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freebsd-nq/sys/cam/ctl/ctl_backend_block.c
Edward Tomasz Napierala d2a0972d46 Make SYNCHRONIZE CACHE work with LUNs backed by device files (as opposed 
to regular files, which already worked fine).  With this change, it's no
longer neccessary to use "ctladm realsync off" workaround.
2013-04-06 10:34:02 +00:00

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/*-
* Copyright (c) 2003 Silicon Graphics International Corp.
* Copyright (c) 2009-2011 Spectra Logic Corporation
* Copyright (c) 2012 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by Edward Tomasz Napierala
* under sponsorship from the FreeBSD Foundation.
*
* 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 int ctl_be_block_modify_file(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req);
static int ctl_be_block_modify_dev(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req);
static int ctl_be_block_modify(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);
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 error, lock_flags;
DPRINTF("entered\n");
io = beio->io;
(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);
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 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;
}
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);
}
/*
* 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->bio_cmd = BIO_FLUSH;
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);
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;
case CTL_LUNREQ_MODIFY:
error = ctl_be_block_modify(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);
if (params->lun_size_bytes != 0)
be_lun->size_bytes = params->lun_size_bytes;
else
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);
}
if (params->lun_size_bytes != 0) {
if (params->lun_size_bytes > be_lun->size_bytes) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: requested LUN size %ju > backing device "
"size %ju", __func__,
(uintmax_t)params->lun_size_bytes,
(uintmax_t)be_lun->size_bytes);
return (EINVAL);
}
be_lun->size_bytes = params->lun_size_bytes;
}
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;
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:
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:
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;
/*
* 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);
}
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);
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);
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].kname, "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);
strlcpy(be_lun->dev_path, (char *)file_arg->kvalue,
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].kname, "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->kvalue,
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 int
ctl_be_block_modify_file(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req)
{
struct vattr vattr;
int error;
struct ctl_lun_modify_params *params;
params = &req->reqdata.modify;
if (params->lun_size_bytes != 0) {
be_lun->size_bytes = params->lun_size_bytes;
} else {
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);
}
be_lun->size_bytes = vattr.va_size;
}
return (0);
}
static int
ctl_be_block_modify_dev(struct ctl_be_block_lun *be_lun,
struct ctl_lun_req *req)
{
struct cdev *dev;
struct cdevsw *devsw;
int error;
struct ctl_lun_modify_params *params;
uint64_t size_bytes;
params = &req->reqdata.modify;
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, DIOCGMEDIASIZE,
(caddr_t)&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);
}
if (params->lun_size_bytes != 0) {
if (params->lun_size_bytes > size_bytes) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: requested LUN size %ju > backing device "
"size %ju", __func__,
(uintmax_t)params->lun_size_bytes,
(uintmax_t)size_bytes);
return (EINVAL);
}
be_lun->size_bytes = params->lun_size_bytes;
} else {
be_lun->size_bytes = size_bytes;
}
return (0);
}
static int
ctl_be_block_modify(struct ctl_be_block_softc *softc, struct ctl_lun_req *req)
{
struct ctl_lun_modify_params *params;
struct ctl_be_block_lun *be_lun;
int error;
params = &req->reqdata.modify;
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;
}
if (params->lun_size_bytes != 0) {
if (params->lun_size_bytes < be_lun->blocksize) {
snprintf(req->error_str, sizeof(req->error_str),
"%s: LUN size %ju < blocksize %u", __func__,
params->lun_size_bytes, be_lun->blocksize);
goto bailout_error;
}
}
vn_lock(be_lun->vn, LK_SHARED | LK_RETRY);
if (be_lun->vn->v_type == VREG)
error = ctl_be_block_modify_file(be_lun, req);
else
error = ctl_be_block_modify_dev(be_lun, req);
VOP_UNLOCK(be_lun->vn, 0);
if (error != 0)
goto bailout_error;
be_lun->size_blocks = be_lun->size_bytes >> be_lun->blocksize_shift;
/*
* The maximum LBA is the size - 1.
*
* XXX: Note that this field is being updated without locking,
* which might cause problems on 32-bit architectures.
*/
be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
ctl_lun_capacity_changed(&be_lun->ctl_be_lun);
/* Tell the user the exact size we ended up using */
params->lun_size_bytes = be_lun->size_bytes;
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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