[PATCH v6 01/15] vfio/type1: Refactor vfio_iommu_type1_ioctl()

Liu Yi L
2020-07-28T06:21:01Z

This patch refactors the vfio_iommu_type1_ioctl() to use switch instead of
if-else, and each command got a helper function.

Cc: Kevin Tian <kevin.tian@intel.com>
CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
---
v4 -> v5:
*) address comments from Eric Auger, add r-b from Eric.
---
drivers/vfio/vfio_iommu_type1.c | 394 ++++++++++++++++++++++------------------
1 file changed, 213 insertions(+), 181 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 5e556ac..3bd70ff 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -2453,6 +2453,23 @@ static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
return ret;
}

+static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
+ unsigned long arg)
+{
+ switch (arg) {
+ case VFIO_TYPE1_IOMMU:
+ case VFIO_TYPE1v2_IOMMU:
+ case VFIO_TYPE1_NESTING_IOMMU:
+ return 1;
+ case VFIO_DMA_CC_IOMMU:
+ if (!iommu)
+ return 0;
+ return vfio_domains_have_iommu_cache(iommu);
+ default:
+ return 0;
+ }
+}
+
static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
size_t size)
@@ -2529,241 +2546,256 @@ static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
}

-static long vfio_iommu_type1_ioctl(void *iommu_data,
- unsigned int cmd, unsigned long arg)
+static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
+ unsigned long arg)
{
- struct vfio_iommu *iommu = iommu_data;
+ struct vfio_iommu_type1_info info;
unsigned long minsz;
+ struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
+ unsigned long capsz;
+ int ret;

- if (cmd == VFIO_CHECK_EXTENSION) {
- switch (arg) {
- case VFIO_TYPE1_IOMMU:
- case VFIO_TYPE1v2_IOMMU:
- case VFIO_TYPE1_NESTING_IOMMU:
- return 1;
- case VFIO_DMA_CC_IOMMU:
- if (!iommu)
- return 0;
- return vfio_domains_have_iommu_cache(iommu);
- default:
- return 0;
- }
- } else if (cmd == VFIO_IOMMU_GET_INFO) {
- struct vfio_iommu_type1_info info;
- struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
- unsigned long capsz;
- int ret;
-
- minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
+ minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);

- /* For backward compatibility, cannot require this */
- capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
+ /* For backward compatibility, cannot require this */
+ capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);

- if (copy_from_user(&info, (void __user *)arg, minsz))
- return -EFAULT;
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;

- if (info.argsz < minsz)
- return -EINVAL;
+ if (info.argsz < minsz)
+ return -EINVAL;

- if (info.argsz >= capsz) {
- minsz = capsz;
- info.cap_offset = 0; /* output, no-recopy necessary */
- }
+ if (info.argsz >= capsz) {
+ minsz = capsz;
+ info.cap_offset = 0; /* output, no-recopy necessary */
+ }

- mutex_lock(&iommu->lock);
- info.flags = VFIO_IOMMU_INFO_PGSIZES;
+ mutex_lock(&iommu->lock);
+ info.flags = VFIO_IOMMU_INFO_PGSIZES;

- info.iova_pgsizes = iommu->pgsize_bitmap;
+ info.iova_pgsizes = iommu->pgsize_bitmap;

- ret = vfio_iommu_migration_build_caps(iommu, &caps);
+ ret = vfio_iommu_migration_build_caps(iommu, &caps);

- if (!ret)
- ret = vfio_iommu_iova_build_caps(iommu, &caps);
+ if (!ret)
+ ret = vfio_iommu_iova_build_caps(iommu, &caps);

- mutex_unlock(&iommu->lock);
+ mutex_unlock(&iommu->lock);

- if (ret)
- return ret;
+ if (ret)
+ return ret;

- if (caps.size) {
- info.flags |= VFIO_IOMMU_INFO_CAPS;
+ if (caps.size) {
+ info.flags |= VFIO_IOMMU_INFO_CAPS;

- if (info.argsz < sizeof(info) + caps.size) {
- info.argsz = sizeof(info) + caps.size;
- } else {
- vfio_info_cap_shift(&caps, sizeof(info));
- if (copy_to_user((void __user *)arg +
- sizeof(info), caps.buf,
- caps.size)) {
- kfree(caps.buf);
- return -EFAULT;
- }
- info.cap_offset = sizeof(info);
+ if (info.argsz < sizeof(info) + caps.size) {
+ info.argsz = sizeof(info) + caps.size;
+ } else {
+ vfio_info_cap_shift(&caps, sizeof(info));
+ if (copy_to_user((void __user *)arg +
+ sizeof(info), caps.buf,
+ caps.size)) {
+ kfree(caps.buf);
+ return -EFAULT;
}
-
- kfree(caps.buf);
+ info.cap_offset = sizeof(info);
}

