct mount *mountpoint;
int vfs_is_locked, error, lock_flags;
DPRINTF("entered\n");
io = beio->io;
vfs_is_locked = VFS_LOCK_GIANT(be_lun->vn->v_mount);
(void) vn_start_write(be_lun->vn, &mountpoint, V_WAIT);
if (MNT_SHARED_WRITES(mountpoint)
|| ((mountpoint == NULL)
&& MNT_SHARED_WRITES(be_lun->vn->v_mount)))
lock_flags = LK_SHARED;
else
lock_flags = LK_EXCLUSIVE;
vn_lock(be_lun->vn, lock_flags | LK_RETRY);
binuptime(&beio->ds_t0);
devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
error = VOP_FSYNC(be_lun->vn, MNT_WAIT, curthread);
VOP_UNLOCK(be_lun->vn, 0);
vn_finished_write(mountpoint);
VFS_UNLOCK_GIANT(vfs_is_locked);
if (error == 0)
ctl_set_success(&io->scsiio);
else {
/* XXX KDM is there is a better error here? */
ctl_set_internal_failure(&io->scsiio,
/*sks_valid*/ 1,
/*retry_count*/ 0xbad1);
}
ctl_complete_beio(beio);
}
SDT_PROBE_DEFINE1(cbb, kernel, read, file_start, file_start, "uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, write, file_start, file_start, "uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, read, file_done, file_done,"uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, write, file_done, file_done, "uint64_t");
static void
ctl_be_block_dispatch_file(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio)
{
struct ctl_be_block_filedata *file_data;
union ctl_io *io;
struct uio xuio;
struct iovec *xiovec;
int vfs_is_locked, flags;
int error, i;
DPRINTF("entered\n");
file_data = &be_lun->backend.file;
io = beio->io;
flags = beio->bio_flags;
if (beio->bio_cmd == BIO_READ) {
SDT_PROBE(cbb, kernel, read, file_start, 0, 0, 0, 0, 0);
} else {
SDT_PROBE(cbb, kernel, write, file_start, 0, 0, 0, 0, 0);
}
bzero(&xuio, sizeof(xuio));
if (beio->bio_cmd == BIO_READ)
xuio.uio_rw = UIO_READ;
else
xuio.uio_rw = UIO_WRITE;
xuio.uio_offset = beio->io_offset;
xuio.uio_resid = beio->io_len;
xuio.uio_segflg = UIO_SYSSPACE;
xuio.uio_iov = beio->xiovecs;
xuio.uio_iovcnt = beio->num_segs;
xuio.uio_td = curthread;
for (i = 0, xiovec = xuio.uio_iov; i < xuio.uio_iovcnt; i++, xiovec++) {
xiovec->iov_base = beio->sg_segs[i].addr;
xiovec->iov_len = beio->sg_segs[i].len;
}
vfs_is_locked = VFS_LOCK_GIANT(be_lun->vn->v_mount);
if (beio->bio_cmd == BIO_READ) {
vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
binuptime(&beio->ds_t0);
devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
/*
* UFS pays attention to IO_DIRECT for reads. If the
* DIRECTIO option is configured into the kernel, it calls
* ffs_rawread(). But that only works for single-segment
* uios with user space addresses. In our case, with a
* kernel uio, it still reads into the buffer cache, but it
* will just try to release the buffer from the cache later
* on in ffs_read().
*
* ZFS does not pay attention to IO_DIRECT for reads.
*
* UFS does not pay attention to IO_SYNC for reads.
*
* ZFS pays attention to IO_SYNC (which translates into the
* Solaris define FRSYNC for zfs_read()) for reads. It
* attempts to sync the file before reading.
*
* So, to attempt to provide some barrier semantics in the
* BIO_ORDERED case, set both IO_DIRECT and IO_SYNC.
*/
error = VOP_READ(be_lun->vn, &xuio, (flags & BIO_ORDERED) ?
(IO_DIRECT|IO_SYNC) : 0, file_data->cred);
VOP_UNLOCK(be_lun->vn, 0);
} else {
struct mount *mountpoint;
int lock_flags;
(void)vn_start_write(be_lun->vn, &mountpoint, V_WAIT);
if (MNT_SHARED_WRITES(mountpoint)
|| ((mountpoint == NULL)
&& MNT_SHARED_WRITES(be_lun->vn->v_mount)))
lock_flags = LK_SHARED;
else
lock_flags = LK_EXCLUSIVE;
vn_lock(be_lun->vn, lock_flags | LK_RETRY);
binuptime(&beio->ds_t0);
devstat_start_transaction(beio->lun->disk_stats, &beio->ds_t0);
/*
* UFS pays attention to IO_DIRECT for writes. The write
* is done asynchronously. (Normally the write would just
* get put into cache.
*
* UFS pays attention to IO_SYNC for writes. It will
* attempt to write the buffer out synchronously if that
* flag is set.
*
* ZFS does not pay attention to IO_DIRECT for writes.
*
* ZFS pays attention to IO_SYNC (a.k.a. FSYNC or FRSYNC)
* for writes. It will flush the transaction from the
* cache before returning.
*
* So if we've got the BIO_ORDERED flag set, we want
* IO_SYNC in either the UFS or ZFS case.
*/
error = VOP_WRITE(be_lun->vn, &xuio, (flags & BIO_ORDERED) ?
IO_SYNC : 0, file_data->cred);
VOP_UNLOCK(be_lun->vn, 0);
vn_finished_write(mountpoint);
}
VFS_UNLOCK_GIANT(vfs_is_locked);
/*
* If we got an error, set the sense data to "MEDIUM ERROR" and
* return the I/O to the user.
*/
if (error != 0) {
char path_str[32];
ctl_scsi_path_string(io, path_str, sizeof(path_str));
/*
* XXX KDM ZFS returns ENOSPC when the underlying
* filesystem fills up. What kind of SCSI error should we
* return for that?
*/
printf("%s%s command returned errno %d\n", path_str,
(beio->bio_cmd == BIO_READ) ? "READ" : "WRITE", error);
ctl_set_medium_error(&io->scsiio);
ctl_complete_beio(beio);
return;
}
/*
* If this is a write, we're all done.
* If this is a read, we can now send the data to the user.
*/
if (beio->bio_cmd == BIO_WRITE) {
ctl_set_success(&io->scsiio);
SDT_PROBE(cbb, kernel, write, file_done, 0, 0, 0, 0, 0);
ctl_complete_beio(beio);
} else {
SDT_PROBE(cbb, kernel, read, file_done, 0, 0, 0, 0, 0);
io->scsiio.be_move_done = ctl_be_block_move_done;
io->scsiio.kern_data_ptr = (uint8_t *)beio->sg_segs;
io->scsiio.kern_data_len = beio->io_len;
io->scsiio.kern_total_len = beio->io_len;
io->scsiio.kern_rel_offset = 0;
io->scsiio.kern_data_resid = 0;
io->scsiio.kern_sg_entries = beio->num_segs;
io->io_hdr.flags |= CTL_FLAG_ALLOCATED | CTL_FLAG_KDPTR_SGLIST;
#ifdef CTL_TIME_IO
getbintime(&io->io_hdr.dma_start_bt);
#endif
ctl_datamove(io);
}
}
static void
ctl_be_block_flush_dev(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio)
{
struct bio *bio;
union ctl_io *io;
struct ctl_be_block_devdata *dev_data;
dev_data = &be_lun->backend.dev;
io = beio->io;
DPRINTF("entered\n");
/* This can't fail, it's a blocking allocation. */
bio = g_alloc_bio();
bio->bio_cmd = BIO_FLUSH;
bio->bio_flags |= BIO_ORDERED;
bio->bio_dev = dev_data->cdev;
bio->bio_offset = 0;
bio->bio_data = 0;
bio->bio_done = ctl_be_block_biodone;
bio->bio_caller1 = beio;
bio->bio_pblkno = 0;
/*
* We don't need to acquire the LUN lock here, because we are only
* sending one bio, and so there is no other context to synchronize
* with.
*/
beio->num_bios_sent = 1;
beio->send_complete = 1;
binuptime(&beio->ds_t0);
devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
(*dev_data->csw->d_strategy)(bio);
}
static void
ctl_be_block_dispatch_dev(struct ctl_be_block_lun *be_lun,
struct ctl_be_block_io *beio)
{
int i;
struct bio *bio;
struct ctl_be_block_devdata *dev_data;
off_t cur_offset;
int max_iosize;
DPRINTF("entered\n");
dev_data = &be_lun->backend.dev;
/*
* We have to limit our I/O size to the maximum supported by the
* backend device. Hopefully it is MAXPHYS. If the driver doesn't
* set it properly, use DFLTPHYS.
*/
max_iosize = dev_data->cdev->si_iosize_max;
if (max_iosize < PAGE_SIZE)
max_iosize = DFLTPHYS;
cur_offset = beio->io_offset;
/*
* XXX KDM need to accurately reflect the number of I/Os outstanding
* to a device.
*/
binuptime(&beio->ds_t0);
devstat_start_transaction(be_lun->disk_stats, &beio->ds_t0);
for (i = 0; i < beio->num_segs; i++) {
size_t cur_size;
uint8_t *cur_ptr;
cur_size = beio->sg_segs[i].len;
cur_ptr = beio->sg_segs[i].addr;
while (cur_size > 0) {
/* This can't fail, it's a blocking allocation. */
bio = g_alloc_bio();
KASSERT(bio != NULL, ("g_alloc_bio() failed!\n"));
bio->bio_cmd = beio->bio_cmd;
bio->bio_flags |= beio->bio_flags;
bio->bio_dev = dev_data->cdev;
bio->bio_caller1 = beio;
bio->bio_length = min(cur_size, max_iosize);
bio->bio_offset = cur_offset;
bio->bio_data = cur_ptr;
bio->bio_done = ctl_be_block_biodone;
bio->bio_pblkno = cur_offset / be_lun->blocksize;
cur_offset += bio->bio_length;
cur_ptr += bio->bio_length;
cur_size -= bio->bio_length;
/*
* Make sure we set the complete bit just before we
* issue the last bio so we don't wind up with a
* race.
*
* Use the LUN mutex here instead of a combination
* of atomic variables for simplicity.
*
* XXX KDM we could have a per-IO lock, but that
* would cause additional per-IO setup and teardown
* overhead. Hopefully there won't be too much
* contention on the LUN lock.
*/
mtx_lock(&be_lun->lock);
beio->num_bios_sent++;
if ((i == beio->num_segs - 1)
&& (cur_size == 0))
beio->send_complete = 1;
mtx_unlock(&be_lun->lock);
(*dev_data->csw->d_strategy)(bio);
}
}
}
static void
ctl_be_block_cw_dispatch(struct ctl_be_block_lun *be_lun,
union ctl_io *io)
{
struct ctl_be_block_io *beio;
struct ctl_be_block_softc *softc;
DPRINTF("entered\n");
softc = be_lun->softc;
beio = ctl_alloc_beio(softc);
if (beio == NULL) {
/*
* This should not happen. ctl_alloc_beio() will call
* ctl_grow_beio() with a blocking malloc as needed.
* A malloc with M_WAITOK should not fail.
*/
ctl_set_busy(&io->scsiio);
ctl_done(io);
return;
}
beio->io = io;
beio->softc = softc;
beio->lun = be_lun;
io->io_hdr.ctl_private[CTL_PRIV_BACKEND].ptr = beio;
switch (io->scsiio.cdb[0]) {
case SYNCHRONIZE_CACHE:
case SYNCHRONIZE_CACHE_16:
beio->ds_trans_type = DEVSTAT_NO_DATA;
beio->ds_tag_type = DEVSTAT_TAG_ORDERED;
beio->io_len = 0;
be_lun->lun_flush(be_lun, beio);
break;
default:
panic("Unhandled CDB type %#x", io->scsiio.cdb[0]);
break;
}
}
SDT_PROBE_DEFINE1(cbb, kernel, read, start, start, "uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, write, start, start, "uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, read, alloc_done, alloc_done, "uint64_t");
SDT_PROBE_DEFINE1(cbb, kernel, write, alloc_done, alloc_done, "uint64_t");
static void
ctl_be_block_dispatch(struct ctl_be_block_lun *be_lun,
union ctl_io *io)
{
struct ctl_be_block_io *beio;
struct ctl_be_block_softc *softc;
struct ctl_lba_len lbalen;
uint64_t len_left, io_size_bytes;
int i;
softc = be_lun->softc;
DPRINTF("entered\n");
if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_IN) {
SDT_PROBE(cbb, kernel, read, start, 0, 0, 0, 0, 0);
} else {
SDT_PROBE(cbb, kernel, write, start, 0, 0, 0, 0, 0);
}
memcpy(&lbalen, io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN].bytes,
sizeof(lbalen));
io_size_bytes = lbalen.len * be_lun->blocksize;
/*
* XXX KDM this is temporary, until we implement chaining of beio
* structures and multiple datamove calls to move all the data in
* or out.
