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authorAlexey Kardashevskiy <aik@ozlabs.ru>2013-07-18 14:32:59 -0500
committerAnthony Liguori <aliguori@us.ibm.com>2013-07-29 10:37:08 -0500
commit8ca8a17c9a16eb3b2fedb3c74687c429e9cfc6aa (patch)
tree029df6f90eaa71ba5e2a8895917ae970462c2b93 /hw
parenta83000f5e3fac30a7f213af1ba6a8f827622854d (diff)
pseries: rework PAPR virtual SCSI
The patch reimplements handling of indirect requests in order to simplify upcoming live migration support. - all pointers (except SCSIRequest*) were replaces with integer indexes and offsets; - DMA'ed srp_direct_buf kept untouched (ie. BE format); - vscsi_fetch_desc() is added, now it is the only place where descriptors are fetched and byteswapped; - vscsi_req struct fields converted to migration-friendly types; - many dprintf()'s fixed. This also removed an unused field 'lun' from the spapr_vscsi device which is assigned, but never used. So, remove it. [David Gibson: removed unused 'lun'] Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Message-id: 1374175984-8930-7-git-send-email-aliguori@us.ibm.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'hw')
-rw-r--r--hw/scsi/spapr_vscsi.c223
1 files changed, 130 insertions, 93 deletions
diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c
index 55b44b9910..b0858e9299 100644
--- a/hw/scsi/spapr_vscsi.c
+++ b/hw/scsi/spapr_vscsi.c
@@ -75,20 +75,19 @@ typedef struct vscsi_req {
/* SCSI request tracking */
SCSIRequest *sreq;
uint32_t qtag; /* qemu tag != srp tag */
- int lun;
- int active;
- long data_len;
- int writing;
- int senselen;
+ bool active;
+ uint32_t data_len;
+ bool writing;
+ uint32_t senselen;
uint8_t sense[SCSI_SENSE_BUF_SIZE];
/* RDMA related bits */
uint8_t dma_fmt;
- struct srp_direct_buf ext_desc;
- struct srp_direct_buf *cur_desc;
- struct srp_indirect_buf *ind_desc;
- int local_desc;
- int total_desc;
+ uint16_t local_desc;
+ uint16_t total_desc;
+ uint16_t cdb_offset;
+ uint16_t cur_desc_num;
+ uint16_t cur_desc_offset;
} vscsi_req;
#define TYPE_VIO_SPAPR_VSCSI_DEVICE "spapr-vscsi"
@@ -264,93 +263,138 @@ static int vscsi_send_rsp(VSCSIState *s, vscsi_req *req,
return 0;
}
-static inline void vscsi_swap_desc(struct srp_direct_buf *desc)
+static inline struct srp_direct_buf vscsi_swap_desc(struct srp_direct_buf desc)
{
- desc->va = be64_to_cpu(desc->va);
- desc->len = be32_to_cpu(desc->len);
+ desc.va = be64_to_cpu(desc.va);
+ desc.len = be32_to_cpu(desc.len);
+ return desc;
+}
+
+static int vscsi_fetch_desc(VSCSIState *s, struct vscsi_req *req,
+ unsigned n, unsigned buf_offset,
+ struct srp_direct_buf *ret)
+{
+ struct srp_cmd *cmd = &req->iu.srp.cmd;
+
+ switch (req->dma_fmt) {
+ case SRP_NO_DATA_DESC: {
+ dprintf("VSCSI: no data descriptor\n");
+ return 0;
+ }
+ case SRP_DATA_DESC_DIRECT: {
+ memcpy(ret, cmd->add_data + req->cdb_offset, sizeof(*ret));
+ assert(req->cur_desc_num == 0);
+ dprintf("VSCSI: direct segment\n");
+ break;
+ }
+ case SRP_DATA_DESC_INDIRECT: {
+ struct srp_indirect_buf *tmp = (struct srp_indirect_buf *)
+ (cmd->add_data + req->cdb_offset);
+ if (n < req->local_desc) {
+ *ret = tmp->desc_list[n];
+ dprintf("VSCSI: indirect segment local tag=0x%x desc#%d/%d\n",
+ req->qtag, n, req->local_desc);
+
+ } else if (n < req->total_desc) {
+ int rc;
+ struct srp_direct_buf tbl_desc = vscsi_swap_desc(tmp->table_desc);
+ unsigned desc_offset = n * sizeof(struct srp_direct_buf);
+
+ if (desc_offset >= tbl_desc.len) {
+ dprintf("VSCSI: #%d is ouf of range (%d bytes)\n",
+ n, desc_offset);
+ return -1;
+ }
+ rc = spapr_vio_dma_read(&s->vdev, tbl_desc.va + desc_offset,
+ ret, sizeof(struct srp_direct_buf));
+ if (rc) {
+ dprintf("VSCSI: spapr_vio_dma_read -> %d reading ext_desc\n",
+ rc);
+ return -1;
+ }
+ dprintf("VSCSI: indirect segment ext. tag=0x%x desc#%d/%d { va=%"PRIx64" len=%x }\n",
+ req->qtag, n, req->total_desc, tbl_desc.va, tbl_desc.len);
+ } else {
+ dprintf("VSCSI: Out of descriptors !\n");
+ return 0;
+ }
+ break;
+ }
+ default:
+ fprintf(stderr, "VSCSI: Unknown format %x\n", req->dma_fmt);
+ return -1;
+ }
+
+ *ret = vscsi_swap_desc(*ret);
+ if (buf_offset > ret->len) {
+ dprintf(" offset=%x is out of a descriptor #%d boundary=%x\n",
+ buf_offset, req->cur_desc_num, ret->len);
+ return -1;
+ }
+ ret->va += buf_offset;
+ ret->len -= buf_offset;
+
+ dprintf(" cur=%d offs=%x ret { va=%"PRIx64" len=%x }\n",
+ req->cur_desc_num, req->cur_desc_offset, ret->va, ret->len);
+
+ return ret->len ? 1 : 0;
}
static int vscsi_srp_direct_data(VSCSIState *s, vscsi_req *req,
uint8_t *buf, uint32_t len)
{
- struct srp_direct_buf *md = req->cur_desc;
+ struct srp_direct_buf md;
uint32_t llen;
int rc = 0;
- dprintf("VSCSI: direct segment 0x%x bytes, va=0x%llx desc len=0x%x\n",
- len, (unsigned long long)md->va, md->len);
+ rc = vscsi_fetch_desc(s, req, req->cur_desc_num, req->cur_desc_offset, &md);
+ if (rc < 0) {
+ return -1;
+ } else if (rc == 0) {
+ return 0;
+ }
- llen = MIN(len, md->len);
+ llen = MIN(len, md.len);
if (llen) {
if (req->writing) { /* writing = to device = reading from memory */
- rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
+ rc = spapr_vio_dma_read(&s->vdev, md.va, buf, llen);
} else {
- rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
+ rc = spapr_vio_dma_write(&s->vdev, md.va, buf, llen);
}
}
- md->len -= llen;
- md->va += llen;
if (rc) {
return -1;
}
+ req->cur_desc_offset += llen;
+
return llen;
}
static int vscsi_srp_indirect_data(VSCSIState *s, vscsi_req *req,
uint8_t *buf, uint32_t len)
{
- struct srp_direct_buf *td = &req->ind_desc->table_desc;
- struct srp_direct_buf *md = req->cur_desc;
+ struct srp_direct_buf md;
int rc = 0;
uint32_t llen, total = 0;
- dprintf("VSCSI: indirect segment 0x%x bytes, td va=0x%llx len=0x%x\n",
- len, (unsigned long long)td->va, td->len);
+ dprintf("VSCSI: indirect segment 0x%x bytes\n", len);
/* While we have data ... */
while (len) {
- /* If we have a descriptor but it's empty, go fetch a new one */
- if (md && md->len == 0) {
- /* More local available, use one */
- if (req->local_desc) {
- md = ++req->cur_desc;
- --req->local_desc;
- --req->total_desc;
- td->va += sizeof(struct srp_direct_buf);
- } else {
- md = req->cur_desc = NULL;
- }
- }
- /* No descriptor at hand, fetch one */
- if (!md) {
- if (!req->total_desc) {
- dprintf("VSCSI: Out of descriptors !\n");
- break;
- }
- md = req->cur_desc = &req->ext_desc;
- dprintf("VSCSI: Reading desc from 0x%llx\n",
- (unsigned long long)td->va);
- rc = spapr_vio_dma_read(&s->vdev, td->va, md,
- sizeof(struct srp_direct_buf));
- if (rc) {
- dprintf("VSCSI: spapr_vio_dma_read -> %d reading ext_desc\n",
- rc);
- break;
- }
- vscsi_swap_desc(md);
- td->va += sizeof(struct srp_direct_buf);
- --req->total_desc;
+ rc = vscsi_fetch_desc(s, req, req->cur_desc_num, req->cur_desc_offset, &md);
+ if (rc < 0) {
+ return -1;
+ } else if (rc == 0) {
+ break;
}
- dprintf("VSCSI: [desc va=0x%llx,len=0x%x] remaining=0x%x\n",
- (unsigned long long)md->va, md->len, len);
/* Perform transfer */
- llen = MIN(len, md->len);
+ llen = MIN(len, md.len);
if (req->writing) { /* writing = to device = reading from memory */
- rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
+ rc = spapr_vio_dma_read(&s->vdev, md.va, buf, llen);
} else {
- rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
+ rc = spapr_vio_dma_write(&s->vdev, md.va, buf, llen);
}
if (rc) {
dprintf("VSCSI: spapr_vio_dma_r/w(%d) -> %d\n", req->writing, rc);
@@ -361,10 +405,18 @@ static int vscsi_srp_indirect_data(VSCSIState *s, vscsi_req *req,
len -= llen;
buf += llen;
