Re: [PATCH 2/6] vhost: get guest/host physical address mappings
From: Maxime Coquelin <hidden>
Date: 2016-08-23 09:58:46
On 08/23/2016 10:10 AM, Yuanhan Liu wrote:
quoted hunk ↗ jump to hunk
So that we can convert a guest physical address to host physical address, which will be used in later Tx zero copy implementation. Signed-off-by: Yuanhan Liu <redacted> --- lib/librte_vhost/vhost.h | 30 +++++++++++++++ lib/librte_vhost/vhost_user.c | 86 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 116 insertions(+)diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index df2107b..2d52987 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h@@ -114,6 +114,12 @@ struct vhost_virtqueue { #define VIRTIO_F_VERSION_1 32 #endif +struct guest_page { + uint64_t guest_phys_addr; + uint64_t host_phys_addr; + uint64_t size; +}; + /** * Device structure contains all configuration information relating * to the device.@@ -137,6 +143,10 @@ struct virtio_net { uint64_t log_addr; struct ether_addr mac; + uint32_t nr_guest_pages; + uint32_t max_guest_pages; + struct guest_page *guest_pages; + } __rte_cache_aligned; /**@@ -217,6 +227,26 @@ gpa_to_vva(struct virtio_net *dev, uint64_t gpa) return 0; } +/* Convert guest physical address to host physical address */ +static inline phys_addr_t __attribute__((always_inline)) +gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size) +{ + uint32_t i; + struct guest_page *page; + + for (i = 0; i < dev->nr_guest_pages; i++) { + page = &dev->guest_pages[i]; + + if (gpa >= page->guest_phys_addr && + gpa + size < page->guest_phys_addr + page->size) {
Shouldn't be '<=' here?
quoted hunk ↗ jump to hunk
+ return gpa - page->guest_phys_addr + + page->host_phys_addr; + } + } + + return 0; +} + struct virtio_net_device_ops const *notify_ops; struct virtio_net *get_device(int vid);diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index d2071fd..045d4f0 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c@@ -372,6 +372,81 @@ vhost_user_set_vring_base(struct virtio_net *dev, return 0; } +static void +add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr, + uint64_t host_phys_addr, uint64_t size) +{ + struct guest_page *page; + + if (dev->nr_guest_pages == dev->max_guest_pages) { + dev->max_guest_pages *= 2; + dev->guest_pages = realloc(dev->guest_pages, + dev->max_guest_pages * sizeof(*page));
Maybe realloc return could be checked?
+ }
+
+ page = &dev->guest_pages[dev->nr_guest_pages++];
+ page->guest_phys_addr = guest_phys_addr;
+ page->host_phys_addr = host_phys_addr;
+ page->size = size;
+}
+
+static void
+add_guest_pages(struct virtio_net *dev, struct virtio_memory_region *reg,
+ uint64_t page_size)
+{
+ uint64_t reg_size = reg->size;
+ uint64_t host_user_addr = reg->host_user_addr;
+ uint64_t guest_phys_addr = reg->guest_phys_addr;
+ uint64_t host_phys_addr;
+ uint64_t size;
+ uint32_t pre_read;
+
+ pre_read = *((uint32_t *)(uintptr_t)host_user_addr);
+ host_phys_addr = rte_mem_virt2phy((void *)(uintptr_t)host_user_addr);
+ size = page_size - (guest_phys_addr & (page_size - 1));
+ size = RTE_MIN(size, reg_size);
+
+ add_one_guest_page(dev, guest_phys_addr, host_phys_addr, size);
+ host_user_addr += size;
+ guest_phys_addr += size;
+ reg_size -= size;
+
+ while (reg_size > 0) {
+ pre_read += *((uint32_t *)(uintptr_t)host_user_addr);
+ host_phys_addr = rte_mem_virt2phy((void *)(uintptr_t)host_user_addr);
+ add_one_guest_page(dev, guest_phys_addr, host_phys_addr, page_size);
+
+ host_user_addr += page_size;
+ guest_phys_addr += page_size;
+ reg_size -= page_size;
+ }
+
+ /* FIXME */
+ RTE_LOG(INFO, VHOST_CONFIG, ":: %u ::\n", pre_read);For my information, what is the purpose of pre_read?
quoted hunk ↗ jump to hunk
+} + +/* TODO: enable it only in debug mode? */ +static void +dump_guest_pages(struct virtio_net *dev) +{ + uint32_t i; + struct guest_page *page; + + for (i = 0; i < dev->nr_guest_pages; i++) { + page = &dev->guest_pages[i]; + + RTE_LOG(INFO, VHOST_CONFIG, + "guest physical page region %u\n" + "\t guest_phys_addr: %" PRIx64 "\n" + "\t host_phys_addr : %" PRIx64 "\n" + "\t size : %" PRIx64 "\n", + i, + page->guest_phys_addr, + page->host_phys_addr, + page->size); + } +} + static int vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg) {@@ -396,6 +471,13 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg) dev->mem = NULL; } + dev->nr_guest_pages = 0; + if (!dev->guest_pages) { + dev->max_guest_pages = 8; + dev->guest_pages = malloc(dev->max_guest_pages * + sizeof(struct guest_page)); + } + dev->mem = rte_zmalloc("vhost-mem-table", sizeof(struct virtio_memory) + sizeof(struct virtio_memory_region) * memory.nregions, 0); if (dev->mem == NULL) {@@ -447,6 +529,8 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg) reg->mmap_size = mmap_size; reg->host_user_addr = (uint64_t)(uintptr_t)mmap_addr + mmap_offset; + add_guest_pages(dev, reg, alignment); + RTE_LOG(INFO, VHOST_CONFIG, "guest memory region %u, size: 0x%" PRIx64 "\n" "\t guest physical addr: 0x%" PRIx64 "\n"@@ -466,6 +550,8 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg) mmap_offset); } + dump_guest_pages(dev); + return 0; err_mmap: