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Re: [Qemu-devel] [PATCH 2/2] vus: Introduce a vhost-user-scsi sample app
|
From: |
Felipe Franciosi |
|
Subject: |
Re: [Qemu-devel] [PATCH 2/2] vus: Introduce a vhost-user-scsi sample application |
|
Date: |
Thu, 27 Oct 2016 12:48:24 +0000 |
Hello,
> On 27 Oct 2016, at 13:16, Paolo Bonzini <address@hidden> wrote:
>
>
>
> On 26/10/2016 17:26, Felipe Franciosi wrote:
>> This commit introduces a vhost-user-scsi backend sample application. It
>> must be linked with libiscsi and libvhost-user.
>>
>> To use it, compile with:
>> make tests/vhost-user-scsi
>>
>> And run as follows:
>> tests/vhost-user-scsi -u /tmp/vus.sock -i iscsi://uri_to_target/
>>
>> The application is currently limited at one LUN only and it processes
>> requests synchronously (therefore only achieving QD1). The purpose of
>> the code is to show how a backend can be implemented and to test the
>> vhost-user-scsi Qemu implementation.
>>
>> If a different instance of this vhost-user-scsi application is executed
>> at a remote host, a VM can be live migrated to such a host.
>
> Hi,
>
> the right directory for this is contrib/.
Cool. I was following suit from vhost-user-bridge which lives in tests/ today.
To me, it makes more sense for these to be in contrib/. I'll place my sample
application there for v2 and perhaps we should move vhost-user-bridge later?
>
> Is it possible to use GSource and GIOChannel instead for the event loop?
> There is some dead code (for example cb2 as far as I can see) and
> having the millionth implementation of an event loop distracts from the
> meat of the code. :)
That's true. I'll have a stab at using glib's event loop. The cb2 was meant to
be used for libiscsi's async submission, but I ended up with QD1 for
simplicity. You're right, it looks pretty dead at the minute. :)
Cheers,
Felipe
>
> Thanks,
>
> Paolo
>
>> Signed-off-by: Felipe Franciosi <address@hidden>
>> ---
>> tests/Makefile.include | 2 +
>> tests/vhost-user-scsi.c | 862
>> ++++++++++++++++++++++++++++++++++++++++++++++++
>> 2 files changed, 864 insertions(+)
>> create mode 100644 tests/vhost-user-scsi.c
>>
>> diff --git a/tests/Makefile.include b/tests/Makefile.include
>> index 7e6fd23..e61fe54 100644
>> --- a/tests/Makefile.include
>> +++ b/tests/Makefile.include
>> @@ -685,6 +685,8 @@ tests/test-filter-redirector$(EXESUF):
>> tests/test-filter-redirector.o $(qtest-ob
>> tests/test-x86-cpuid-compat$(EXESUF): tests/test-x86-cpuid-compat.o
>> $(qtest-obj-y)
>> tests/ivshmem-test$(EXESUF): tests/ivshmem-test.o
>> contrib/ivshmem-server/ivshmem-server.o $(libqos-pc-obj-y)
>> tests/vhost-user-bridge$(EXESUF): tests/vhost-user-bridge.o
>> contrib/libvhost-user/libvhost-user.o $(test-util-obj-y)
>> +tests/vhost-user-scsi.o-cflags := $(LIBISCSI_CFLAGS)
>> +tests/vhost-user-scsi$(EXESUF): tests/vhost-user-scsi.o
>> contrib/libvhost-user/libvhost-user.o $(test-util-obj-y) $(test-block-obj-y)
>> tests/test-uuid$(EXESUF): tests/test-uuid.o $(test-util-obj-y)
>> tests/test-arm-mptimer$(EXESUF): tests/test-arm-mptimer.o
>>
>> diff --git a/tests/vhost-user-scsi.c b/tests/vhost-user-scsi.c
>> new file mode 100644
>> index 0000000..c92b3b2
>> --- /dev/null
>> +++ b/tests/vhost-user-scsi.c
>> @@ -0,0 +1,862 @@
>> +/*
>> + * vhost-user-scsi sample application
>> + *
>> + * Copyright (c) 2016 Nutanix Inc. All rights reserved.
