WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] [PATCH 1/2] xen-unstable/blkif: Move read/write/barrier spec

To: <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [Xen-devel] [PATCH 1/2] xen-unstable/blkif: Move read/write/barrier specific fields into a union
From: <owen.smith@xxxxxxxxxx>
Date: Fri, 14 Jan 2011 16:44:22 +0000
Cc: Owen Smith <owen.smith@xxxxxxxxxx>
Delivery-date: Fri, 14 Jan 2011 08:51:04 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <1295023467-27129-1-git-send-email-owen.smith@xxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <1295023467-27129-1-git-send-email-owen.smith@xxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
From: Owen Smith <owen.smith@xxxxxxxxxx>

# HG 
changeset patch
# User root@xxxxxxxxxxxxxxxxxxxxxxx
# Date 1294919321 0
# Node ID 428420495fd3cfda164e7b355b0ffcc0845af2e4
# Parent  7b4c82f07281ad9c48b652e2a305a7be607c5283
blkif: Move read/write/barrier specific fields into a union

Patches xen-unstable.hg

Modifies the blkif ring interface by placing the request specific
fields into a union in order to support additional operation types.

Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>

diff -r 7b4c82f07281 -r 428420495fd3 extras/mini-os/blkfront.c
--- a/extras/mini-os/blkfront.c Wed Jan 05 23:54:15 2011 +0000
+++ b/extras/mini-os/blkfront.c Thu Jan 13 11:48:41 2011 +0000
@@ -361,22 +361,22 @@
     req->nr_segments = n;
     req->handle = dev->handle;
     req->id = (uintptr_t) aiocbp;
-    req->sector_number = aiocbp->aio_offset / 512;
+    req->u.rw.sector_number = aiocbp->aio_offset / 512;
 
     for (j = 0; j < n; j++) {
-        req->seg[j].first_sect = 0;
-        req->seg[j].last_sect = PAGE_SIZE / 512 - 1;
+        req->u.rw.seg[j].first_sect = 0;
+        req->u.rw.seg[j].last_sect = PAGE_SIZE / 512 - 1;
     }
-    req->seg[0].first_sect = ((uintptr_t)aiocbp->aio_buf & ~PAGE_MASK) / 512;
-    req->seg[n-1].last_sect = (((uintptr_t)aiocbp->aio_buf + 
aiocbp->aio_nbytes - 1) & ~PAGE_MASK) / 512;
+    req->u.rw.seg[0].first_sect = ((uintptr_t)aiocbp->aio_buf & ~PAGE_MASK) / 
512;
+    req->u.rw.seg[n-1].last_sect = (((uintptr_t)aiocbp->aio_buf + 
aiocbp->aio_nbytes - 1) & ~PAGE_MASK) / 512;
     for (j = 0; j < n; j++) {
        uintptr_t data = start + j * PAGE_SIZE;
         if (!write) {
             /* Trigger CoW if needed */
-            *(char*)(data + (req->seg[j].first_sect << 9)) = 0;
+            *(char*)(data + (req->u.rw.seg[j].first_sect << 9)) = 0;
             barrier();
         }
-       aiocbp->gref[j] = req->seg[j].gref =
+       aiocbp->gref[j] = req->u.rw.seg[j].gref =
             gnttab_grant_access(dev->dom, virtual_to_mfn(data), write);
     }
 
@@ -432,7 +432,7 @@
     req->handle = dev->handle;
     req->id = id;
     /* Not needed anyway, but the backend will check it */
-    req->sector_number = 0;
+    req->u.rw.sector_number = 0;
     dev->ring.req_prod_pvt = i + 1;
     wmb();
     RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&dev->ring, notify);
diff -r 7b4c82f07281 -r 428420495fd3 tools/blktap/drivers/tapdisk.c
--- a/tools/blktap/drivers/tapdisk.c    Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/blktap/drivers/tapdisk.c    Thu Jan 13 11:48:41 2011 +0000
@@ -528,10 +528,10 @@
 segment_start(blkif_request_t *req, int sidx)
 {
        int i;
-       uint64_t start = req->sector_number;
+       uint64_t start = req->u.rw.sector_number;
 
        for (i = 0; i < sidx; i++) 
-               start += (req->seg[i].last_sect - req->seg[i].first_sect + 1);
+               start += (req->u.rw.seg[i].last_sect - 
req->u.rw.seg[i].first_sect + 1);
 
        return start;
 }
@@ -600,13 +600,13 @@
        struct disk_driver *parent = dd->next;
        
        seg_start = segment_start(req, sidx);
-       seg_end   = seg_start + req->seg[sidx].last_sect + 1;
+       seg_end   = seg_start + req->u.rw.seg[sidx].last_sect + 1;
        
        ASSERT(sector >= seg_start && sector + nr_secs <= seg_end);
 
        page  = (char *)MMAP_VADDR(info->vstart, 
                                   (unsigned long)req->id, sidx);
-       page += (req->seg[sidx].first_sect << SECTOR_SHIFT);
+       page += (req->u.rw.seg[sidx].first_sect << SECTOR_SHIFT);
        page += ((sector - seg_start) << SECTOR_SHIFT);
 
        if (!parent) {
@@ -667,7 +667,7 @@
                               req, sizeof(*req));
                        blkif->pending_list[idx].status = BLKIF_RSP_OKAY;
                        blkif->pending_list[idx].submitting = 1;
-                       sector_nr = req->sector_number;
+                       sector_nr = req->u.rw.sector_number;
                }
 
                if ((dd->flags & TD_RDONLY) && 
@@ -677,16 +677,16 @@
                }
 
                for (i = start_seg; i < req->nr_segments; i++) {
-                       nsects = req->seg[i].last_sect - 
-                                req->seg[i].first_sect + 1;
+                       nsects = req->u.rw.seg[i].last_sect - 
+                                req->u.rw.seg[i].first_sect + 1;
        
-                       if ((req->seg[i].last_sect >= page_size >> 9) ||
+                       if ((req->u.rw.seg[i].last_sect >= page_size >> 9) ||
                            (nsects <= 0))
                                continue;
 
                        page  = (char *)MMAP_VADDR(info->vstart, 
                                                   (unsigned long)req->id, i);
-                       page += (req->seg[i].first_sect << SECTOR_SHIFT);
+                       page += (req->u.rw.seg[i].first_sect << SECTOR_SHIFT);
 
                        if (sector_nr >= s->size) {
                                DPRINTF("Sector request failed:\n");
diff -r 7b4c82f07281 -r 428420495fd3 tools/blktap2/drivers/tapdisk-diff.c
--- a/tools/blktap2/drivers/tapdisk-diff.c      Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/blktap2/drivers/tapdisk-diff.c      Thu Jan 13 11:48:41 2011 +0000
@@ -363,13 +363,13 @@
        breq                = &sreq->blkif_req;
        breq->id            = idx;
        breq->nr_segments   = r->blkif_req.nr_segments;
-       breq->sector_number = r->blkif_req.sector_number;
+       breq->u.rw.sector_number = r->blkif_req.u.rw.sector_number;
        breq->operation     = BLKIF_OP_READ;
 
        for (int i = 0; i < r->blkif_req.nr_segments; i++) {
-               struct blkif_request_segment *seg = breq->seg + i;
-               seg->first_sect = r->blkif_req.seg[i].first_sect;
-               seg->last_sect  = r->blkif_req.seg[i].last_sect;
+               struct blkif_request_segment *seg = breq->u.rw.seg + i;
+               seg->first_sect = r->blkif_req.u.rw.seg[i].first_sect;
+               seg->last_sect  = r->blkif_req.u.rw.seg[i].last_sect;
        }
        s->cur += sreq->secs;
 
@@ -426,12 +426,12 @@
                breq                = &sreq->blkif_req;
                breq->id            = idx;
                breq->nr_segments   = 0;
-               breq->sector_number = sreq->sec;
+               breq->u.rw.sector_number = sreq->sec;
                breq->operation     = BLKIF_OP_READ;
 
                for (i = 0; i < BLKIF_MAX_SEGMENTS_PER_REQUEST; i++) {
                        uint32_t secs;
-                       struct blkif_request_segment *seg = breq->seg + i;
+                       struct blkif_request_segment *seg = breq->u.rw.seg + i;
 
                        secs = MIN(s->end - s->cur, psize >> SECTOR_SHIFT);
                        secs = MIN(((blk + 1) << SPB_SHIFT) - s->cur, secs);
diff -r 7b4c82f07281 -r 428420495fd3 tools/blktap2/drivers/tapdisk-image.c
--- a/tools/blktap2/drivers/tapdisk-image.c     Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/blktap2/drivers/tapdisk-image.c     Thu Jan 13 11:48:41 2011 +0000
@@ -148,15 +148,15 @@
        psize = getpagesize();
 
        for (i = 0; i < req->nr_segments; i++) {
-               nsects = req->seg[i].last_sect - req->seg[i].first_sect + 1;
+               nsects = req->u.rw.seg[i].last_sect - 
req->u.rw.seg[i].first_sect + 1;
                
-               if (req->seg[i].last_sect >= psize >> 9 || nsects <= 0)
+               if (req->u.rw.seg[i].last_sect >= psize >> 9 || nsects <= 0)
                        goto fail;
 
                total += nsects;
        }
 
-       if (req->sector_number + nsects > info->size)
+       if (req->u.rw.sector_number + nsects > info->size)
                goto fail;
 