*/
if (io_size_bytes > CTLBLK_MAX_IO_SIZE) {
printf("%s: IO length %ju > max io size %u\n", __func__,
io_size_bytes, CTLBLK_MAX_IO_SIZE);
ctl_set_invalid_field(&io->scsiio,
/*sks_valid*/ 0,
/*command*/ 1,
/*field*/ 0,
/*bit_valid*/ 0,
/*bit*/ 0);
ctl_done(io);
return;
}
beio = ctl_alloc_beio(softc);
if (beio == NULL) {
/*
* This should not happen. ctl_alloc_beio() will call
* ctl_grow_beio() with a blocking malloc as needed.
* A malloc with M_WAITOK should not fail.
*/
ctl_set_busy(&io->scsiio);
ctl_done(io);
return;
}
beio->io = io;
beio->softc = softc;
beio->lun = be_lun;
io->io_hdr.ctl_private[CTL_PRIV_BACKEND].ptr = beio;
/*
* If the I/O came down with an ordered or head of queue tag, set
* the BIO_ORDERED attribute. For head of queue tags, that's
* pretty much the best we can do.
*
* XXX KDM we don't have a great way to easily know about the FUA
* bit right now (it is decoded in ctl_read_write(), but we don't
* pass that knowledge to the backend), and in any case we would
* need to determine how to handle it.
*/
if ((io->scsiio.tag_type == CTL_TAG_ORDERED)
|| (io->scsiio.tag_type == CTL_TAG_HEAD_OF_QUEUE))
beio->bio_flags = BIO_ORDERED;
switch (io->scsiio.tag_type) {
case CTL_TAG_ORDERED:
beio->ds_tag_type = DEVSTAT_TAG_ORDERED;
break;
case CTL_TAG_HEAD_OF_QUEUE:
beio->ds_tag_type = DEVSTAT_TAG_HEAD;
break;
case CTL_TAG_UNTAGGED:
case CTL_TAG_SIMPLE:
case CTL_TAG_ACA:
default:
beio->ds_tag_type = DEVSTAT_TAG_SIMPLE;
break;
}
/*
* This path handles read and write only. The config write path
* handles flush operations.
*/
if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_IN) {
beio->bio_cmd = BIO_READ;
beio->ds_trans_type = DEVSTAT_READ;
} else {
beio->bio_cmd = BIO_WRITE;
beio->ds_trans_type = DEVSTAT_WRITE;
}
beio->io_len = lbalen.len * be_lun->blocksize;
beio->io_offset = lbalen.lba * be_lun->blocksize;
DPRINTF("%s at LBA %jx len %u\n",
(beio->bio_cmd == BIO_READ) ? "READ" : "WRITE",
(uintmax_t)lbalen.lba, lbalen.len);
for (i = 0, len_left = io_size_bytes; i < CTLBLK_MAX_SEGS &&
len_left > 0; i++) {
/*
* Setup the S/G entry for this chunk.
*/
beio->sg_segs[i].len = min(MAXPHYS, len_left);
beio->sg_segs[i].addr = uma_zalloc(be_lun->lun_zone, M_WAITOK);
/*
* uma_zalloc() can in theory return NULL even with M_WAITOK
* if it can't pull more memory into the zone.
*/
if (beio->sg_segs[i].addr == NULL) {
ctl_set_busy(&io->scsiio);
ctl_complete_beio(beio);
return;
}
DPRINTF("segment %d addr %p len %zd\n", i,
beio->sg_segs[i].addr, beio->sg_segs[i].len);
beio->num_segs++;
len_left -= beio->sg_segs[i].len;
}
/*
* For the read case, we need to read the data into our buffers and
* then we can send it back to the user. For the write case, we
* need to get the data from the user first.
*/
if (beio->bio_cmd == BIO_READ) {
SDT_PROBE(cbb, kernel, read, alloc_done, 0, 0, 0, 0, 0);
be_lun->dispatch(be_lun, beio);
} else {
SDT_PROBE(cbb, kernel, write, alloc_done, 0, 0, 0, 0, 0);
io->scsiio.be_move_done = ctl_be_block_move_done;
io->scsiio.kern_data_ptr = (uint8_t *)beio->sg_segs;
io->scsiio.kern_data_len = beio->io_len;
io->scsiio.kern_total_len = beio->io_len;
io->scsiio.kern_rel_offset = 0;
io->scsiio.kern_data_resid = 0;
io->scsiio.kern_sg_entries = beio->num_segs;
io->io_hdr.flags |= CTL_FLAG_ALLOCATED | CTL_FLAG_KDPTR_SGLIST;
#ifdef CTL_TIME_IO
getbintime(&io->io_hdr.dma_start_bt);
#endif
ctl_datamove(io);
}
}
static void
ctl_be_block_worker(void *context, int pending)
{
struct ctl_be_block_lun *be_lun;
struct ctl_be_block_softc *softc;
union ctl_io *io;
be_lun = (struct ctl_be_block_lun *)context;
softc = be_lun->softc;
DPRINTF("entered\n");
mtx_lock(&be_lun->lock);
for (;;) {
io = (union ctl_io *)STAILQ_FIRST(&be_lun->datamove_queue);
if (io != NULL) {
struct ctl_be_block_io *beio;
DPRINTF("datamove queue\n");
STAILQ_REMOVE(&be_lun->datamove_queue, &io->io_hdr,
ctl_io_hdr, links);
mtx_unlock(&be_lun->lock);
beio = (struct ctl_be_block_io *)
io->io_hdr.ctl_private[CTL_PRIV_BACKEND].ptr;
be_lun->dispatch(be_lun, beio);
mtx_lock(&be_lun->lock);
continue;
}
io = (union ctl_io *)STAILQ_FIRST(&be_lun->config_write_queue);
if (io != NULL) {
DPRINTF("config write queue\n");
STAILQ_REMOVE(&be_lun->config_write_queue, &io->io_hdr,
ctl_io_hdr, links);
mtx_unlock(&be_lun->lock);
ctl_be_block_cw_dispatch(be_lun, io);
mtx_lock(&be_lun->lock);
continue;
}
io = (union ctl_io *)STAILQ_FIRST(&be_lun->input_queue);
if (io != NULL) {
DPRINTF("input queue\n");
STAILQ_REMOVE(&be_lun->input_queue, &io->io_hdr,
ctl_io_hdr, links);
mtx_unlock(&be_lun->lock);
/*
* We must drop the lock, since this routine and
* its children may sleep.