>> + *
>> + * Author:
>> + * Felipe Franciosi <address@hidden>
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 only.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "contrib/libvhost-user/libvhost-user.h"
>> +#include "hw/virtio/virtio-scsi.h"
>> +#include "iscsi/iscsi.h"
>> +
>> +#include <poll.h>
>> +
>> +#define VHOST_USER_SCSI_DEBUG 1
>> +
>> +/** Log helpers **/
>> +
>> +#define PPRE \
>> + struct timespec ts; \
>> + char timebuf[64]; \
>> + struct tm tm; \
>> + (void)clock_gettime(CLOCK_REALTIME, &ts); \
>> + (void)strftime(timebuf, 64, "%Y%m%d %T", gmtime_r(&ts.tv_sec, &tm))
>> +
>> +#define PEXT(lvl, msg, ...) do { \
>> + PPRE; \
>> + fprintf(stderr, "%s.%06ld " lvl ": %s:%s():%d: " msg "\n", \
>> + timebuf, ts.tv_nsec/1000, \
>> + __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
>> +} while(0)
>> +
>> +#define PNOR(lvl, msg, ...) do { \
>> + PPRE; \
>> + fprintf(stderr, "%s.%06ld " lvl ": " msg "\n", \
>> + timebuf, ts.tv_nsec/1000, ## __VA_ARGS__); \
>> +} while(0);
>> +
>> +#ifdef VHOST_USER_SCSI_DEBUG
>> +#define PDBG(msg, ...) PEXT("DBG", msg, ## __VA_ARGS__)
>> +#define PERR(msg, ...) PEXT("ERR", msg, ## __VA_ARGS__)
>> +#define PLOG(msg, ...) PEXT("LOG", msg, ## __VA_ARGS__)
>> +#else
>> +#define PDBG(msg, ...) { }
>> +#define PERR(msg, ...) PNOR("ERR", msg, ## __VA_ARGS__)
>> +#define PLOG(msg, ...) PNOR("LOG", msg, ## __VA_ARGS__)
>> +#endif
>> +
>> +/** vhost-user-scsi specific definitions **/
>> +
>> +/* TODO: MAX is defined at 8, should be 1024 */
>> +#define VUS_SCHED_MAX_FDS (1 + (2*VHOST_MAX_NR_VIRTQUEUE))
>> +
>> +#define VDEV_SCSI_MAX_LUNS 1 // Only 1 lun supported today
>> +#define VDEV_SCSI_MAX_DEVS 1 // Only 1 devices supported today
>> +
>> +#define ISCSI_INITIATOR "iqn.2016-10.com.nutanix:vhost-user-scsi"
>> +
>> +typedef void (*misc_cb) (short evt, void *pvt);
>> +
>> +typedef struct sched_data {
>> + vu_watch_cb cb1;
>> + misc_cb cb2;
>> + void *pvt;
>> + short evt;
>> +} sched_data_t;
>> +
>> +typedef struct sched {
>> + VuDev *vu_dev;
>> + nfds_t nfds;
>> + struct pollfd fds[VUS_SCHED_MAX_FDS];
>> + sched_data_t data[VUS_SCHED_MAX_FDS];
>> + int quit;
>> +} sched_t;
>> +
>> +typedef struct iscsi_lun {
>> + struct iscsi_context *iscsi_ctx;
>> + int iscsi_lun;
>> +} iscsi_lun_t;
>> +
>> +typedef struct vhost_scsi_dev {
>> + VuDev vu_dev;
>> + int server_sock;
>> + sched_t sched;
>> + iscsi_lun_t luns[VDEV_SCSI_MAX_LUNS];
>> +} vhost_scsi_dev_t;
>> +
>> +static vhost_scsi_dev_t *vhost_scsi_devs[VDEV_SCSI_MAX_DEVS];
>> +
>> +static vhost_scsi_dev_t *vdev_scsi_find_by_vu(VuDev *vu_dev);
>> +
>> +/** poll-based scheduler for libvhost-user and misc callbacks **/
>> +
>> +static int sched_add(sched_t *sched, int fd, short int evt,
>> + vu_watch_cb cb1, misc_cb cb2, void *pvt) {
>> + int i;
>> +
>> + assert(sched);
>> + assert(fd >= 0);
>> + assert(evt);
>> + assert(cb1 || cb2);
>> + assert(!(cb1 && cb2)); // only one of the cbs should be used
>> +
>> + for (i=0; i<sched->nfds && i<VUS_SCHED_MAX_FDS; i++) {
>> + if (sched->fds[i].fd == fd) {