+
total += llen;
- md->va += llen;
- md->len -= llen;
+
+ /* Update current position in the current descriptor */
+ req->cur_desc_offset += llen;
+ if (md.len == llen) {
+ /* Go to the next descriptor if the current one finished */
+ ++req->cur_desc_num;
+ req->cur_desc_offset = 0;
+ }
}
+
return rc ? -1 : total;
}
@@ -412,14 +464,13 @@ static int data_out_desc_size(struct srp_cmd *cmd)
static int vscsi_preprocess_desc(vscsi_req *req)
{
struct srp_cmd *cmd = &req->iu.srp.cmd;
- int offset, i;
- offset = cmd->add_cdb_len & ~3;
+ req->cdb_offset = cmd->add_cdb_len & ~3;
if (req->writing) {
req->dma_fmt = cmd->buf_fmt >> 4;
} else {
- offset += data_out_desc_size(cmd);
+ req->cdb_offset += data_out_desc_size(cmd);
req->dma_fmt = cmd->buf_fmt & ((1U << 4) - 1);
}
@@ -427,31 +478,18 @@ static int vscsi_preprocess_desc(vscsi_req *req)
case SRP_NO_DATA_DESC:
break;
case SRP_DATA_DESC_DIRECT:
- req->cur_desc = (struct srp_direct_buf *)(cmd->add_data + offset);
req->total_desc = req->local_desc = 1;
- vscsi_swap_desc(req->cur_desc);
- dprintf("VSCSI: using direct RDMA %s, 0x%x bytes MD: 0x%llx\n",
- req->writing ? "write" : "read",
- req->cur_desc->len, (unsigned long long)req->cur_desc->va);
break;
- case SRP_DATA_DESC_INDIRECT:
- req->ind_desc = (struct srp_indirect_buf *)(cmd->add_data + offset);
- vscsi_swap_desc(&req->ind_desc->table_desc);
- req->total_desc = req->ind_desc->table_desc.len /
- sizeof(struct srp_direct_buf);
+ case SRP_DATA_DESC_INDIRECT: {
+ struct srp_indirect_buf *ind_tmp = (struct srp_indirect_buf *)
+ (cmd->add_data + req->cdb_offset);
+
+ req->total_desc = be32_to_cpu(ind_tmp->table_desc.len) /
+ sizeof(struct srp_direct_buf);
req->local_desc = req->writing ? cmd->data_out_desc_cnt :
- cmd->data_in_desc_cnt;
- for (i = 0; i < req->local_desc; i++) {
- vscsi_swap_desc(&req->ind_desc->desc_list[i]);
- }
- req->cur_desc = req->local_desc ? &req->ind_desc->desc_list[0] : NULL;
- dprintf("VSCSI: using indirect RDMA %s, 0x%x bytes %d descs "
- "(%d local) VA: 0x%llx\n",
- req->writing ? "read" : "write",
- be32_to_cpu(req->ind_desc->len),
- req->total_desc, req->local_desc,
- (unsigned long long)req->ind_desc->table_desc.va);
+ cmd->data_in_desc_cnt;
break;
+ }
default:
fprintf(stderr,
"vscsi_preprocess_desc: Unknown format %x\n", req->dma_fmt);
@@ -499,8 +537,8 @@ static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status, size_t re
vscsi_req *req = sreq->hba_private;
int32_t res_in = 0, res_out = 0;
- dprintf("VSCSI: SCSI cmd complete, r=0x%x tag=0x%x status=0x%x, req=%p\n",
- reason, sreq->tag, status, req);
+ dprintf("VSCSI: SCSI cmd complete, tag=0x%x status=0x%x, req=%p\n",
+ sreq->tag, status, req);
if (req == NULL) {
fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
return;
@@ -509,7 +547,7 @@ static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status, size_t re
if (status == CHECK_CONDITION) {
req->senselen = scsi_req_get_sense(req->sreq, req->sense,
sizeof(req->sense));
- dprintf("VSCSI: Sense data, %d bytes:\n", len);
+ dprintf("VSCSI: Sense data, %d bytes:\n", req->senselen);
dprintf(" %02x %02x %02x %02x %02x %02x %02x %02x\n",
req->sense[0], req->sense[1], req->sense[2], req->sense[3],
req->sense[4], req->sense[5], req->sense[6], req->sense[7]);
@@ -621,12 +659,11 @@ static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
} return 1;
}
- req->lun = lun;
req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, req);
n = scsi_req_enqueue(req->sreq);
- dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x ID %d LUN %d ret: %d\n",
- req->qtag, srp->cmd.cdb[0], id, lun, n);
+ dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x LUN %d ret: %d\n",
+ req->qtag, srp->cmd.cdb[0], lun, n);
if (n) {
/* Transfer direction must be set before preprocessing the