*/
ctl_be_block_dispatch(be_lun, io);
mtx_lock(&be_lun->lock);
continue;
}
/*
* If we get here, there is no work left in the queues, so
* just break out and let the task queue go to sleep.
*/
break;
}
mtx_unlock(&be_lun->lock);
}
/*
* Entry point from CTL to the backend for I/O. We queue everything to a
* work thread, so this just puts the I/O on a queue and wakes up the
* thread.
*/
static int
ctl_be_block_submit(union ctl_io *io)
{
struct ctl_be_block_lun *be_lun;
struct ctl_be_lun *ctl_be_lun;
int retval;
DPRINTF("entered\n");
retval = CTL_RETVAL_COMPLETE;
ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
CTL_PRIV_BACKEND_LUN].ptr;
be_lun = (struct ctl_be_block_lun *)ctl_be_lun->be_lun;
/*
* Make sure we only get SCSI I/O.
*/
KASSERT(io->io_hdr.io_type == CTL_IO_SCSI, ("Non-SCSI I/O (type "
"%#x) encountered", io->io_hdr.io_type));
mtx_lock(&be_lun->lock);
/*
* XXX KDM make sure that links is okay to use at this point.
* Otherwise, we either need to add another field to ctl_io_hdr,
* or deal with resource allocation here.
*/
STAILQ_INSERT_TAIL(&be_lun->input_queue, &io->io_hdr, links);
mtx_unlock(&be_lun->lock);
taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
return (retval);
}
static int
ctl_be_block_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
int flag, struct thread *td)
{
struct ctl_be_block_softc *softc;
int error;
softc = &backend_block_softc;
error = 0;
switch (cmd) {
case CTL_LUN_REQ: {
struct ctl_lun_req *lun_req;
lun_req = (struct ctl_lun_req *)addr;
switch (lun_req->reqtype) {
case CTL_LUNREQ_CREATE:
error = ctl_be_block_create(softc, lun_req);
break;
case CTL_LUNREQ_RM:
error = ctl_be_block_rm(softc, lun_req);
break;
default:
lun_req->status = CTL_LUN_ERROR;
snprintf(lun_req->error_str, sizeof(lun_req->error_str),
"%s: invalid LUN request type %d", __func__,
lun_req->reqtype);
break;
}
break;
}
default:
error = ENOTTY;
break;
}
return (error);
}
static int
ctl_be_block_open_file(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
{
struct ctl_be_block_filedata *file_data;
struct ctl_lun_create_params *params;
struct vattr vattr;
int error;
error = 0;
file_data = &be_lun->backend.file;
params = &req->reqdata.create;
be_lun->dev_type = CTL_BE_BLOCK_FILE;
be_lun->dispatch = ctl_be_block_dispatch_file;
be_lun->lun_flush = ctl_be_block_flush_file;
error = VOP_GETATTR(be_lun->vn, &vattr, curthread->td_ucred);
if (error != 0) {
snprintf(req->error_str, sizeof(req->error_str),
"error calling VOP_GETATTR() for file %s",
be_lun->dev_path);
return (error);
}
/*
* Verify that we have the ability to upgrade to exclusive
* access on this file so we can trap errors at open instead
* of reporting them during first access.
*/
if (VOP_ISLOCKED(be_lun->vn) != LK_EXCLUSIVE) {
vn_lock(be_lun->vn, LK_UPGRADE | LK_RETRY);
if (be_lun->vn->v_iflag & VI_DOOMED) {
error = EBADF;
snprintf(req->error_str, sizeof(req->error_str),
"error locking file %s", be_lun->dev_path);
return (error);
}
}
file_data->cred = crhold(curthread->td_ucred);
be_lun->size_bytes = vattr.va_size;
/*
* We set the multi thread flag for file operations because all
* filesystems (in theory) are capable of allowing multiple readers
* of a file at once. So we want to get the maximum possible
* concurrency.
*/
be_lun->flags |= CTL_BE_BLOCK_LUN_MULTI_THREAD;
/*
* XXX KDM vattr.va_blocksize may be larger than 512 bytes here.
* With ZFS, it is 131072 bytes. Block sizes that large don't work
* with disklabel and UFS on FreeBSD at least. Large block sizes
* may not work with other OSes as well. So just export a sector
* size of 512 bytes, which should work with any OS or
* application. Since our backing is a file, any block size will
* work fine for the backing store.
*/
#if 0
be_lun->blocksize= vattr.va_blocksize;
#endif
if (params->blocksize_bytes != 0)
be_lun->blocksize = params->blocksize_bytes;
else
be_lun->blocksize = 512;
/*
* Sanity check. The media size has to be at least one
* sector long.
*/
if (be_lun->size_bytes < be_lun->blocksize) {
error = EINVAL;
snprintf(req->error_str, sizeof(req->error_str),
"file %s size %ju < block size %u", be_lun->dev_path,
(uintmax_t)be_lun->size_bytes, be_lun->blocksize);
}
return (error);
}
static int
ctl_be_block_open_dev(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
{
struct ctl_lun_create_params *params;
struct vattr vattr;
struct cdev *dev;
struct cdevsw *devsw;
int error;
params = &req->reqdata.create;
be_lun->dev_type = CTL_BE_BLOCK_DEV;
be_lun->dispatch = ctl_be_block_dispatch_dev;
be_lun->lun_flush = ctl_be_block_flush_dev;
be_lun->backend.dev.cdev = be_lun->vn->v_rdev;
be_lun->backend.dev.csw = dev_refthread(be_lun->backend.dev.cdev,
&be_lun->backend.dev.dev_ref);
if (be_lun->backend.dev.csw == NULL)
panic("Unable to retrieve device switch");
error = VOP_GETATTR(be_lun->vn, &vattr, NOCRED);
if (error) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error getting vnode attributes for device %s",
__func__, be_lun->dev_path);
return (error);
}
dev = be_lun->vn->v_rdev;
devsw = dev->si_devsw;
if (!devsw->d_ioctl) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: no d_ioctl for device %s!", __func__,
be_lun->dev_path);
return (ENODEV);
}
error = devsw->d_ioctl(dev, DIOCGSECTORSIZE,
(caddr_t)&be_lun->blocksize, FREAD,
curthread);
if (error) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error %d returned for DIOCGSECTORSIZE ioctl "
"on %s!", __func__, error, be_lun->dev_path);
return (error);
}
/*
* If the user has asked for a blocksize that is greater than the
* backing device's blocksize, we can do it only if the blocksize
* the user is asking for is an even multiple of the underlying
* device's blocksize.
*/
if ((params->blocksize_bytes != 0)
&& (params->blocksize_bytes > be_lun->blocksize)) {
uint32_t bs_multiple, tmp_blocksize;
bs_multiple = params->blocksize_bytes / be_lun->blocksize;
tmp_blocksize = bs_multiple * be_lun->blocksize;
if (tmp_blocksize == params->blocksize_bytes) {
be_lun->blocksize = params->blocksize_bytes;
} else {
snprintf(req->error_str, sizeof(req->error_str),
"%s: requested blocksize %u is not an even "
"multiple of backing device blocksize %u",
__func__, params->blocksize_bytes,
be_lun->blocksize);
return (EINVAL);
}
} else if ((params->blocksize_bytes != 0)
&& (params->blocksize_bytes != be_lun->blocksize)) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: requested blocksize %u < backing device "
"blocksize %u", __func__, params->blocksize_bytes,
be_lun->blocksize);
return (EINVAL);
}
error = devsw->d_ioctl(dev, DIOCGMEDIASIZE,
(caddr_t)&be_lun->size_bytes, FREAD,
curthread);
if (error) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error %d returned for DIOCGMEDIASIZE ioctl "
"on %s!", __func__, error, be_lun->dev_path);
return (error);
}
return (0);
}
static int
ctl_be_block_close(struct ctl_be_block_lun *be_lun)
{
DROP_GIANT();
if (be_lun->vn) {
int flags = FREAD | FWRITE;
int vfs_is_locked = 0;
switch (be_lun->dev_type) {
case CTL_BE_BLOCK_DEV:
if (be_lun->backend.dev.csw) {
dev_relthread(be_lun->backend.dev.cdev,
be_lun->backend.dev.dev_ref);
be_lun->backend.dev.csw = NULL;
be_lun->backend.dev.cdev = NULL;
}
break;
case CTL_BE_BLOCK_FILE:
vfs_is_locked = VFS_LOCK_GIANT(be_lun->vn->v_mount);
break;
case CTL_BE_BLOCK_NONE:
default:
panic("Unexpected backend type.");
break;
}
(void)vn_close(be_lun->vn, flags, NOCRED, curthread);
be_lun->vn = NULL;
switch (be_lun->dev_type) {
case CTL_BE_BLOCK_DEV:
break;
case CTL_BE_BLOCK_FILE:
VFS_UNLOCK_GIANT(vfs_is_locked);
if (be_lun->backend.file.cred != NULL) {
crfree(be_lun->backend.file.cred);
be_lun->backend.file.cred = NULL;
}
break;
case CTL_BE_BLOCK_NONE:
default:
panic("Unexpected backend type.");
break;
}
}
PICKUP_GIANT();
return (0);
}
static int
ctl_be_block_open(struct ctl_be_block_softc *softc,
struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req)
{
struct nameidata nd;
int flags;
int error;
int vfs_is_locked;
/*
* XXX KDM allow a read-only option?
*/
flags = FREAD | FWRITE;
error = 0;
if (rootvnode == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: Root filesystem is not mounted", __func__);
return (1);
}
if (!curthread->td_proc->p_fd->fd_cdir) {
curthread->td_proc->p_fd->fd_cdir = rootvnode;
VREF(rootvnode);
}
if (!curthread->td_proc->p_fd->fd_rdir) {
curthread->td_proc->p_fd->fd_rdir = rootvnode;
VREF(rootvnode);
}
if (!curthread->td_proc->p_fd->fd_jdir) {
curthread->td_proc->p_fd->fd_jdir = rootvnode;
VREF(rootvnode);
}
again:
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, be_lun->dev_path, curthread);
error = vn_open(&nd, &flags, 0, NULL);
if (error) {
/*
* This is the only reasonable guess we can make as far as
* path if the user doesn't give us a fully qualified path.
* If they want to specify a file, they need to specify the
* full path.
