From e16e12be34648777606a2c03a3526409b38f0e63 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 7 Oct 2014 16:39:42 +0200 Subject: virtio: use u32, not bitmap for features It seemed like a good idea to use bitmap for features in struct virtio_device, but it's actually a pain, and seems to become even more painful when we get more than 32 feature bits. Just change it to a u32 for now. Based on patch by Rusty. Suggested-by: David Hildenbrand Signed-off-by: Rusty Russell Signed-off-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck --- tools/virtio/linux/virtio.h | 22 +--------------------- tools/virtio/linux/virtio_config.h | 2 +- tools/virtio/virtio_test.c | 5 ++--- tools/virtio/vringh_test.c | 16 ++++++++-------- 4 files changed, 12 insertions(+), 33 deletions(-) (limited to 'tools/virtio') diff --git a/tools/virtio/linux/virtio.h b/tools/virtio/linux/virtio.h index 5a2d1f0f6bc7..72bff70bfeeb 100644 --- a/tools/virtio/linux/virtio.h +++ b/tools/virtio/linux/virtio.h @@ -6,31 +6,11 @@ /* TODO: empty stubs for now. Broken but enough for virtio_ring.c */ #define list_add_tail(a, b) do {} while (0) #define list_del(a) do {} while (0) - -#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) -#define BITS_PER_BYTE 8 -#define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE) -#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) - -/* TODO: Not atomic as it should be: - * we don't use this for anything important. */ -static inline void clear_bit(int nr, volatile unsigned long *addr) -{ - unsigned long mask = BIT_MASK(nr); - unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); - - *p &= ~mask; -} - -static inline int test_bit(int nr, const volatile unsigned long *addr) -{ - return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); -} /* end of stubs */ struct virtio_device { void *dev; - unsigned long features[1]; + u32 features; }; struct virtqueue { diff --git a/tools/virtio/linux/virtio_config.h b/tools/virtio/linux/virtio_config.h index 5049967f99f7..83b27e8e9d72 100644 --- a/tools/virtio/linux/virtio_config.h +++ b/tools/virtio/linux/virtio_config.h @@ -2,5 +2,5 @@ #define VIRTIO_TRANSPORT_F_END 32 #define virtio_has_feature(dev, feature) \ - test_bit((feature), (dev)->features) + (__virtio_test_bit((dev), feature)) diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c index 00ea679b3826..db3437c641a6 100644 --- a/tools/virtio/virtio_test.c +++ b/tools/virtio/virtio_test.c @@ -60,7 +60,7 @@ void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info) { struct vhost_vring_state state = { .index = info->idx }; struct vhost_vring_file file = { .index = info->idx }; - unsigned long long features = dev->vdev.features[0]; + unsigned long long features = dev->vdev.features; struct vhost_vring_addr addr = { .index = info->idx, .desc_user_addr = (uint64_t)(unsigned long)info->vring.desc, @@ -113,8 +113,7 @@ static void vdev_info_init(struct vdev_info* dev, unsigned long long features) { int r; memset(dev, 0, sizeof *dev); - dev->vdev.features[0] = features; - dev->vdev.features[1] = features >> 32; + dev->vdev.features = features; dev->buf_size = 1024; dev->buf = malloc(dev->buf_size); assert(dev->buf); diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c index 14a4f4cab5b9..9d4b1bca54be 100644 --- a/tools/virtio/vringh_test.c +++ b/tools/virtio/vringh_test.c @@ -304,7 +304,7 @@ static int parallel_test(unsigned long features, close(to_guest[1]); close(to_host[0]); - gvdev.vdev.features[0] = features; + gvdev.vdev.features = features; gvdev.to_host_fd = to_host[1]; gvdev.notifies = 0; @@ -449,13 +449,13 @@ int main(int argc, char *argv[]) bool fast_vringh = false, parallel = false; getrange = getrange_iov; - vdev.features[0] = 0; + vdev.features = 0; while (argv[1]) { if (strcmp(argv[1], "--indirect") == 0) - vdev.features[0] |= (1 << VIRTIO_RING_F_INDIRECT_DESC); + __virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); else if (strcmp(argv[1], "--eventidx") == 0) - vdev.features[0] |= (1 << VIRTIO_RING_F_EVENT_IDX); + __virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX); else if (strcmp(argv[1], "--slow-range") == 0) getrange = getrange_slow; else if (strcmp(argv[1], "--fast-vringh") == 0) @@ -468,7 +468,7 @@ int main(int argc, char *argv[]) } if (parallel) - return parallel_test(vdev.features[0], getrange, fast_vringh); + return parallel_test(vdev.features, getrange, fast_vringh); if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0) abort(); @@ -483,7 +483,7 @@ int main(int argc, char *argv[]) /* Set up host side. */ vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN); - vringh_init_user(&vrh, vdev.features[0], RINGSIZE, true, + vringh_init_user(&vrh, vdev.features, RINGSIZE, true, vrh.vring.desc, vrh.vring.avail, vrh.vring.used); /* No descriptor to get yet... */ @@ -652,13 +652,13 @@ int main(int argc, char *argv[]) } /* Test weird (but legal!) indirect. */ - if (vdev.features[0] & (1 << VIRTIO_RING_F_INDIRECT_DESC)) { + if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) { char *data = __user_addr_max - USER_MEM/4; struct vring_desc *d = __user_addr_max - USER_MEM/2; struct vring vring; /* Force creation of direct, which we modify. */ - vdev.features[0] &= ~(1 << VIRTIO_RING_F_INDIRECT_DESC); + __virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, __user_addr_min, never_notify_host, -- cgit v1.2.3-59-g8ed1b