>> + break;
>> + }
>> + }
>> + if (i == VUS_SCHED_MAX_FDS) {
>> + PERR("Error adding fd: max number of fds reached");
>> + return -1;
>> + }
>> +
>> + sched->fds[i].fd = fd;
>> + sched->fds[i].events = evt;
>> + sched->data[i].cb1 = cb1;
>> + sched->data[i].cb2 = cb2;
>> + sched->data[i].pvt = pvt;
>> + sched->data[i].evt = evt;
>> +
>> + if (sched->nfds <= i) {
>> + sched->nfds = i+1;
>> + }
>> +
>> + PDBG("address@hidden: add fd %d to slot %i", sched, fd, i);
>> +
>> + return 0;
>> +}
>> +
>> +static int sched_del(sched_t *sched, int fd) {
>> + int i;
>> +
>> + assert(sched);
>> + assert(fd >= 0);
>> +
>> + for (i=0; i<sched->nfds; i++) {
>> + if (sched->fds[i].fd == fd) {
>> + break;
>> + }
>> + }
>> + if (sched->nfds == i) {
>> +#ifdef VUS_PEDANTIC_SCHEDULER
>> + PERR("Error deleting fd %d: fd not found", fd);
>> + return -1;
>> +#else
>> + return 0;
>> +#endif
>> + }
>> +
>> + sched->nfds--;
>> + if (sched->nfds > 0) {
>> + // Overwrite deleted entry with last entry from scheduler
>> + memcpy(&sched->fds[i], &sched->fds[sched->nfds],
>> + sizeof(struct pollfd));
>> + memcpy(&sched->data[i], &sched->data[sched->nfds],
>> + sizeof(sched_data_t));
>> + }
>> + memset(&sched->fds[sched->nfds], 0, sizeof(struct pollfd));
>> + memset(&sched->data[sched->nfds], 0, sizeof(sched_data_t));
>> +
>> + PDBG("address@hidden: del fd %d from slot %i", sched, fd, i);
>> +
>> + return 0;
>> +}
>> +
>> +static int sched_loop(sched_t *sched) {
>> + int i, n;
>> +
>> + assert(sched);
>> + assert(sched->nfds > 0);
>> +
>> + while (!sched->quit) {
>> + n = poll(sched->fds, sched->nfds, -1);
>> + if (n < 0) {
>> + PERR("Error polling: %s", strerror(errno));
>> + return -1;
>> + }
>> +
>> + for (i=0; i<sched->nfds && n; i++) {
>> + if (sched->fds[i].revents != 0) {
>> +
>> + if (sched->data[i].cb1) {
>> + int vu_evt = 0;
>> +
>> + if (sched->fds[i].revents & POLLIN) vu_evt |=
>> VU_WATCH_IN;
>> + if (sched->fds[i].revents & POLLOUT) vu_evt |=
>> VU_WATCH_OUT;
>> + if (sched->fds[i].revents & POLLPRI) vu_evt |=
>> VU_WATCH_PRI;
>> + if (sched->fds[i].revents & POLLERR) vu_evt |=
>> VU_WATCH_ERR;
>> + if (sched->fds[i].revents & POLLHUP) vu_evt |=
>> VU_WATCH_HUP;
>> +
>> + PDBG("address@hidden: fd[%d] (%d): cb1(%p, %d, %p)",
>> sched, i,
>> + sched->fds[i].fd, sched->vu_dev, vu_evt,
>> + sched->data[i].pvt);
>> +
>> + sched->data[i].cb1(sched->vu_dev, vu_evt,
>> + sched->data[i].pvt);
>> + } else {
>> + PDBG("address@hidden: fd[%d] (%d): cbb(%hd, %p)",
>> sched, i,
>> + sched->fds[i].fd, sched->fds[i].revents,
>> + sched->data[i].pvt);
>> +
>> + sched->data[i].cb2(sched->fds[i].revents,
>> + sched->data[i].pvt);
>> + }
>> +
>> + n--;
>> + }
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +/** from libiscsi's scsi-lowlevel.h **/
>> +
>> +#define SCSI_CDB_MAX_SIZE 16
>> +
>> +struct scsi_iovector {
>> + struct scsi_iovec *iov;
>> + int niov;
>> + int nalloc;
>> + size_t offset;
>> + int consumed;
>> +};
>> +
>> +struct scsi_allocated_memory {
>> + struct scsi_allocated_memory *next;
>> + char buf[0];
>> +};