*/
if (be_lun->dev_path[0] != '/') {
char *dev_path = "/dev/";
char *dev_name;
/* Try adding device path at beginning of name */
dev_name = malloc(strlen(be_lun->dev_path)
+ strlen(dev_path) + 1,
M_CTLBLK, M_WAITOK);
if (dev_name) {
sprintf(dev_name, "%s%s", dev_path,
be_lun->dev_path);
free(be_lun->dev_path, M_CTLBLK);
be_lun->dev_path = dev_name;
goto again;
}
}
snprintf(req->error_str, sizeof(req->error_str),
"%s: error opening %s", __func__, be_lun->dev_path);
return (error);
}
vfs_is_locked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
be_lun->vn = nd.ni_vp;
/* We only support disks and files. */
if (vn_isdisk(be_lun->vn, &error)) {
error = ctl_be_block_open_dev(be_lun, req);
} else if (be_lun->vn->v_type == VREG) {
error = ctl_be_block_open_file(be_lun, req);
} else {
error = EINVAL;
snprintf(req->error_str, sizeof(req->error_str),
"%s is not a disk or file", be_lun->dev_path);
}
VOP_UNLOCK(be_lun->vn, 0);
VFS_UNLOCK_GIANT(vfs_is_locked);
if (error != 0) {
ctl_be_block_close(be_lun);
return (error);
}
be_lun->blocksize_shift = fls(be_lun->blocksize) - 1;
be_lun->size_blocks = be_lun->size_bytes >> be_lun->blocksize_shift;
return (0);
}
static int
ctl_be_block_mem_ctor(void *mem, int size, void *arg, int flags)
{
return (0);
}
static void
ctl_be_block_mem_dtor(void *mem, int size, void *arg)
{
bzero(mem, size);
}
static int
ctl_be_block_create(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
{
struct ctl_be_block_lun *be_lun;
struct ctl_lun_create_params *params;
struct ctl_be_arg *file_arg;
char tmpstr[32];
int retval, num_threads;
int i;
params = &req->reqdata.create;
retval = 0;
num_threads = cbb_num_threads;
file_arg = NULL;
be_lun = malloc(sizeof(*be_lun), M_CTLBLK, M_ZERO | M_WAITOK);
if (be_lun == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error allocating %zd bytes", __func__,
sizeof(*be_lun));
goto bailout_error;
}
be_lun->softc = softc;
STAILQ_INIT(&be_lun->input_queue);
STAILQ_INIT(&be_lun->config_write_queue);
STAILQ_INIT(&be_lun->datamove_queue);
sprintf(be_lun->lunname, "cblk%d", softc->num_luns);
mtx_init(&be_lun->lock, be_lun->lunname, NULL, MTX_DEF);
be_lun->lun_zone = uma_zcreate(be_lun->lunname, MAXPHYS,
ctl_be_block_mem_ctor, ctl_be_block_mem_dtor, NULL, NULL,
/*align*/ 0, /*flags*/0);
if (be_lun->lun_zone == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error allocating UMA zone", __func__);
goto bailout_error;
}
if (params->flags & CTL_LUN_FLAG_DEV_TYPE)
be_lun->ctl_be_lun.lun_type = params->device_type;
else
be_lun->ctl_be_lun.lun_type = T_DIRECT;
if (be_lun->ctl_be_lun.lun_type == T_DIRECT) {
for (i = 0; i < req->num_be_args; i++) {
if (strcmp(req->kern_be_args[i].name, "file") == 0) {
file_arg = &req->kern_be_args[i];
break;
}
}
if (file_arg == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: no file argument specified", __func__);
goto bailout_error;
}
be_lun->dev_path = malloc(file_arg->vallen, M_CTLBLK,
M_WAITOK | M_ZERO);
if (be_lun->dev_path == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error allocating %d bytes", __func__,
file_arg->vallen);
goto bailout_error;
}
strlcpy(be_lun->dev_path, (char *)file_arg->value,
file_arg->vallen);
retval = ctl_be_block_open(softc, be_lun, req);
if (retval != 0) {
retval = 0;
goto bailout_error;
}
/*
* Tell the user the size of the file/device.
*/
params->lun_size_bytes = be_lun->size_bytes;
/*
* The maximum LBA is the size - 1.
*/
be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
} else {
/*
* For processor devices, we don't have any size.
*/
be_lun->blocksize = 0;
be_lun->size_blocks = 0;
be_lun->size_bytes = 0;
be_lun->ctl_be_lun.maxlba = 0;
params->lun_size_bytes = 0;
/*
* Default to just 1 thread for processor devices.
*/
num_threads = 1;
}
/*
* XXX This searching loop might be refactored to be combined with
* the loop above,
*/
for (i = 0; i < req->num_be_args; i++) {
if (strcmp(req->kern_be_args[i].name, "num_threads") == 0) {
struct ctl_be_arg *thread_arg;
char num_thread_str[16];
int tmp_num_threads;
thread_arg = &req->kern_be_args[i];
strlcpy(num_thread_str, (char *)thread_arg->value,
min(thread_arg->vallen,
sizeof(num_thread_str)));
tmp_num_threads = strtol(num_thread_str, NULL, 0);
/*
* We don't let the user specify less than one
* thread, but hope he's clueful enough not to
* specify 1000 threads.
