diff options
| author | Julien Grall <julien.grall@citrix.com> | 2015-05-05 18:54:12 +0300 |
|---|---|---|
| committer | David Vrabel <david.vrabel@citrix.com> | 2015-10-23 16:20:42 +0300 |
| commit | 5995a68a6272e4e8f4fe4de82cdc877e650fe8be (patch) | |
| tree | 2699b77a0e00a61dfb0a1d3eb65b4645a67274a8 /drivers/xen/privcmd.c | |
| parent | d0089e8a0e4c9723d85b01713671358e3d6960df (diff) | |
| download | linux-5995a68a6272e4e8f4fe4de82cdc877e650fe8be.tar.xz | |
xen/privcmd: Add support for Linux 64KB page granularity
The hypercall interface (as well as the toolstack) is always using 4KB
page granularity. When the toolstack is asking for mapping a series of
guest PFN in a batch, it expects to have the page map contiguously in
its virtual memory.
When Linux is using 64KB page granularity, the privcmd driver will have
to map multiple Xen PFN in a single Linux page.
Note that this solution works on page granularity which is a multiple of
4KB.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Diffstat (limited to 'drivers/xen/privcmd.c')
| -rw-r--r-- | drivers/xen/privcmd.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index b199ad3d4587..df2e6f783318 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -446,7 +446,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version) return -EINVAL; } - nr_pages = m.num; + nr_pages = DIV_ROUND_UP(m.num, XEN_PFN_PER_PAGE); if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT))) return -EINVAL; @@ -494,7 +494,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version) goto out_unlock; } if (xen_feature(XENFEAT_auto_translated_physmap)) { - ret = alloc_empty_pages(vma, m.num); + ret = alloc_empty_pages(vma, nr_pages); if (ret < 0) goto out_unlock; } else @@ -518,6 +518,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version) state.global_error = 0; state.version = version; + BUILD_BUG_ON(((PAGE_SIZE / sizeof(xen_pfn_t)) % XEN_PFN_PER_PAGE) != 0); /* mmap_batch_fn guarantees ret == 0 */ BUG_ON(traverse_pages_block(m.num, sizeof(xen_pfn_t), &pagelist, mmap_batch_fn, &state)); @@ -582,12 +583,13 @@ static void privcmd_close(struct vm_area_struct *vma) { struct page **pages = vma->vm_private_data; int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; + int numgfns = (vma->vm_end - vma->vm_start) >> XEN_PAGE_SHIFT; int rc; if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages) return; - rc = xen_unmap_domain_gfn_range(vma, numpgs, pages); + rc = xen_unmap_domain_gfn_range(vma, numgfns, pages); if (rc == 0) free_xenballooned_pages(numpgs, pages); else |