>> +
>> +struct scsi_data {
>> + int size;
>> + unsigned char *data;
>> +};
>> +
>> +enum scsi_sense_key {
>> + SCSI_SENSE_NO_SENSE = 0x00,
>> + SCSI_SENSE_RECOVERED_ERROR = 0x01,
>> + SCSI_SENSE_NOT_READY = 0x02,
>> + SCSI_SENSE_MEDIUM_ERROR = 0x03,
>> + SCSI_SENSE_HARDWARE_ERROR = 0x04,
>> + SCSI_SENSE_ILLEGAL_REQUEST = 0x05,
>> + SCSI_SENSE_UNIT_ATTENTION = 0x06,
>> + SCSI_SENSE_DATA_PROTECTION = 0x07,
>> + SCSI_SENSE_BLANK_CHECK = 0x08,
>> + SCSI_SENSE_VENDOR_SPECIFIC = 0x09,
>> + SCSI_SENSE_COPY_ABORTED = 0x0a,
>> + SCSI_SENSE_COMMAND_ABORTED = 0x0b,
>> + SCSI_SENSE_OBSOLETE_ERROR_CODE = 0x0c,
>> + SCSI_SENSE_OVERFLOW_COMMAND = 0x0d,
>> + SCSI_SENSE_MISCOMPARE = 0x0e
>> +};
>> +
>> +struct scsi_sense {
>> + unsigned char error_type;
>> + enum scsi_sense_key key;
>> + int ascq;
>> + unsigned sense_specific:1;
>> + unsigned ill_param_in_cdb:1;
>> + unsigned bit_pointer_valid:1;
>> + unsigned char bit_pointer;
>> + uint16_t field_pointer;
>> +};
>> +
>> +enum scsi_residual {
>> + SCSI_RESIDUAL_NO_RESIDUAL = 0,
>> + SCSI_RESIDUAL_UNDERFLOW,
>> + SCSI_RESIDUAL_OVERFLOW
>> +};
>> +
>> +struct scsi_task {
>> + int status;
>> + int cdb_size;
>> + int xfer_dir;
>> + int expxferlen;
>> + unsigned char cdb[SCSI_CDB_MAX_SIZE];
>> + enum scsi_residual residual_status;
>> + size_t residual;
>> + struct scsi_sense sense;
>> + struct scsi_data datain;
>> + struct scsi_allocated_memory *mem;
>> + void *ptr;
>> +
>> + uint32_t itt;
>> + uint32_t cmdsn;
>> + uint32_t lun;
>> +
>> + struct scsi_iovector iovector_in;
>> + struct scsi_iovector iovector_out;
>> +};
>> +
>> +/** libiscsi integration **/
>> +
>> +static int iscsi_add_lun(iscsi_lun_t *lun, char *iscsi_uri) {
>> + struct iscsi_url *iscsi_url;
>> + struct iscsi_context *iscsi_ctx;
>> + int ret = 0;
>> +
>> + assert(lun);
>> +
>> + iscsi_ctx = iscsi_create_context(ISCSI_INITIATOR);
>> + if (!iscsi_ctx) {
>> + PERR("Unable to create iSCSI context");
>> + return -1;
>> + }
>> +
>> + iscsi_url = iscsi_parse_full_url(iscsi_ctx, iscsi_uri);
>> + if (!iscsi_url) {
>> + PERR("Unable to parse iSCSI URL: %s", iscsi_get_error(iscsi_ctx));
>> + goto fail;
>> + }
>> +
>> + iscsi_set_session_type(iscsi_ctx, ISCSI_SESSION_NORMAL);
>> + iscsi_set_header_digest(iscsi_ctx, ISCSI_HEADER_DIGEST_NONE_CRC32C);
>> + if (iscsi_full_connect_sync(iscsi_ctx, iscsi_url->portal,
>> iscsi_url->lun)) {
>> + PERR("Unable to login to iSCSI portal: %s",
>> iscsi_get_error(iscsi_ctx));
>> + goto fail;
>> + }
>> +
>> + lun->iscsi_ctx = iscsi_ctx;
>> + lun->iscsi_lun = iscsi_url->lun;
>> +
>> + PDBG("Context %p created for lun 0: %s", iscsi_ctx, iscsi_uri);
>> +
>> +out:
>> + if (iscsi_url) {
>> + iscsi_destroy_url(iscsi_url);
>> + }
>> + return ret;
>> +
>> +fail:
>> + (void)iscsi_destroy_context(iscsi_ctx);
>> + ret = -1;
>> + goto out;
>> +}
>> +
>> +static struct scsi_task *scsi_task_new(int cdb_len, uint8_t *cdb, int dir,
>> + int xfer_len) {
>> + struct scsi_task *task;
>> +
>> + assert(cdb_len > 0);
>> + assert(cdb);
>> +
>> + task = calloc(1, sizeof(struct scsi_task));