*/
if (tmp_num_threads < 1) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: invalid number of threads %s",
__func__, num_thread_str);
goto bailout_error;
}
num_threads = tmp_num_threads;
}
}
be_lun->flags = CTL_BE_BLOCK_LUN_UNCONFIGURED;
be_lun->ctl_be_lun.flags = CTL_LUN_FLAG_PRIMARY;
be_lun->ctl_be_lun.be_lun = be_lun;
be_lun->ctl_be_lun.blocksize = be_lun->blocksize;
/* Tell the user the blocksize we ended up using */
params->blocksize_bytes = be_lun->blocksize;
if (params->flags & CTL_LUN_FLAG_ID_REQ) {
be_lun->ctl_be_lun.req_lun_id = params->req_lun_id;
be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_ID_REQ;
} else
be_lun->ctl_be_lun.req_lun_id = 0;
be_lun->ctl_be_lun.lun_shutdown = ctl_be_block_lun_shutdown;
be_lun->ctl_be_lun.lun_config_status =
ctl_be_block_lun_config_status;
be_lun->ctl_be_lun.be = &ctl_be_block_driver;
if ((params->flags & CTL_LUN_FLAG_SERIAL_NUM) == 0) {
snprintf(tmpstr, sizeof(tmpstr), "MYSERIAL%4d",
softc->num_luns);
strncpy((char *)be_lun->ctl_be_lun.serial_num, tmpstr,
ctl_min(sizeof(be_lun->ctl_be_lun.serial_num),
sizeof(tmpstr)));
/* Tell the user what we used for a serial number */
strncpy((char *)params->serial_num, tmpstr,
ctl_min(sizeof(params->serial_num), sizeof(tmpstr)));
} else {
strncpy((char *)be_lun->ctl_be_lun.serial_num,
params->serial_num,
ctl_min(sizeof(be_lun->ctl_be_lun.serial_num),
sizeof(params->serial_num)));
}
if ((params->flags & CTL_LUN_FLAG_DEVID) == 0) {
snprintf(tmpstr, sizeof(tmpstr), "MYDEVID%4d", softc->num_luns);
strncpy((char *)be_lun->ctl_be_lun.device_id, tmpstr,
ctl_min(sizeof(be_lun->ctl_be_lun.device_id),
sizeof(tmpstr)));
/* Tell the user what we used for a device ID */
strncpy((char *)params->device_id, tmpstr,
ctl_min(sizeof(params->device_id), sizeof(tmpstr)));
} else {
strncpy((char *)be_lun->ctl_be_lun.device_id,
params->device_id,
ctl_min(sizeof(be_lun->ctl_be_lun.device_id),
sizeof(params->device_id)));
}
TASK_INIT(&be_lun->io_task, /*priority*/0, ctl_be_block_worker, be_lun);
be_lun->io_taskqueue = taskqueue_create(be_lun->lunname, M_WAITOK,
taskqueue_thread_enqueue, /*context*/&be_lun->io_taskqueue);
if (be_lun->io_taskqueue == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: Unable to create taskqueue", __func__);
goto bailout_error;
}
/*
* Note that we start the same number of threads by default for
* both the file case and the block device case. For the file
* case, we need multiple threads to allow concurrency, because the
* vnode interface is designed to be a blocking interface. For the
* block device case, ZFS zvols at least will block the caller's
* context in many instances, and so we need multiple threads to
* overcome that problem. Other block devices don't need as many
* threads, but they shouldn't cause too many problems.
*
* If the user wants to just have a single thread for a block
* device, he can specify that when the LUN is created, or change
* the tunable/sysctl to alter the default number of threads.
*/
retval = taskqueue_start_threads(&be_lun->io_taskqueue,
/*num threads*/num_threads,
/*priority*/PWAIT,
/*thread name*/
"%s taskq", be_lun->lunname);
if (retval != 0)
goto bailout_error;
be_lun->num_threads = num_threads;
mtx_lock(&softc->lock);
softc->num_luns++;
STAILQ_INSERT_TAIL(&softc->lun_list, be_lun, links);
mtx_unlock(&softc->lock);
retval = ctl_add_lun(&be_lun->ctl_be_lun);
if (retval != 0) {
mtx_lock(&softc->lock);
STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_block_lun,
links);
softc->num_luns--;
mtx_unlock(&softc->lock);
snprintf(req->error_str, sizeof(req->error_str),
"%s: ctl_add_lun() returned error %d, see dmesg for "
"details", __func__, retval);
retval = 0;
goto bailout_error;
}
mtx_lock(&softc->lock);
/*
* Tell the config_status routine that we're waiting so it won't
* clean up the LUN in the event of an error.
*/
be_lun->flags |= CTL_BE_BLOCK_LUN_WAITING;
while (be_lun->flags & CTL_BE_BLOCK_LUN_UNCONFIGURED) {
retval = msleep(be_lun, &softc->lock, PCATCH, "ctlblk", 0);
if (retval == EINTR)
break;
}
be_lun->flags &= ~CTL_BE_BLOCK_LUN_WAITING;
if (be_lun->flags & CTL_BE_BLOCK_LUN_CONFIG_ERR) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: LUN configuration error, see dmesg for details",
__func__);
STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_block_lun,
links);
softc->num_luns--;
mtx_unlock(&softc->lock);
goto bailout_error;
} else {
params->req_lun_id = be_lun->ctl_be_lun.lun_id;
}
mtx_unlock(&softc->lock);
be_lun->disk_stats = devstat_new_entry("cbb", params->req_lun_id,
be_lun->blocksize,
DEVSTAT_ALL_SUPPORTED,
be_lun->ctl_be_lun.lun_type
| DEVSTAT_TYPE_IF_OTHER,
DEVSTAT_PRIORITY_OTHER);
req->status = CTL_LUN_OK;
return (retval);
bailout_error:
req->status = CTL_LUN_ERROR;
ctl_be_block_close(be_lun);
free(be_lun->dev_path, M_CTLBLK);
free(be_lun, M_CTLBLK);
return (retval);
}
static int
ctl_be_block_rm(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
{
struct ctl_lun_rm_params *params;
struct ctl_be_block_lun *be_lun;
int retval;
params = &req->reqdata.rm;
mtx_lock(&softc->lock);
be_lun = NULL;
STAILQ_FOREACH(be_lun, &softc->lun_list, links) {
if (be_lun->ctl_be_lun.lun_id == params->lun_id)
break;
}
mtx_unlock(&softc->lock);
if (be_lun == NULL) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: LUN %u is not managed by the block backend",
__func__, params->lun_id);
goto bailout_error;
}
retval = ctl_disable_lun(&be_lun->ctl_be_lun);
if (retval != 0) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error %d returned from ctl_disable_lun() for "
"LUN %d", __func__, retval, params->lun_id);
goto bailout_error;
}
retval = ctl_invalidate_lun(&be_lun->ctl_be_lun);
if (retval != 0) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: error %d returned from ctl_invalidate_lun() for "
"LUN %d", __func__, retval, params->lun_id);
goto bailout_error;
}
mtx_lock(&softc->lock);
be_lun->flags |= CTL_BE_BLOCK_LUN_WAITING;
while ((be_lun->flags & CTL_BE_BLOCK_LUN_UNCONFIGURED) == 0) {
retval = msleep(be_lun, &softc->lock, PCATCH, "ctlblk", 0);
if (retval == EINTR)
break;
}
be_lun->flags &= ~CTL_BE_BLOCK_LUN_WAITING;
if ((be_lun->flags & CTL_BE_BLOCK_LUN_UNCONFIGURED) == 0) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: interrupted waiting for LUN to be freed",
__func__);
mtx_unlock(&softc->lock);
goto bailout_error;
}
STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_block_lun, links);
softc->num_luns--;
mtx_unlock(&softc->lock);
taskqueue_drain(be_lun->io_taskqueue, &be_lun->io_task);
taskqueue_free(be_lun->io_taskqueue);
ctl_be_block_close(be_lun);
if (be_lun->disk_stats != NULL)
devstat_remove_entry(be_lun->disk_stats);
uma_zdestroy(be_lun->lun_zone);
free(be_lun->dev_path, M_CTLBLK);
free(be_lun, M_CTLBLK);
req->status = CTL_LUN_OK;
return (0);
bailout_error:
req->status = CTL_LUN_ERROR;
return (0);
}
static void
ctl_be_block_lun_shutdown(void *be_lun)
{
struct ctl_be_block_lun *lun;
struct ctl_be_block_softc *softc;
lun = (struct ctl_be_block_lun *)be_lun;
softc = lun->softc;
mtx_lock(&softc->lock);
lun->flags |= CTL_BE_BLOCK_LUN_UNCONFIGURED;
if (lun->flags & CTL_BE_BLOCK_LUN_WAITING)
wakeup(lun);
mtx_unlock(&softc->lock);
}
static void
ctl_be_block_lun_config_status(void *be_lun, ctl_lun_config_status status)
{
struct ctl_be_block_lun *lun;
struct ctl_be_block_softc *softc;
lun = (struct ctl_be_block_lun *)be_lun;
softc = lun->softc;
if (status == CTL_LUN_CONFIG_OK) {
mtx_lock(&softc->lock);
lun->flags &= ~CTL_BE_BLOCK_LUN_UNCONFIGURED;
if (lun->flags & CTL_BE_BLOCK_LUN_WAITING)
wakeup(lun);
mtx_unlock(&softc->lock);
/*
* We successfully added the LUN, attempt to enable it.