- return copy_to_user((void __user *)arg, &info, minsz) ?
- -EFAULT : 0;
+ kfree(caps.buf);
+ }

- } else if (cmd == VFIO_IOMMU_MAP_DMA) {
- struct vfio_iommu_type1_dma_map map;
- uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
- VFIO_DMA_MAP_FLAG_WRITE;
+ return copy_to_user((void __user *)arg, &info, minsz) ?
+ -EFAULT : 0;
+}

- minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
+static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
+ unsigned long arg)
+{
+ struct vfio_iommu_type1_dma_map map;
+ unsigned long minsz;
+ uint32_t mask = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;

- if (copy_from_user(&map, (void __user *)arg, minsz))
- return -EFAULT;
+ minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);

- if (map.argsz < minsz || map.flags & ~mask)
- return -EINVAL;
+ if (copy_from_user(&map, (void __user *)arg, minsz))
+ return -EFAULT;

- return vfio_dma_do_map(iommu, &map);
+ if (map.argsz < minsz || map.flags & ~mask)
+ return -EINVAL;

- } else if (cmd == VFIO_IOMMU_UNMAP_DMA) {
- struct vfio_iommu_type1_dma_unmap unmap;
- struct vfio_bitmap bitmap = { 0 };
- int ret;
+ return vfio_dma_do_map(iommu, &map);
+}

- minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
+static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
+ unsigned long arg)
+{
+ struct vfio_iommu_type1_dma_unmap unmap;
+ struct vfio_bitmap bitmap = { 0 };
+ unsigned long minsz;
+ int ret;

- if (copy_from_user(&unmap, (void __user *)arg, minsz))
- return -EFAULT;
+ minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);

- if (unmap.argsz < minsz ||
- unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
- return -EINVAL;
+ if (copy_from_user(&unmap, (void __user *)arg, minsz))
+ return -EFAULT;

- if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
- unsigned long pgshift;
+ if (unmap.argsz < minsz ||
+ unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
+ return -EINVAL;

- if (unmap.argsz < (minsz + sizeof(bitmap)))
- return -EINVAL;
+ if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
+ unsigned long pgshift;

- if (copy_from_user(&bitmap,
- (void __user *)(arg + minsz),
- sizeof(bitmap)))
- return -EFAULT;
+ if (unmap.argsz < (minsz + sizeof(bitmap)))
+ return -EINVAL;

- if (!access_ok((void __user *)bitmap.data, bitmap.size))
- return -EINVAL;
+ if (copy_from_user(&bitmap,
+ (void __user *)(arg + minsz),
+ sizeof(bitmap)))
+ return -EFAULT;

- pgshift = __ffs(bitmap.pgsize);
- ret = verify_bitmap_size(unmap.size >> pgshift,
- bitmap.size);
- if (ret)
- return ret;
- }
+ if (!access_ok((void __user *)bitmap.data, bitmap.size))
+ return -EINVAL;

- ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
+ pgshift = __ffs(bitmap.pgsize);
+ ret = verify_bitmap_size(unmap.size >> pgshift,
+ bitmap.size);
if (ret)
return ret;
+ }
+
+ ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
+ if (ret)
+ return ret;

- return copy_to_user((void __user *)arg, &unmap, minsz) ?
+ return copy_to_user((void __user *)arg, &unmap, minsz) ?
-EFAULT : 0;
- } else if (cmd == VFIO_IOMMU_DIRTY_PAGES) {
- struct vfio_iommu_type1_dirty_bitmap dirty;
- uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
- VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
- VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
- int ret = 0;
+}

- if (!iommu->v2)
- return -EACCES;
+static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
+ unsigned long arg)
+{
+ struct vfio_iommu_type1_dirty_bitmap dirty;
+ uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
+ VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
+ VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
+ unsigned long minsz;
+ int ret = 0;

- minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
- flags);
+ if (!iommu->v2)
+ return -EACCES;

- if (copy_from_user(&dirty, (void __user *)arg, minsz))
- return -EFAULT;
+ minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap, flags);

- if (dirty.argsz < minsz || dirty.flags & ~mask)
- return -EINVAL;
+ if (copy_from_user(&dirty, (void __user *)arg, minsz))
+ return -EFAULT;

- /* only one flag should be set at a time */
- if (__ffs(dirty.flags) != __fls(dirty.flags))
- return -EINVAL;
+ if (dirty.argsz < minsz || dirty.flags & ~mask)
+ return -EINVAL;

- if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
- size_t pgsize;
+ /* only one flag should be set at a time */
+ if (__ffs(dirty.flags) != __fls(dirty.flags))
+ return -EINVAL;

