diff options
Diffstat (limited to 'hw/virtio/dataplane/vring.c')
| -rw-r--r-- | hw/virtio/dataplane/vring.c | 78 |
1 files changed, 70 insertions, 8 deletions
diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c index 1bf9dd335a..250d45ec3d 100644 --- a/hw/virtio/dataplane/vring.c +++ b/hw/virtio/dataplane/vring.c @@ -15,9 +15,53 @@ */ #include "trace.h" +#include "hw/hw.h" +#include "exec/memory.h" +#include "exec/address-spaces.h" #include "hw/virtio/dataplane/vring.h" #include "qemu/error-report.h" +/* vring_map can be coupled with vring_unmap or (if you still have the + * value returned in *mr) memory_region_unref. + */ +static void *vring_map(MemoryRegion **mr, hwaddr phys, hwaddr len, + bool is_write) +{ + MemoryRegionSection section = memory_region_find(get_system_memory(), phys, len); + + if (!section.mr || int128_get64(section.size) < len) { + goto out; + } + if (is_write && section.readonly) { + goto out; + } + if (!memory_region_is_ram(section.mr)) { + goto out; + } + + /* Ignore regions with dirty logging, we cannot mark them dirty */ + if (memory_region_is_logging(section.mr)) { + goto out; + } + + *mr = section.mr; + return memory_region_get_ram_ptr(section.mr) + section.offset_within_region; + +out: + memory_region_unref(section.mr); + *mr = NULL; + return NULL; +} + +static void vring_unmap(void *buffer, bool is_write) +{ + ram_addr_t addr; + MemoryRegion *mr; + + mr = qemu_ram_addr_from_host(buffer, &addr); + memory_region_unref(mr); +} + /* Map the guest's vring to host memory */ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n) { @@ -27,8 +71,7 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n) vring->broken = false; - hostmem_init(&vring->hostmem); - vring_ptr = hostmem_lookup(&vring->hostmem, vring_addr, vring_size, true); + vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true); if (!vring_ptr) { error_report("Failed to map vring " "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, @@ -54,7 +97,7 @@ void vring_teardown(Vring *vring, VirtIODevice *vdev, int n) virtio_queue_set_last_avail_idx(vdev, n, vring->last_avail_idx); virtio_queue_invalidate_signalled_used(vdev, n); - hostmem_finalize(&vring->hostmem); + memory_region_unref(vring->mr); } /* Disable guest->host notifies */ @@ -117,6 +160,7 @@ static int get_desc(Vring *vring, VirtQueueElement *elem, unsigned *num; struct iovec *iov; hwaddr *addr; + MemoryRegion *mr; if (desc->flags & VRING_DESC_F_WRITE) { num = &elem->in_num; @@ -141,14 +185,16 @@ static int get_desc(Vring *vring, VirtQueueElement *elem, } /* TODO handle non-contiguous memory across region boundaries */ - iov->iov_base = hostmem_lookup(&vring->hostmem, desc->addr, desc->len, - desc->flags & VRING_DESC_F_WRITE); + iov->iov_base = vring_map(&mr, desc->addr, desc->len, + desc->flags & VRING_DESC_F_WRITE); if (!iov->iov_base) { error_report("Failed to map descriptor addr %#" PRIx64 " len %u", (uint64_t)desc->addr, desc->len); return -EFAULT; } + /* The MemoryRegion is looked up again and unref'ed later, leave the + * ref in place. */ iov->iov_len = desc->len; *addr = desc->addr; *num += 1; @@ -183,11 +229,12 @@ static int get_indirect(Vring *vring, VirtQueueElement *elem, do { struct vring_desc *desc_ptr; + MemoryRegion *mr; /* Translate indirect descriptor */ - desc_ptr = hostmem_lookup(&vring->hostmem, - indirect->addr + found * sizeof(desc), - sizeof(desc), false); + desc_ptr = vring_map(&mr, + indirect->addr + found * sizeof(desc), + sizeof(desc), false); if (!desc_ptr) { error_report("Failed to map indirect descriptor " "addr %#" PRIx64 " len %zu", @@ -197,6 +244,7 @@ static int get_indirect(Vring *vring, VirtQueueElement *elem, return -EFAULT; } desc = *desc_ptr; + memory_region_unref(mr); /* Ensure descriptor has been loaded before accessing fields */ barrier(); /* read_barrier_depends(); */ @@ -226,6 +274,20 @@ static int get_indirect(Vring *vring, VirtQueueElement *elem, void vring_free_element(VirtQueueElement *elem) { + int i; + + /* This assumes that the iovecs, if changed, are never moved past + * the end of the valid area. This is true if iovec manipulations + * are done with iov_discard_front and iov_discard_back. + */ + for (i = 0; i < elem->out_num; i++) { + vring_unmap(elem->out_sg[i].iov_base, false); + } + + for (i = 0; i < elem->in_num; i++) { + vring_unmap(elem->in_sg[i].iov_base, true); + } + g_slice_free(VirtQueueElement, elem); } |