*/
if (ctl_enable_lun(&lun->ctl_be_lun) != 0) {
printf("%s: ctl_enable_lun() failed!\n", __func__);
if (ctl_invalidate_lun(&lun->ctl_be_lun) != 0) {
printf("%s: ctl_invalidate_lun() failed!\n",
__func__);
}
}
return;
}
mtx_lock(&softc->lock);
lun->flags &= ~CTL_BE_BLOCK_LUN_UNCONFIGURED;
lun->flags |= CTL_BE_BLOCK_LUN_CONFIG_ERR;
wakeup(lun);
mtx_unlock(&softc->lock);
}
static int
ctl_be_block_config_write(union ctl_io *io)
{
struct ctl_be_block_lun *be_lun;
struct ctl_be_lun *ctl_be_lun;
int retval;
retval = 0;
DPRINTF("entered\n");
ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
CTL_PRIV_BACKEND_LUN].ptr;
be_lun = (struct ctl_be_block_lun *)ctl_be_lun->be_lun;
switch (io->scsiio.cdb[0]) {
case SYNCHRONIZE_CACHE:
case SYNCHRONIZE_CACHE_16:
/*
* The upper level CTL code will filter out any CDBs with
* the immediate bit set and return the proper error.
*
* We don't really need to worry about what LBA range the
* user asked to be synced out. When they issue a sync
* cache command, we'll sync out the whole thing.
*/
mtx_lock(&be_lun->lock);
STAILQ_INSERT_TAIL(&be_lun->config_write_queue, &io->io_hdr,
links);
mtx_unlock(&be_lun->lock);
taskqueue_enqueue(be_lun->io_taskqueue, &be_lun->io_task);
break;
case START_STOP_UNIT: {
struct scsi_start_stop_unit *cdb;
cdb = (struct scsi_start_stop_unit *)io->scsiio.cdb;
if (cdb->how & SSS_START)
retval = ctl_start_lun(ctl_be_lun);
else {
retval = ctl_stop_lun(ctl_be_lun);
/*
* XXX KDM Copan-specific offline behavior.
* Figure out a reasonable way to port this?
*/
#ifdef NEEDTOPORT
if ((retval == 0)
&& (cdb->byte2 & SSS_ONOFFLINE))
retval = ctl_lun_offline(ctl_be_lun);
#endif
}
/*
* In general, the above routines should not fail. They
* just set state for the LUN. So we've got something
* pretty wrong here if we can't start or stop the LUN.
*/
if (retval != 0) {
ctl_set_internal_failure(&io->scsiio,
/*sks_valid*/ 1,
/*retry_count*/ 0xf051);
retval = CTL_RETVAL_COMPLETE;
} else {
ctl_set_success(&io->scsiio);
}
ctl_config_write_done(io);
break;
}
default:
ctl_set_invalid_opcode(&io->scsiio);
ctl_config_write_done(io);
retval = CTL_RETVAL_COMPLETE;
break;
}
return (retval);
}
static int
ctl_be_block_config_read(union ctl_io *io)
{
return (0);
}
static int
ctl_be_block_lun_info(void *be_lun, struct sbuf *sb)
{
struct ctl_be_block_lun *lun;
int retval;
lun = (struct ctl_be_block_lun *)be_lun;
retval = 0;
retval = sbuf_printf(sb, "<num_threads>");
if (retval != 0)
goto bailout;
retval = sbuf_printf(sb, "%d", lun->num_threads);
if (retval != 0)
goto bailout;
retval = sbuf_printf(sb, "</num_threads>");
/*
* For processor devices, we don't have a path variable.
*/
if ((retval != 0)
|| (lun->dev_path == NULL))
goto bailout;
retval = sbuf_printf(sb, "<file>");
if (retval != 0)
goto bailout;
retval = ctl_sbuf_printf_esc(sb, lun->dev_path);
if (retval != 0)
goto bailout;
retval = sbuf_printf(sb, "</file>\n");
bailout:
return (retval);
}
int
ctl_be_block_init(void)
{
struct ctl_be_block_softc *softc;
int retval;
softc = &backend_block_softc;
retval = 0;
mtx_init(&softc->lock, "ctlblk", NULL, MTX_DEF);
STAILQ_INIT(&softc->beio_free_queue);
STAILQ_INIT(&softc->disk_list);
STAILQ_INIT(&softc->lun_list);
ctl_grow_beio(softc, 200);
return (retval);
}
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