iscsi/qemu-img/block-migration enhancements

Signed-off-by Peter Lieven <[email protected]>

---
 block/iscsi.c |   77 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)

block/iscsi.c +0 -0

index 0bbf0b1..ab42f1e 100644

block/iscsi.c +73 -0

 } IscsiLun;
 
 typedef struct IscsiAIOCB {

@@ -948,6 +952,8 @@ static int iscsi_readcapacity_sync(IscsiLun *iscsilun)
                 } else {
                     iscsilun->block_size = rc16->block_length;
                     iscsilun->num_blocks = rc16->returned_lba + 1;
+                    iscsilun->lbpme = rc16->lbpme;
+                    iscsilun->lbprz = rc16->lbprz;
                 }
             }
             break;

@@ -1000,6 +1006,37 @@ static QemuOptsList runtime_opts = {
     },
 };
 
+static struct scsi_task *iscsi_do_inquiry(struct iscsi_context *iscsi,
+                                          int lun, int evpd, int pc) {
+        int full_size;
+        struct scsi_task *task = NULL;
+        task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, 64);
+        if (task == NULL || task->status != SCSI_STATUS_GOOD) {
+            goto fail;
+        }
+        full_size = scsi_datain_getfullsize(task);
+        if (full_size > task->datain.size) {
+            scsi_free_scsi_task(task);
+
+            /* we need more data for the full list */
+            task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, full_size);
+            if (task == NULL || task->status != SCSI_STATUS_GOOD) {
+                goto fail;
+            }
+        }
+
+        return task;
+
+fail:
+        error_report("iSCSI: Inquiry command failed : %s",
+                     iscsi_get_error(iscsi));
+        if (task) {
+            scsi_free_scsi_task(task);
+            return NULL;
+        }
+        return NULL;
+}
+
 /*
  * We support iscsi url's on the form
  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>

@@ -1130,6 +1167,46 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags)
         bs->sg = 1;
     }
 
+    if (iscsilun->lbpme) {
+        struct scsi_inquiry_logical_block_provisioning *inq_lbp;
+        task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
+                                SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING);
+        if (task == NULL) {
+            ret = -EINVAL;
+            goto out;
+        }
+        inq_lbp = scsi_datain_unmarshall(task);
+        if (inq_lbp == NULL) {
+            error_report("iSCSI: failed to unmarshall inquiry datain blob");
+            ret = -EINVAL;
+            goto out;
+        }
+        memcpy(&iscsilun->lbp, inq_lbp,
+               sizeof(struct scsi_inquiry_logical_block_provisioning));
+        scsi_free_scsi_task(task);
+        task = NULL;
+    }
+
+    if (iscsilun->lbp.lbpu) {
+        struct scsi_inquiry_block_limits *inq_bl;
+        task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
+                                SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS);
+        if (task == NULL) {
+            ret = -EINVAL;
+            goto out;
+        }
+        inq_bl = scsi_datain_unmarshall(task);
+        if (inq_bl == NULL) {
+            error_report("iSCSI: failed to unmarshall inquiry datain blob");
+            ret = -EINVAL;
+            goto out;
+        }
+        memcpy(&iscsilun->bl, inq_bl,
+               sizeof(struct scsi_inquiry_block_limits));
+        scsi_free_scsi_task(task);
+        task = NULL;
+    }
+
 #if defined(LIBISCSI_FEATURE_NOP_COUNTER)
     /* Set up a timer for sending out iSCSI NOPs */
     iscsilun->nop_timer = qemu_new_timer_ms(rt_clock, iscsi_nop_timed_event, iscsilun);

this patch adds a coroutine for .bdrv_co_is_allocated as well as a generic framework that can be used to build coroutines in block/iscsi.

Signed-off-by Peter Lieven <[email protected]>

---
 block/iscsi.c |  130 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)

block/iscsi.c +130 -0

index ab42f1e..56dedff 100644
@@ -55,6 +55,15 @@ 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;

@@ -110,6 +119,41 @@ 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,

@@ -804,6 +848,90 @@ iscsi_getlength(BlockDriverState *bs)
     return len;
 }
 
+static int coroutine_fn iscsi_co_is_allocated(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;
+    int ret;
+
+    /* default to all sectors allocated */
+    ret = 1;
+    *pnum = nb_sectors;
+
+    /* LUN does not support logical block provisioning */
+    if (iscsilun->lbpme == 0) {
+        goto out;
+    }
+
+    iscsi_co_init_iscsitask(iscsilun, &iTask);
+
+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 = 0;
+        *pnum = 0;
+        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 = 0;
+        *pnum = 0;
+        goto out;
+    }
+
+    lbasd = &lbas->descriptors[0];
+
+    if (sector_qemu2lun(sector_num, iscsilun) != lbasd->lba) {
+        ret = 0;
+        *pnum = 0;
+        goto out;
+    }
+
+    *pnum = lbasd->num_blocks * (iscsilun->block_size / BDRV_SECTOR_SIZE);
+    if (*pnum > nb_sectors) {
+        *pnum = nb_sectors;
+    }
+
+    if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
+        lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
+        ret = 0;
+    }
+
+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;

@@ -1345,6 +1473,8 @@ static BlockDriver bdrv_iscsi = {
     .bdrv_getlength  = iscsi_getlength,
     .bdrv_truncate   = iscsi_truncate,
 
+    .bdrv_co_is_allocated = iscsi_co_is_allocated,
+
     .bdrv_aio_readv  = iscsi_aio_readv,
     .bdrv_aio_writev = iscsi_aio_writev,
     .bdrv_aio_flush  = iscsi_aio_flush,

Il 18/07/2013 10:19, Peter Lieven ha scritto:

Quoted 2 lines

this patch adds a coroutine for .bdrv_co_is_allocated as well as a generic framework that can be used to build coroutines in block/iscsi.

This conflicts with my bdrv_get_block_status patches.

this series adds logical block provisioning functions to the iscsi layer. it also is the first step to the change of migration to coroutines in block/iscsi.

v3->v4:
- this series collapsed into 2 patches not yet merged. as per discussion write_zero optimization will be a different approach handled at the block layer.
- patch 1 will now copy the complete vpd pages as almost all fields will be needed later.

Peter Lieven (2):
iscsi: add logical block provisioning information to iscsilun
iscsi: add .bdrv_co_is_allocated

 block/iscsi.c |  207 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 207 insertions(+)