IB/ipath: drop requirement that PIO buffers be mmaped write-only

Some userlands try to mmap these pages read-write, so accommodate them.

Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 4 insertions, 9 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index 0b6e7679eefd..e999a46bef9b 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -992,15 +992,10 @@ static int mmap_piobufs(struct vm_area_struct *vma,
         pgprot_val(vma->vm_page_prot) &= ~_PAGE_GUARDED;
 #endif
 
-        if (vma->vm_flags & VM_READ) {
-                dev_info(&dd->pcidev->dev,
-                         "Can't map piobufs as readable (flags=%lx)\n",
-                         vma->vm_flags);
-                ret = -EPERM;
-                goto bail;
-        }
-
-        /* don't allow them to later change to readable with mprotect */
+        /*
+         * don't allow them to later change to readable with mprotect (for when
+         * not initially mapped readable, as is normally the case)
+         */
         vma->vm_flags &= ~VM_MAYREAD;
         vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;