RE: [PATCH V3 28/42] backends/iommufd: iommufd_backend_map_file_dma

[Duan, Zhenzhong]

>-----Original Message-----
>From: Steve Sistare <steven.sistare@oracle.com>
>Subject: [PATCH V3 28/42] backends/iommufd:
>iommufd_backend_map_file_dma
>
>Define iommufd_backend_map_file_dma to implement IOMMU_IOAS_MAP_FILE.
>This will be called as a substitute for iommufd_backend_map_dma, so
>the error conditions for BARs are copied as-is from that function.
>
>Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>---
> backends/iommufd.c       | 36 ++++++++++++++++++++++++++++++++++++
> backends/trace-events    |  1 +
> include/system/iommufd.h |  3 +++
> 3 files changed, 40 insertions(+)
>
>diff --git a/backends/iommufd.c b/backends/iommufd.c
>index b73f75c..5c1958f 100644
>--- a/backends/iommufd.c
>+++ b/backends/iommufd.c
>@@ -172,6 +172,42 @@ int iommufd_backend_map_dma(IOMMUFDBackend
>*be, uint32_t ioas_id, hwaddr iova,
>     return ret;
> }
>
>+int iommufd_backend_map_file_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>+                                 hwaddr iova, ram_addr_t size,
>+                                 int mfd, unsigned long start, bool readonly)
>+{
>+    int ret, fd = be->fd;
>+    struct iommu_ioas_map_file map = {
>+        .size = sizeof(map),
>+        .flags = IOMMU_IOAS_MAP_READABLE |
>+                 IOMMU_IOAS_MAP_FIXED_IOVA,
>+        .ioas_id = ioas_id,
>+        .fd = mfd,
>+        .start = start,
>+        .iova = iova,
>+        .length = size,
>+    };
>+
>+    if (!readonly) {
>+        map.flags |= IOMMU_IOAS_MAP_WRITEABLE;
>+    }
>+
>+    ret = ioctl(fd, IOMMU_IOAS_MAP_FILE, &map);
>+    trace_iommufd_backend_map_file_dma(fd, ioas_id, iova, size, mfd, start,
>+                                       readonly, ret);
>+    if (ret) {
>+        ret = -errno;
>+
>+        /* TODO: Not support mapping hardware PCI BAR region for now. */
>+        if (errno == EFAULT) {
>+            warn_report("IOMMU_IOAS_MAP_FILE failed: %m, PCI BAR?");
>+        } else {
>+            error_report("IOMMU_IOAS_MAP_FILE failed: %m");

No need to print error here as caller does the same thing.

>+        }
>+    }
>+    return ret;
>+}
>+
> int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>                               hwaddr iova, ram_addr_t size)
> {
>diff --git a/backends/trace-events b/backends/trace-events
>index 40811a3..f478e18 100644
>--- a/backends/trace-events
>+++ b/backends/trace-events
>@@ -11,6 +11,7 @@ iommufd_backend_connect(int fd, bool owned, uint32_t
>users) "fd=%d owned=%d user
> iommufd_backend_disconnect(int fd, uint32_t users) "fd=%d users=%d"
> iommu_backend_set_fd(int fd) "pre-opened /dev/iommu fd=%d"
> iommufd_backend_map_dma(int iommufd, uint32_t ioas, uint64_t iova, uint64_t
>size, void *vaddr, bool readonly, int ret) " iommufd=%d ioas=%d
>iova=0x%"PRIx64" size=0x%"PRIx64" addr=%p readonly=%d (%d)"
>+iommufd_backend_map_file_dma(int iommufd, uint32_t ioas, uint64_t iova,
>uint64_t size, int fd, unsigned long start, bool readonly, int ret) " 
>iommufd=%d
>ioas=%d iova=0x%"PRIx64" size=0x%"PRIx64" fd=%d start=%ld readonly=%d
>(%d)"
> iommufd_backend_unmap_dma_non_exist(int iommufd, uint32_t ioas, uint64_t
>iova, uint64_t size, int ret) " Unmap nonexistent mapping: iommufd=%d ioas=%d
>iova=0x%"PRIx64" size=0x%"PRIx64" (%d)"
> iommufd_backend_unmap_dma(int iommufd, uint32_t ioas, uint64_t iova,
>uint64_t size, int ret) " iommufd=%d ioas=%d iova=0x%"PRIx64"
>size=0x%"PRIx64" (%d)"
> iommufd_backend_alloc_ioas(int iommufd, uint32_t ioas) " iommufd=%d
>ioas=%d"
>diff --git a/include/system/iommufd.h b/include/system/iommufd.h
>index cbab75b..ac700b8 100644
>--- a/include/system/iommufd.h
>+++ b/include/system/iommufd.h
>@@ -43,6 +43,9 @@ void iommufd_backend_disconnect(IOMMUFDBackend
>*be);
> bool iommufd_backend_alloc_ioas(IOMMUFDBackend *be, uint32_t *ioas_id,
>                                 Error **errp);
> void iommufd_backend_free_id(IOMMUFDBackend *be, uint32_t id);
>+int iommufd_backend_map_file_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>+                                 hwaddr iova, ram_addr_t size, int fd,
>+                                 unsigned long start, bool readonly);
> int iommufd_backend_map_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>hwaddr iova,
>                             ram_addr_t size, void *vaddr, bool readonly);
> int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>--
>1.8.3.1