- mutex_lock(&iommu->lock);
- pgsize = 1 << __ffs(iommu->pgsize_bitmap);
- if (!iommu->dirty_page_tracking) {
- ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
- if (!ret)
- iommu->dirty_page_tracking = true;
- }
- mutex_unlock(&iommu->lock);
- return ret;
- } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
- mutex_lock(&iommu->lock);
- if (iommu->dirty_page_tracking) {
- iommu->dirty_page_tracking = false;
- vfio_dma_bitmap_free_all(iommu);
- }
- mutex_unlock(&iommu->lock);
- return 0;
- } else if (dirty.flags &
- VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
- struct vfio_iommu_type1_dirty_bitmap_get range;
- unsigned long pgshift;
- size_t data_size = dirty.argsz - minsz;
- size_t iommu_pgsize;
-
- if (!data_size || data_size < sizeof(range))
- return -EINVAL;
-
- if (copy_from_user(&range, (void __user *)(arg + minsz),
- sizeof(range)))
- return -EFAULT;
+ if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
+ size_t pgsize;

- if (range.iova + range.size < range.iova)
- return -EINVAL;
- if (!access_ok((void __user *)range.bitmap.data,
- range.bitmap.size))
- return -EINVAL;
+ mutex_lock(&iommu->lock);
+ pgsize = 1 << __ffs(iommu->pgsize_bitmap);
+ if (!iommu->dirty_page_tracking) {
+ ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
+ if (!ret)
+ iommu->dirty_page_tracking = true;
+ }
+ mutex_unlock(&iommu->lock);
+ return ret;
+ } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
+ mutex_lock(&iommu->lock);
+ if (iommu->dirty_page_tracking) {
+ iommu->dirty_page_tracking = false;
+ vfio_dma_bitmap_free_all(iommu);
+ }
+ mutex_unlock(&iommu->lock);
+ return 0;
+ } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
+ struct vfio_iommu_type1_dirty_bitmap_get range;
+ unsigned long pgshift;
+ size_t data_size = dirty.argsz - minsz;
+ size_t iommu_pgsize;

- pgshift = __ffs(range.bitmap.pgsize);
- ret = verify_bitmap_size(range.size >> pgshift,
- range.bitmap.size);
- if (ret)
- return ret;
+ if (!data_size || data_size < sizeof(range))
+ return -EINVAL;

- mutex_lock(&iommu->lock);
+ if (copy_from_user(&range, (void __user *)(arg + minsz),
+ sizeof(range)))
+ return -EFAULT;

- iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
+ if (range.iova + range.size < range.iova)
+ return -EINVAL;
+ if (!access_ok((void __user *)range.bitmap.data,
+ range.bitmap.size))
+ return -EINVAL;

- /* allow only smallest supported pgsize */
- if (range.bitmap.pgsize != iommu_pgsize) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (range.iova & (iommu_pgsize - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (!range.size || range.size & (iommu_pgsize - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
+ pgshift = __ffs(range.bitmap.pgsize);
+ ret = verify_bitmap_size(range.size >> pgshift,
+ range.bitmap.size);
+ if (ret)
+ return ret;

- if (iommu->dirty_page_tracking)
- ret = vfio_iova_dirty_bitmap(range.bitmap.data,
- iommu, range.iova, range.size,
- range.bitmap.pgsize);
- else
- ret = -EINVAL;
-out_unlock:
- mutex_unlock(&iommu->lock);
+ mutex_lock(&iommu->lock);

- return ret;
+ iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
+
+ /* allow only smallest supported pgsize */
+ if (range.bitmap.pgsize != iommu_pgsize) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+ if (range.iova & (iommu_pgsize - 1)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+ if (!range.size || range.size & (iommu_pgsize - 1)) {
+ ret = -EINVAL;
+ goto out_unlock;
}
+
+ if (iommu->dirty_page_tracking)
+ ret = vfio_iova_dirty_bitmap(range.bitmap.data,
+ iommu, range.iova,
+ range.size,
+ range.bitmap.pgsize);
+ else
+ ret = -EINVAL;
+out_unlock:
+ mutex_unlock(&iommu->lock);
+
+ return ret;
}

- return -ENOTTY;
+ return -EINVAL;
+}
+
+static long vfio_iommu_type1_ioctl(void *iommu_data,
+ unsigned int cmd, unsigned long arg)
+{
+ struct vfio_iommu *iommu = iommu_data;
+
+ switch (cmd) {
+ case VFIO_CHECK_EXTENSION:
+ return vfio_iommu_type1_check_extension(iommu, arg);
+ case VFIO_IOMMU_GET_INFO:
+ return vfio_iommu_type1_get_info(iommu, arg);
+ case VFIO_IOMMU_MAP_DMA:
+ return vfio_iommu_type1_map_dma(iommu, arg);
+ case VFIO_IOMMU_UNMAP_DMA:
+ return vfio_iommu_type1_unmap_dma(iommu, arg);
+ case VFIO_IOMMU_DIRTY_PAGES:
+ return vfio_iommu_type1_dirty_pages(iommu, arg);
+ default:
+ return -ENOTTY;
+ }
}

static int vfio_iommu_type1_register_notifier(void *iommu_data,
--
2.7.4