ide: move buffered DMA cancel to core
authorJohn Snow <jsnow@redhat.com>
Wed, 10 Feb 2016 18:29:39 +0000 (13:29 -0500)
committerJohn Snow <jsnow@redhat.com>
Wed, 10 Feb 2016 18:29:39 +0000 (13:29 -0500)
Buffered DMA cancellation was added to ATAPI devices and implemented
for the BMDMA HBA. Move the code over to common IDE code and allow
it to be used for any HBA.

Signed-off-by: John Snow <jsnow@redhat.com>
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1453225191-11871-4-git-send-email-jsnow@redhat.com

hw/ide/core.c
hw/ide/internal.h
hw/ide/pci.c

index 37d105841008b04a04f16340eb6022d4f944b35f..5cafcf5287604f6f44ba6a0a42689e4633998953 100644 (file)
@@ -609,6 +609,51 @@ BlockAIOCB *ide_buffered_readv(IDEState *s, int64_t sector_num,
     return aioreq;
 }
 
+/**
+ * Cancel all pending DMA requests.
+ * Any buffered DMA requests are instantly canceled,
+ * but any pending unbuffered DMA requests must be waited on.
+ */
+void ide_cancel_dma_sync(IDEState *s)
+{
+    IDEBufferedRequest *req;
+
+    /* First invoke the callbacks of all buffered requests
+     * and flag those requests as orphaned. Ideally there
+     * are no unbuffered (Scatter Gather DMA Requests or
+     * write requests) pending and we can avoid to drain. */
+    QLIST_FOREACH(req, &s->buffered_requests, list) {
+        if (!req->orphaned) {
+#ifdef DEBUG_IDE
+            printf("%s: invoking cb %p of buffered request %p with"
+                   " -ECANCELED\n", __func__, req->original_cb, req);
+#endif
+            req->original_cb(req->original_opaque, -ECANCELED);
+        }
+        req->orphaned = true;
+    }
+
+    /*
+     * We can't cancel Scatter Gather DMA in the middle of the
+     * operation or a partial (not full) DMA transfer would reach
+     * the storage so we wait for completion instead (we beahve
+     * like if the DMA was completed by the time the guest trying
+     * to cancel dma with bmdma_cmd_writeb with BM_CMD_START not
+     * set).
+     *
+     * In the future we'll be able to safely cancel the I/O if the
+     * whole DMA operation will be submitted to disk with a single
+     * aio operation with preadv/pwritev.
+     */
+    if (s->bus->dma->aiocb) {
+#ifdef DEBUG_IDE
+        printf("%s: draining all remaining requests", __func__);
+#endif
+        blk_drain_all();
+        assert(s->bus->dma->aiocb == NULL);
+    }
+}
+
 static void ide_sector_read(IDEState *s);
 
 static void ide_sector_read_cb(void *opaque, int ret)
index 2d1e2d2d2fa856afd6f42c70bc0e6bcf168e1e97..86bde26551840887454ab362762b480859bfbd01 100644 (file)
@@ -586,6 +586,7 @@ BlockAIOCB *ide_issue_trim(BlockBackend *blk,
 BlockAIOCB *ide_buffered_readv(IDEState *s, int64_t sector_num,
                                QEMUIOVector *iov, int nb_sectors,
                                BlockCompletionFunc *cb, void *opaque);
+void ide_cancel_dma_sync(IDEState *s);
 
 /* hw/ide/atapi.c */
 void ide_atapi_cmd(IDEState *s);
index fa5b63bc3f94153ed36638b0228639659626cb1c..92ffee7264345e8aa8f3511bdfe5011938e0731b 100644 (file)
@@ -234,41 +234,7 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val)
     /* Ignore writes to SSBM if it keeps the old value */
     if ((val & BM_CMD_START) != (bm->cmd & BM_CMD_START)) {
         if (!(val & BM_CMD_START)) {
-            /* First invoke the callbacks of all buffered requests
-             * and flag those requests as orphaned. Ideally there
-             * are no unbuffered (Scatter Gather DMA Requests or
-             * write requests) pending and we can avoid to drain. */
-            IDEBufferedRequest *req;
-            IDEState *s = idebus_active_if(bm->bus);
-            QLIST_FOREACH(req, &s->buffered_requests, list) {
-                if (!req->orphaned) {
-#ifdef DEBUG_IDE
-                    printf("%s: invoking cb %p of buffered request %p with"
-                           " -ECANCELED\n", __func__, req->original_cb, req);
-#endif
-                    req->original_cb(req->original_opaque, -ECANCELED);
-                }
-                req->orphaned = true;
-            }
-            /*
-             * We can't cancel Scatter Gather DMA in the middle of the
-             * operation or a partial (not full) DMA transfer would reach
-             * the storage so we wait for completion instead (we beahve
-             * like if the DMA was completed by the time the guest trying
-             * to cancel dma with bmdma_cmd_writeb with BM_CMD_START not
-             * set).
-             *
-             * In the future we'll be able to safely cancel the I/O if the
-             * whole DMA operation will be submitted to disk with a single
-             * aio operation with preadv/pwritev.
-             */
-            if (bm->bus->dma->aiocb) {
-#ifdef DEBUG_IDE
-                printf("%s: draining all remaining requests", __func__);
-#endif
-                blk_drain_all();
-                assert(bm->bus->dma->aiocb == NULL);
-            }
+            ide_cancel_dma_sync(idebus_active_if(bm->bus));
             bm->status &= ~BM_STATUS_DMAING;
         } else {
             bm->cur_addr = bm->addr;