>> + if (!task) {
>> + PERR("Error allocating task: %s", strerror(errno));
>> + return NULL;
>> + }
>> +
>> + memcpy(task->cdb, cdb, cdb_len);
>> + task->cdb_size = cdb_len;
>> + task->xfer_dir = dir;
>> + task->expxferlen = xfer_len;
>> +
>> + return task;
>> +}
>> +
>> +static int get_cdb_len(uint8_t *cdb) {
>> + switch(cdb[0] >> 5){
>> + case 0:
>> + return 6;
>> + case 1:
>> + case 2:
>> + return 10;
>> + case 4:
>> + return 16;
>> + case 5:
>> + return 12;
>> + }
>> + PERR("Unable to determine cdb len (0x%02hhX)", cdb[0]>>5);
>> + return -1;
>> +}
>> +
>> +static int handle_cmd_sync(struct iscsi_context *ctx,
>> + VirtIOSCSICmdReq *req,
>> + struct iovec *out, unsigned int out_len,
>> + VirtIOSCSICmdResp *rsp,
>> + struct iovec *in, unsigned int in_len) {
>> + struct scsi_task *task;
>> + uint32_t dir;
>> + uint32_t len;
>> + int cdb_len;
>> + int i;
>> +
>> + if (!((!req->lun[1]) && (req->lun[2] == 0x40) && (!req->lun[3]))) {
>> + // Ignore anything different than target=0, lun=0
>> + PDBG("Ignoring unconnected lun (0x%hhX, 0x%hhX)",
>> + req->lun[1], req->lun[3]);
>> + rsp->status = SCSI_STATUS_CHECK_CONDITION;
>> + memset(rsp->sense, 0, sizeof(rsp->sense));
>> + rsp->sense_len = 18;
>> + rsp->sense[0] = 0x70;
>> + rsp->sense[2] = 0x05; // ILLEGAL_REQUEST
>> + rsp->sense[7] = 10;
>> + rsp->sense[12] = 0x24;
>> +
>> + return 0;
>> + }
>> +
>> + cdb_len = get_cdb_len(req->cdb);
>> + if (cdb_len == -1) {
>> + return -1;
>> + }
>> +
>> + len = 0;
>> + if (!out_len && !in_len) {
>> + dir = SCSI_XFER_NONE;
>> + } else if (out_len) {
>> + dir = SCSI_XFER_TO_DEV;
>> + for (i=0; i<out_len; i++) {
>> + len += out[i].iov_len;
>> + }
>> + } else {
>> + dir = SCSI_XFER_FROM_DEV;
>> + for (i=0; i<in_len; i++) {
>> + len += in[i].iov_len;
>> + }
>> + }
>> +
>> + task = scsi_task_new(cdb_len, req->cdb, dir, len);
>> + if (!task) {
>> + PERR("Unable to create iscsi task");
>> + return -1;
>> + }
>> +
>> + if (dir == SCSI_XFER_TO_DEV) {
>> + task->iovector_out.iov = (struct scsi_iovec *)out;
>> + task->iovector_out.niov = out_len;
>> + } else if (dir == SCSI_XFER_FROM_DEV) {
>> + task->iovector_in.iov = (struct scsi_iovec *)in;
>> + task->iovector_in.niov = in_len;
>> + }
>> +
>> + PDBG("Sending iscsi cmd (cdb_len=%d, dir=%d, task=%p)",
>> + cdb_len, dir, task);
>> + if (!iscsi_scsi_command_sync(ctx, 0, task, NULL)) {
>> + PERR("Error serving SCSI command");
>> + free(task);
>> + return -1;
>> + }
>> +
>> + memset(rsp, 0, sizeof(*rsp));
>> +
>> + rsp->status = task->status;
>> + rsp->resid = task->residual;
>> +
>> + if (task->status == SCSI_STATUS_CHECK_CONDITION) {
>> + rsp->response = VIRTIO_SCSI_S_FAILURE;
>> + rsp->sense_len = task->datain.size - 2;
>> + memcpy(rsp->sense, &task->datain.data[2], rsp->sense_len);
>> + }
>> +
>> + free(task);
>> +
>> + PDBG("Filled in rsp: status=%hhX, resid=%u, response=%hhX,
>> sense_len=%u",
>> + rsp->status, rsp->resid, rsp->response, rsp->sense_len);
>> +
>> + return 0;
>> +}
>> +
>> +/** libvhost-user callbacks **/
>> +
>> +static void vus_panic_cb(VuDev *vu_dev, const char *buf) {