        return 0;
@@ -164,6 +164,6 @@
 fail:
        ERR(-EINVAL, "bad request on %s (%s, %"PRIu64"): id: %"PRIu64": %d at 
%"PRIu64,
            image->name, (rdonly ? "ro" : "rw"), info->size, req->id,
-           req->operation, req->sector_number + total);
+           req->operation, req->u.rw.sector_number + total);
        return -EINVAL;
 }
diff -r 7b4c82f07281 -r 428420495fd3 tools/blktap2/drivers/tapdisk-stream.c
--- a/tools/blktap2/drivers/tapdisk-stream.c    Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/blktap2/drivers/tapdisk-stream.c    Thu Jan 13 11:48:41 2011 +0000
@@ -293,12 +293,12 @@
                breq                = &sreq->blkif_req;
                breq->id            = idx;
                breq->nr_segments   = 0;
-               breq->sector_number = sreq->sec;
+               breq->u.rw.sector_number = sreq->sec;
                breq->operation     = BLKIF_OP_READ;
 
                for (i = 0; i < BLKIF_MAX_SEGMENTS_PER_REQUEST; i++) {
                        uint32_t secs = MIN(s->end - s->cur, psize >> 
SECTOR_SHIFT);
-                       struct blkif_request_segment *seg = breq->seg + i;
+                       struct blkif_request_segment *seg = breq->u.rw.seg + i;
 
                        if (!secs)
                                break;
diff -r 7b4c82f07281 -r 428420495fd3 tools/blktap2/drivers/tapdisk-vbd.c
--- a/tools/blktap2/drivers/tapdisk-vbd.c       Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/blktap2/drivers/tapdisk-vbd.c       Thu Jan 13 11:48:41 2011 +0000
@@ -1066,7 +1066,7 @@
        rsp->status = vreq->status;
 
        DBG(TLOG_DBG, "writing req %d, sec 0x%08"PRIx64", res %d to ring\n",
-           (int)tmp.id, tmp.sector_number, vreq->status);
+           (int)tmp.id, tmp.u.rw.sector_number, vreq->status);
 
        if (rsp->status != BLKIF_RSP_OKAY)
                ERR(EIO, "returning BLKIF_RSP %d", rsp->status);
@@ -1181,10 +1181,10 @@
 tapdisk_vbd_breq_get_sector(blkif_request_t *breq, td_request_t treq)
 {
     int seg, nsects; 
-    uint64_t sector_nr = breq->sector_number; 
+    uint64_t sector_nr = breq->u.rw.sector_number; 
     
     for(seg=0; seg < treq.sidx; seg++) {
-        nsects = breq->seg[seg].last_sect - breq->seg[seg].first_sect + 1;
+        nsects = breq->u.rw.seg[seg].last_sect - 
breq->u.rw.seg[seg].first_sect + 1;
         sector_nr += nsects;
     }
 
@@ -1366,7 +1366,7 @@
        req       = &vreq->req;
        id        = req->id;
        ring      = &vbd->ring;
-       sector_nr = req->sector_number;
+       sector_nr = req->u.rw.sector_number;
        image     = tapdisk_vbd_first_image(vbd);
 
        vreq->submitting = 1;
@@ -1385,10 +1385,10 @@
                goto fail;
 
        for (i = 0; i < req->nr_segments; i++) {
-               nsects = req->seg[i].last_sect - req->seg[i].first_sect + 1;
+               nsects = req->u.rw.seg[i].last_sect - 
req->u.rw.seg[i].first_sect + 1;
                page   = (char *)MMAP_VADDR(ring->vstart, 
                                           (unsigned long)req->id, i);
-               page  += (req->seg[i].first_sect << SECTOR_SHIFT);
+               page  += (req->u.rw.seg[i].first_sect << SECTOR_SHIFT);
 
                treq.id             = id;
                treq.sidx           = i;
@@ -1482,7 +1482,7 @@
                vreq->status = BLKIF_RSP_OKAY;
                DBG(TLOG_DBG, "retry #%d of req %"PRIu64", "
                    "sec 0x%08"PRIx64", nr_segs: %d\n", vreq->num_retries,
-                   vreq->req.id, vreq->req.sector_number,
+                   vreq->req.id, vreq->req.u.rw.sector_number,
                    vreq->req.nr_segments);
 
                err = tapdisk_vbd_issue_request(vbd, vreq);
diff -r 7b4c82f07281 -r 428420495fd3 xen/include/public/io/blkif.h
--- a/xen/include/public/io/blkif.h     Wed Jan 05 23:54:15 2011 +0000
+++ b/xen/include/public/io/blkif.h     Thu Jan 13 11:48:41 2011 +0000
@@ -103,7 +103,22 @@
     uint8_t     first_sect, last_sect;
 };
 
+struct blkif_request_rw {
+    blkif_sector_t sector_number;/* start sector idx on disk (r/w only)  */
+    struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
+};
+
 struct blkif_request {
+    uint8_t        operation;    /* BLKIF_OP_???                         */
+    uint8_t        nr_segments;  /* number of segments                   */
+    blkif_vdev_t   handle;       /* only for read/write requests         */
+    uint64_t       id;           /* private guest value, echoed in resp  */
+    union {
+        struct blkif_request_rw     rw;
+    } u;
+};
+
+struct blkif_request_old {
     uint8_t        operation;    /* BLKIF_OP_???                         */
     uint8_t        nr_segments;  /* number of segments                   */
     blkif_vdev_t   handle;       /* only for read/write requests         */

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel