From a976099b24c5db9cb4ab1a059b01610d2fc48537 Mon Sep 17 00:00:00 2001

Message-Id: <a976099b24c5db9cb4ab1a059b01610d2fc48537.1389014116.git.minovotn@redhat.com>

In-Reply-To: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>

References: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>

From: Paolo Bonzini <pbonzini@redhat.com>

Date: Mon, 9 Dec 2013 14:08:52 +0100

Subject: [PATCH 04/50] iscsi: add .bdrv_get_block_status

RH-Author: Paolo Bonzini <pbonzini@redhat.com>

Message-id: <1386598178-11845-7-git-send-email-pbonzini@redhat.com>

Patchwork-id: 56043

O-Subject: [RHEL 7.0 qemu-kvm PATCH 06/52] iscsi: add .bdrv_get_block_status

Bugzilla: 1007815

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

From: Peter Lieven <pl@kamp.de>

this patch adds a coroutine for .bdrv_co_block_status as well as

a generic framework that can be used to build coroutines in block/iscsi.

Signed-off-by: Peter Lieven <pl@kamp.de>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

(cherry picked from commit 54a5c1d5db47b4146490937ed73e3f56022aaba6)

---

 block/iscsi.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 1 file changed, 136 insertions(+)

Signed-off-by: Michal Novotny <minovotn@redhat.com>

---

 block/iscsi.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 1 file changed, 136 insertions(+)

diff --git a/block/iscsi.c b/block/iscsi.c

index 6804b6d..f8d021a 100644

--- a/block/iscsi.c

+++ b/block/iscsi.c

@@ -58,6 +58,15 @@ typedef struct IscsiLun {

     struct scsi_inquiry_block_limits bl;

 } IscsiLun;

+typedef struct IscsiTask {

+    int status;

+    int complete;

+    int retries;

+    int do_retry;

+    struct scsi_task *task;

+    Coroutine *co;

+} IscsiTask;

+

 typedef struct IscsiAIOCB {

     BlockDriverAIOCB common;

     QEMUIOVector *qiov;

@@ -111,6 +120,41 @@ iscsi_schedule_bh(IscsiAIOCB *acb)

     qemu_bh_schedule(acb->bh);

 }

+static void

+iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,

+                        void *command_data, void *opaque)

+{

+    struct IscsiTask *iTask = opaque;

+    struct scsi_task *task = command_data;

+

+    iTask->complete = 1;

+    iTask->status = status;

+    iTask->do_retry = 0;

+    iTask->task = task;

+

+    if (iTask->retries-- > 0 && status == SCSI_STATUS_CHECK_CONDITION

+        && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {

+        iTask->do_retry = 1;

+        goto out;

+    }

+

+    if (status != SCSI_STATUS_GOOD) {

+        error_report("iSCSI: Failure. %s", iscsi_get_error(iscsi));

+    }

+

+out:

+    if (iTask->co) {

+        qemu_coroutine_enter(iTask->co, NULL);

+    }

+}

+

+static void iscsi_co_init_iscsitask(IscsiLun *iscsilun, struct IscsiTask *iTask)

+{

+    *iTask = (struct IscsiTask) {

+        .co         = qemu_coroutine_self(),

+        .retries    = ISCSI_CMD_RETRIES,

+    };

+}

 static void

 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,

@@ -854,6 +898,96 @@ iscsi_getlength(BlockDriverState *bs)

     return len;

 }

+static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,

+                                                  int64_t sector_num,

+                                                  int nb_sectors, int *pnum)

+{

+    IscsiLun *iscsilun = bs->opaque;

+    struct scsi_get_lba_status *lbas = NULL;

+    struct scsi_lba_status_descriptor *lbasd = NULL;

+    struct IscsiTask iTask;

+    int64_t ret;

+

+    iscsi_co_init_iscsitask(iscsilun, &iTask);

+

+    if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {

+        ret = -EINVAL;

+        goto out;

+    }

+

+    /* default to all sectors allocated */

+    ret = BDRV_BLOCK_DATA;

+    ret |= (sector_num << BDRV_SECTOR_BITS) | BDRV_BLOCK_OFFSET_VALID;

+    *pnum = nb_sectors;

+

+    /* LUN does not support logical block provisioning */

+    if (iscsilun->lbpme == 0) {

+        goto out;

+    }

+

+retry:

+    if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,

+                                  sector_qemu2lun(sector_num, iscsilun),

+                                  8 + 16, iscsi_co_generic_cb,

+                                  &iTask) == NULL) {

+        ret = -EIO;

+        goto out;

+    }

+

+    while (!iTask.complete) {

+        iscsi_set_events(iscsilun);

+        qemu_coroutine_yield();

+    }

+

+    if (iTask.do_retry) {

+        if (iTask.task != NULL) {

+            scsi_free_scsi_task(iTask.task);

+            iTask.task = NULL;

+        }

+        goto retry;

+    }

+

+    if (iTask.status != SCSI_STATUS_GOOD) {

+        /* in case the get_lba_status_callout fails (i.e.

+         * because the device is busy or the cmd is not

+         * supported) we pretend all blocks are allocated

+         * for backwards compatiblity */

+        goto out;

+    }

+

+    lbas = scsi_datain_unmarshall(iTask.task);

+    if (lbas == NULL) {

+        ret = -EIO;

+        goto out;

+    }

+

+    lbasd = &lbas->descriptors[0];

+

+    if (sector_qemu2lun(sector_num, iscsilun) != lbasd->lba) {

+        ret = -EIO;

+        goto out;

+    }

+

+    *pnum = sector_lun2qemu(lbasd->num_blocks, iscsilun);

+    if (*pnum > nb_sectors) {

+        *pnum = nb_sectors;

+    }

+

+    if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||

+        lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {

+        ret &= ~BDRV_BLOCK_DATA;

+        if (iscsilun->lbprz) {

+            ret |= BDRV_BLOCK_ZERO;

+        }

+    }

+

+out:

+    if (iTask.task != NULL) {

+        scsi_free_scsi_task(iTask.task);

+    }

+    return ret;

+}

+

 static int parse_chap(struct iscsi_context *iscsi, const char *target)

 {

     QemuOptsList *list;

@@ -1406,6 +1540,8 @@ static BlockDriver bdrv_iscsi = {

     .bdrv_getlength  = iscsi_getlength,

     .bdrv_truncate   = iscsi_truncate,

+    .bdrv_co_get_block_status = iscsi_co_get_block_status,

+

     .bdrv_aio_readv  = iscsi_aio_readv,

     .bdrv_aio_writev = iscsi_aio_writev,

     .bdrv_aio_flush  = iscsi_aio_flush,

-- 

1.7.11.7