>> + vhost_scsi_dev_t *vdev_scsi;
>> +
>> + assert(vu_dev);
>> +
>> + vdev_scsi = vdev_scsi_find_by_vu(vu_dev);
>> +
>> + if (buf) {
>> + PERR("vu_panic: %s", buf);
>> + }
>> +
>> + if (vdev_scsi) {
>> + vdev_scsi->sched.quit = 1;
>> + }
>> +}
>> +
>> +static void vus_add_watch_cb(VuDev *vu_dev, int fd, int vu_evt, vu_watch_cb
>> cb,
>> + void *pvt) {
>> + vhost_scsi_dev_t *vdev_scsi;
>> + int poll_evt = 0;
>> +
>> + assert(vu_dev);
>> + assert(fd >= 0);
>> + assert(cb);
>> +
>> + vdev_scsi = vdev_scsi_find_by_vu(vu_dev);
>> + if (!vdev_scsi) {
>> + vus_panic_cb(vu_dev, NULL);
>> + }
>> +
>> + /* TODO: VU_WATCH_* should match POLL*, check it */
>> + if (vu_evt & VU_WATCH_IN) poll_evt |= POLLIN;
>> + if (vu_evt & VU_WATCH_OUT) poll_evt |= POLLOUT;
>> + if (vu_evt & VU_WATCH_PRI) poll_evt |= POLLPRI;
>> + if (vu_evt & VU_WATCH_ERR) poll_evt |= POLLERR;
>> + if (vu_evt & VU_WATCH_HUP) poll_evt |= POLLHUP;
>> +
>> + if (sched_add(&vdev_scsi->sched, fd, poll_evt, cb, NULL, pvt)) {
>> + vus_panic_cb(vu_dev, NULL);
>> + }
>> +}
>> +
>> +static void vus_del_watch_cb(VuDev *vu_dev, int fd) {
>> + vhost_scsi_dev_t *vdev_scsi;
>> +
>> + assert(vu_dev);
>> + assert(fd >= 0);
>> +
>> + vdev_scsi = vdev_scsi_find_by_vu(vu_dev);
>> + if (!vdev_scsi) {
>> + vus_panic_cb(vu_dev, NULL);
>> + return;
>> + }
>> +
>> + if (sched_del(&vdev_scsi->sched, fd)) {
>> + vus_panic_cb(vu_dev, NULL);
>> + }
>> +}
>> +
>> +static void vus_proc_ctl(VuDev *vu_dev, int idx) {
>> + /* Control VQ not implemented */
>> +}
>> +
>> +static void vus_proc_evt(VuDev *vu_dev, int idx) {
>> + /* Event VQ not implemented */
>> +}
>> +
>> +static void vus_proc_req(VuDev *vu_dev, int idx) {
>> + vhost_scsi_dev_t *vdev_scsi;
>> + VuVirtq *vq;
>> +
>> + assert(vu_dev);
>> +
>> + vdev_scsi = vdev_scsi_find_by_vu(vu_dev);
>> + if (!vdev_scsi) {
>> + vus_panic_cb(vu_dev, NULL);
>> + return;
>> + }
>> +
>> + if ((idx < 0) || (idx >= VHOST_MAX_NR_VIRTQUEUE)) {
>> + PERR("VQ Index out of range: %d", idx);
>> + vus_panic_cb(vu_dev, NULL);
>> + return;
>> + }
>> +
>> + vq = vu_get_queue(vu_dev, idx);
>> + if (!vq) {
>> + PERR("Error fetching VQ (dev=%p, idx=%d)", vu_dev, idx);
>> + vus_panic_cb(vu_dev, NULL);
>> + return;
>> + }
>> +
>> + PDBG("Got kicked on address@hidden", idx, vq);
>> +
>> + while(1) {
>> + VuVirtqElement *elem;
>> + VirtIOSCSICmdReq *req;
>> + VirtIOSCSICmdResp *rsp;
>> +
>> + elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement));
>> + if (!elem) {
>> + PDBG("No more elements pending on address@hidden", idx, vq);
>> + break;
>> + }
>> + PDBG("Popped address@hidden", elem);
>> +
>> + assert(!((elem->out_num > 1) && (elem->in_num > 1)));
>> + assert((elem->out_num > 0) && (elem->in_num > 0));
>> +
>> + if (elem->out_sg[0].iov_len < sizeof(VirtIOSCSICmdReq)) {
>> + PERR("Invalid virtio-scsi req header");
>> + vus_panic_cb(vu_dev, NULL);
>> + break;
>> + }
>> + req = (VirtIOSCSICmdReq *)elem->out_sg[0].iov_base;
>> +
>> + if (elem->in_sg[0].iov_len < sizeof(VirtIOSCSICmdResp)) {
>> + PERR("Invalid virtio-scsi rsp header");
>> + vus_panic_cb(vu_dev, NULL);
>> + break;
>> + }
>> + rsp = (VirtIOSCSICmdResp *)elem->in_sg[0].iov_base;
>> +
>> + if (handle_cmd_sync(vdev_scsi->luns[0].iscsi_ctx,
>> + req, &elem->out_sg[1], elem->out_num-1,
>> + rsp, &elem->in_sg[1], elem->in_num-1) != 0) {
>> + vus_panic_cb(vu_dev, NULL);
>> + break;
>> + }
>> +
>> + vu_queue_push(vu_dev, vq, elem, 0);
>> + vu_queue_notify(vu_dev, vq);
>> +
>> + free(elem);
>> + }
>> +
>> +}
>> +
>> +static void vus_queue_set_started(VuDev *vu_dev, int idx, bool started) {
>> + VuVirtq *vq;
>> +
>> + assert(vu_dev);
>> +
>> + if ((idx < 0) || (idx >= VHOST_MAX_NR_VIRTQUEUE)) {
>> + PERR("VQ Index out of range: %d", idx);
>> + vus_panic_cb(vu_dev, NULL);
>> + return;
>> + }
>> +
>> + vq = vu_get_queue(vu_dev, idx);
>> +
>> + switch(idx) {
>> + case 0:
>> + vu_set_queue_handler(vu_dev, vq, started?vus_proc_ctl:NULL);
>> + break;
>> + case 1:
>> + vu_set_queue_handler(vu_dev, vq, started?vus_proc_evt:NULL);
>> + break;
>> + default:
>> + vu_set_queue_handler(vu_dev, vq, started?vus_proc_req:NULL);
>> + }
>> +}
>> +
>> +static const VuDevIface vus_iface = {
>> + .queue_set_started = vus_queue_set_started,
>> +};
>> +
>> +static void vus_vhost_cb(VuDev *vu_dev, int vu_evt, void *data) {
>> + assert(vu_dev);
>> +
>> + if (!vu_dispatch(vu_dev) != 0) {
>> + PERR("Error processing vhost message");
>> + vus_panic_cb(vu_dev, NULL);
>> + }
>> +}
>> +
>> +/** util **/
>> +
>> +static int unix_sock_new(char *unix_fn) {
>> + int sock;
>> + struct sockaddr_un un;
>> + size_t len;
>> +
>> + assert(unix_fn);
>> +
>> + sock = socket(AF_UNIX, SOCK_STREAM, 0);
>> + if (sock <= 0) {
>> + perror("socket");
>> + return -1;
>> + }
>> +
>> + un.sun_family = AF_UNIX;
>> + (void)snprintf(un.sun_path, sizeof(un.sun_path), "%s", unix_fn);
>> + len = sizeof(un.sun_family) + strlen(un.sun_path);
>> +
>> + (void)unlink(unix_fn);
>> + if (bind(sock, (struct sockaddr *)&un, len) < 0) {
>> + perror("bind");
>> + goto fail;
>> + }
>> +
>> + if (listen(sock, 1) < 0) {
>> + perror("listen");
>> + goto fail;
>> + }
>> +
>> + return sock;
>> +
>> +fail:
>> + (void)close(sock);
>> +
>> + return -1;
>> +}
>> +
>> +/** vhost-user-scsi **/
>> +
>> +static vhost_scsi_dev_t *vdev_scsi_find_by_vu(VuDev *vu_dev) {
>> + int i;
>> +
>> + assert(vu_dev);
>> +
>> + for (i=0; i<VDEV_SCSI_MAX_DEVS; i++) {
>> + if (&vhost_scsi_devs[i]->vu_dev == vu_dev) {
>> + return vhost_scsi_devs[i];
>> + }
>> + }
>> +
>> + PERR("Unknown VuDev %p", vu_dev);
>> + return NULL;
>> +}
>> +
>> +static void vdev_scsi_deinit(vhost_scsi_dev_t *vdev_scsi) {
>> + if (!vdev_scsi) {
>> + return;
>> + }
>> +
>> + if (vdev_scsi->server_sock >= 0) {
>> + struct sockaddr_storage ss;
>> + socklen_t sslen = sizeof(ss);
>> +
>> + if (getsockname(vdev_scsi->server_sock, (struct sockaddr *)&ss,
>> + &sslen) == 0) {
>> + struct sockaddr_un *su = (struct sockaddr_un *)&ss;
>> + (void)unlink(su->sun_path);
>> + }
>> +
>> + (void)close(vdev_scsi->server_sock);
>> + }
>> +}
>> +
