diff options
Diffstat (limited to 'linux/vm.c')
| -rw-r--r-- | linux/vm.c | 31 |
1 files changed, 17 insertions, 14 deletions
@@ -1,8 +1,7 @@ /* vm.c -- Memory mapping for DRM -*- linux-c -*- * Created: Mon Jan 4 08:58:31 1999 by faith@precisioninsight.com - * Revised: Mon Feb 14 00:16:45 2000 by kevin@precisioninsight.com * - * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. + * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a @@ -246,6 +245,18 @@ int drm_mmap(struct file *filp, struct vm_area_struct *vma) /* Check for valid size. */ if (map->size != vma->vm_end - vma->vm_start) return -EINVAL; + if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) { + vma->vm_flags &= VM_MAYWRITE; +#if defined(__i386__) + pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW; +#else + /* Ye gads this is ugly. With more thought + we could move this up higher and use + `protection_map' instead. */ + vma->vm_page_prot = __pgprot(pte_val(pte_wrprotect( + __pte(pgprot_val(vma->vm_page_prot))))); +#endif + } switch (map->type) { case _DRM_FRAME_BUFFER: @@ -265,6 +276,10 @@ int drm_mmap(struct file *filp, struct vm_area_struct *vma) vma->vm_end - vma->vm_start, vma->vm_page_prot)) return -EAGAIN; + DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx," + " offset = 0x%lx\n", + map->type, + vma->vm_start, vma->vm_end, VM_OFFSET(vma)); vma->vm_ops = &drm_vm_ops; break; case _DRM_SHM: @@ -277,19 +292,7 @@ int drm_mmap(struct file *filp, struct vm_area_struct *vma) return -EINVAL; /* This should never happen. */ } vma->vm_flags |= VM_LOCKED | VM_SHM; /* Don't swap */ - if (map->flags & _DRM_READ_ONLY) { -#if defined(__i386__) - pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW; -#else - /* Ye gads this is ugly. With more thought - we could move this up higher and use - `protection_map' instead. */ - vma->vm_page_prot = __pgprot(pte_val(pte_wrprotect( - __pte(pgprot_val(vma->vm_page_prot))))); -#endif - } - #if LINUX_VERSION_CODE < 0x020203 /* KERNEL_VERSION(2,2,3) */ /* In Linux 2.2.3 and above, this is handled in do_mmap() in mm/mmap.c. */ |