Added APIs for pining and unpining set of pages. These call back into
backend iommu module to actually pin and unpin pages.
Added two new callback functions to struct vfio_iommu_driver_ops. Backend
IOMMU module that supports pining and unpinning pages for mdev devices
should provide these functions.
Renamed static functions in vfio_type1_iommu.c to resolve conflicts
Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com>
Signed-off-by: Neo Jia <c...@nvidia.com>
Reviewed-by: Dong Jia Shi <bjsdj...@linux.vnet.ibm.com>
Change-Id: Ia7417723aaae86bec2959ad9ae6c2915ddd340e0
---
drivers/vfio/vfio.c | 102 ++++++++++++++++++++++++++++++++++++++++
drivers/vfio/vfio_iommu_type1.c | 20 ++++----
include/linux/vfio.h | 13 ++++-
3 files changed, 124 insertions(+), 11 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 2e83bdf007fe..bd36c16b0ef2 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1799,6 +1799,108 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps,
size_t offset)
}
EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+
+/*
+ * Pin a set of guest PFNs and return their associated host PFNs for local
+ * domain only.
+ * @dev [in] : device
+ * @user_pfn [in]: array of user/guest PFNs to be unpinned.
+ * @npage [in] : count of elements in user_pfn array. This count should not
+ * be greater VFIO_PIN_PAGES_MAX_ENTRIES.
+ * @prot [in] : protection flags
+ * @phys_pfn[out]: array of host PFNs
+ * Return error or number of pages pinned.
+ */
+int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
+ int prot, unsigned long *phys_pfn)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ int ret;
+
+ if (!dev || !user_pfn || !phys_pfn || !npage)
+ return -EINVAL;
+
+ if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
+ return -E2BIG;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_pin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->pin_pages))
+ ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
+ npage, prot, phys_pfn);
+ else
+ ret = -ENOTTY;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_pin_pages:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_pin_pages);
+
+/*
+ * Unpin set of host PFNs for local domain only.
+ * @dev [in] : device
+ * @user_pfn [in]: array of user/guest PFNs to be unpinned. Number of
user/guest
+ * PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
+ * @npage [in] : count of elements in user_pfn array. This count should not
+ * be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
+ * Return error or number of pages unpinned.
+ */
+int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ int ret;
+
+ if (!dev || !user_pfn || !npage)
+ return -EINVAL;
+
+ if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
+ return -E2BIG;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_unpin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->unpin_pages))
+ ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
+ npage);
+ else
+ ret = -ENOTTY;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_unpin_pages:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_unpin_pages);
+
/**
* Module/class support
*/
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 2ba19424e4a1..9f3d58d3dfaf 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -259,8 +259,8 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot,
unsigned long *pfn)
* the iommu can only map chunks of consecutive pfns anyway, so get the
* first page and all consecutive pages with the same locking.
*/
-static long vfio_pin_pages(unsigned long vaddr, long npage,
- int prot, unsigned long *pfn_base)
+static long vfio_pin_pages_remote(unsigned long vaddr, long npage,
+ int prot, unsigned long *pfn_base)
{
unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
bool lock_cap = capable(CAP_IPC_LOCK);
@@ -318,8 +318,8 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
return i;
}
-static long vfio_unpin_pages(unsigned long pfn, long npage,
- int prot, bool do_accounting)
+static long vfio_unpin_pages_remote(unsigned long pfn, long npage,
+ int prot, bool do_accounting)
{
unsigned long unlocked = 0;
long i;
@@ -382,9 +382,9 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu,
struct vfio_dma *dma)
if (WARN_ON(!unmapped))
break;
- unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
- unmapped >> PAGE_SHIFT,
- dma->prot, false);
+ unlocked += vfio_unpin_pages_remote(phys >> PAGE_SHIFT,
+ unmapped >> PAGE_SHIFT,
+ dma->prot, false);
iova += unmapped;
cond_resched();
@@ -613,8 +613,8 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
while (size) {
/* Pin a contiguous chunk of memory */
- npage = vfio_pin_pages(vaddr + dma->size,
- size >> PAGE_SHIFT, prot, &pfn);
+ npage = vfio_pin_pages_remote(vaddr + dma->size,
+ size >> PAGE_SHIFT, prot, &pfn);
if (npage <= 0) {
WARN_ON(!npage);
ret = (int)npage;
@@ -624,7 +624,7 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
/* Map it! */
ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
if (ret) {
- vfio_unpin_pages(pfn, npage, prot, true);
+ vfio_unpin_pages_remote(pfn, npage, prot, true);
break;
}
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 0ecae0b1cd34..3c862a030029 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -75,7 +75,11 @@ struct vfio_iommu_driver_ops {
struct iommu_group *group);
void (*detach_group)(void *iommu_data,
struct iommu_group *group);
-
+ int (*pin_pages)(void *iommu_data, unsigned long *user_pfn,
+ int npage, int prot,
+ unsigned long *phys_pfn);
+ int (*unpin_pages)(void *iommu_data,
+ unsigned long *user_pfn, int npage);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -92,6 +96,13 @@ extern int vfio_external_user_iommu_id(struct vfio_group
*group);
extern long vfio_external_check_extension(struct vfio_group *group,
unsigned long arg);
+#define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long))
+
+extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ int npage, int prot, unsigned long *phys_pfn);
+extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+ int npage);
+
/*
* Sub-module helpers
*/
--
2.7.0
