diff options
| author | Joao Martins <joao.m.martins@oracle.com> | 2024-02-02 13:34:15 +0000 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2024-02-06 11:31:46 -0400 |
| commit | 4bbcbc6ea2fa379632a24c14cfb47aa603816ac6 (patch) | |
| tree | 5b3c81d63f323e4e6fa40831acf52b95998f5fc3 /drivers/iommu | |
| parent | fe13166f0562117c42fc60a109e664a914523e63 (diff) | |
| download | linux-4bbcbc6ea2fa379632a24c14cfb47aa603816ac6.tar.gz | |
iommufd/iova_bitmap: Consider page offset for the pages to be pinned
For small bitmaps that aren't PAGE_SIZE aligned *and* that are less than
512 pages in bitmap length, use an extra page to be able to cover the
entire range e.g. [1M..3G] which would be iterated more efficiently in a
single iteration, rather than two.
Fixes: b058ea3ab5af ("vfio/iova_bitmap: refactor iova_bitmap_set() to better handle page boundaries")
Link: https://lore.kernel.org/r/20240202133415.23819-10-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/iommufd/iova_bitmap.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/iommu/iommufd/iova_bitmap.c b/drivers/iommu/iommufd/iova_bitmap.c index b370e8ee886654..db8c46bee1559a 100644 --- a/drivers/iommu/iommufd/iova_bitmap.c +++ b/drivers/iommu/iommufd/iova_bitmap.c @@ -179,17 +179,18 @@ static int iova_bitmap_get(struct iova_bitmap *bitmap) sizeof(*bitmap->bitmap), PAGE_SIZE); /* - * We always cap at max number of 'struct page' a base page can fit. - * This is, for example, on x86 means 2M of bitmap data max. - */ - npages = min(npages, PAGE_SIZE / sizeof(struct page *)); - - /* * Bitmap address to be pinned is calculated via pointer arithmetic * with bitmap u64 word index. */ addr = bitmap->bitmap + bitmap->mapped_base_index; + /* + * We always cap at max number of 'struct page' a base page can fit. + * This is, for example, on x86 means 2M of bitmap data max. + */ + npages = min(npages + !!offset_in_page(addr), + PAGE_SIZE / sizeof(struct page *)); + ret = pin_user_pages_fast((unsigned long)addr, npages, FOLL_WRITE, mapped->pages); if (ret <= 0) |