>> +static vhost_scsi_dev_t *vdev_scsi_new(char *unix_fn) {
>> + vhost_scsi_dev_t *vdev_scsi;
>> +
>> + assert(unix_fn);
>> +
>> + vdev_scsi = calloc(1, sizeof(vhost_scsi_dev_t));
>> + if (!vdev_scsi) {
>> + perror("calloc");
>> + return NULL;
>> + }
>> +
>> + vdev_scsi->server_sock = unix_sock_new(unix_fn);
>> + if (vdev_scsi->server_sock < 0) {
>> + free(vdev_scsi);
>> + return NULL;
>> + }
>> +
>> + vdev_scsi->sched.vu_dev = &vdev_scsi->vu_dev;
>> +
>> + return vdev_scsi;
>> +}
>> +
>> +static int vdev_scsi_iscsi_add_lun(vhost_scsi_dev_t *vdev_scsi,
>> + char *iscsi_uri, uint32_t lun) {
>> + assert(vdev_scsi);
>> + assert(iscsi_uri);
>> + assert(lun < VDEV_SCSI_MAX_LUNS);
>> +
>> + if (vdev_scsi->luns[lun].iscsi_ctx) {
>> + PERR("Lun %d already configured", lun);
>> + return -1;
>> + }
>> +
>> + if (iscsi_add_lun(&vdev_scsi->luns[lun], iscsi_uri) != 0) {
>> + return -1;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int vdev_scsi_run(vhost_scsi_dev_t *vdev_scsi) {
>> + int cli_sock;
>> + int ret = 0;
>> +
>> + assert(vdev_scsi);
>> + assert(vdev_scsi->server_sock >= 0);
>> +
>> + cli_sock = accept(vdev_scsi->server_sock, (void *)0, (void *)0);
>> + if (cli_sock < 0) {
>> + perror("accept");
>> + return -1;
>> + }
>> +
>> + vu_init(&vdev_scsi->vu_dev,
>> + cli_sock,
>> + vus_panic_cb,
>> + vus_add_watch_cb,
>> + vus_del_watch_cb,
>> + &vus_iface);
>> +
>> + ret = sched_add(&vdev_scsi->sched, cli_sock, POLLIN, vus_vhost_cb,
>> NULL, 0);
>> + if (ret) {
>> + goto fail;
>> + }
>> +
>> + if (sched_loop(&vdev_scsi->sched) != 0) {
>> + goto fail;
>> + }
>> +
>> +out:
>> + vu_deinit(&vdev_scsi->vu_dev);
>> +
>> + return ret;
>> +
>> +fail:
>> + ret = -1;
>> + goto out;
>> +}
>> +
>> +int main(int argc, char **argv)
>> +{
>> + vhost_scsi_dev_t *vdev_scsi = NULL;
>> + char *unix_fn = NULL;
>> + char *iscsi_uri = NULL;
>> + int opt, err = EXIT_SUCCESS;
>> +
>> + while ((opt = getopt(argc, argv, "u:i:")) != -1) {
>> + switch (opt) {
>> + case 'h':
>> + goto help;
>> + case 'u':
>> + unix_fn = strdup(optarg);
>> + break;
>> + case 'i':
>> + iscsi_uri = strdup(optarg);
>> + break;
>> + default:
>> + goto help;
>> + }
>> + }
>> + if (!unix_fn || !iscsi_uri) {
>> + goto help;
>> + }
>> +
>> + vdev_scsi = vdev_scsi_new(unix_fn);
>> + if (!vdev_scsi) {
>> + goto err;
>> + }
>> + vhost_scsi_devs[0] = vdev_scsi;
>> +
>> + if (vdev_scsi_iscsi_add_lun(vdev_scsi, iscsi_uri, 0) != 0) {
>> + goto err;
>> + }
>> +
>> + if (vdev_scsi_run(vdev_scsi) != 0) {
>> + goto err;
>> + }
>> +
>> +out:
>> + if (vdev_scsi) {
>> + vdev_scsi_deinit(vdev_scsi);
>> + free(vdev_scsi);
>> + }
>> + if (unix_fn) {
>> + free(unix_fn);
>> + }
>> + if (iscsi_uri) {
>> + free(iscsi_uri);
>> + }
>> +
>> + return err;
>> +
>> +err:
>> + err = EXIT_FAILURE;
>> + goto out;
>> +
>> +help:
>> + fprintf(stderr, "Usage: %s [ -u unix_sock_path -i iscsi_uri ] | [ -h
>> ]\n",
>> + argv[0]);
>> + fprintf(stderr, " -u path to unix socket\n");
>> + fprintf(stderr, " -i iscsi uri for lun 0\n");
>> + fprintf(stderr, " -h print help and quit\n");
>> +
>> + goto err;
>> +}
>>