From 6be5ceb02e98eaf6cfc4f8b12a896d04023f340d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 20 Apr 2012 17:13:58 -0700 Subject: VM: add "vm_mmap()" helper function This continues the theme started with vm_brk() and vm_munmap(): vm_mmap() does the same thing as do_mmap(), but additionally does the required VM locking. This uninlines (and rewrites it to be clearer) do_mmap(), which sadly duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have to export our internal do_mmap_pgoff() function. Some day we hopefully don't have to export do_mmap() either, if all modular users can become the simpler vm_mmap() instead. We're actually very close to that already, with the notable exception of the (broken) use in i810, and a couple of stragglers in binfmt_elf. Signed-off-by: Linus Torvalds --- drivers/gpu/drm/drm_bufs.c | 12 ++++-------- drivers/gpu/drm/exynos/exynos_drm_gem.c | 4 +--- drivers/gpu/drm/i810/i810_dma.c | 1 + drivers/gpu/drm/i915/i915_gem.c | 4 +--- 4 files changed, 7 insertions(+), 14 deletions(-) (limited to 'drivers/gpu') diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c index 30372f7..348b367 100644 --- a/drivers/gpu/drm/drm_bufs.c +++ b/drivers/gpu/drm/drm_bufs.c @@ -1510,8 +1510,8 @@ int drm_freebufs(struct drm_device *dev, void *data, * \param arg pointer to a drm_buf_map structure. * \return zero on success or a negative number on failure. * - * Maps the AGP, SG or PCI buffer region with do_mmap(), and copies information - * about each buffer into user space. For PCI buffers, it calls do_mmap() with + * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information + * about each buffer into user space. For PCI buffers, it calls vm_mmap() with * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls * drm_mmap_dma(). */ @@ -1553,18 +1553,14 @@ int drm_mapbufs(struct drm_device *dev, void *data, retcode = -EINVAL; goto done; } - down_write(¤t->mm->mmap_sem); - virtual = do_mmap(file_priv->filp, 0, map->size, + virtual = vm_mmap(file_priv->filp, 0, map->size, PROT_READ | PROT_WRITE, MAP_SHARED, token); - up_write(¤t->mm->mmap_sem); } else { - down_write(¤t->mm->mmap_sem); - virtual = do_mmap(file_priv->filp, 0, dma->byte_count, + virtual = vm_mmap(file_priv->filp, 0, dma->byte_count, PROT_READ | PROT_WRITE, MAP_SHARED, 0); - up_write(¤t->mm->mmap_sem); } if (virtual > -1024UL) { /* Real error */ diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c index 26d5197..392ce71 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c @@ -581,10 +581,8 @@ int exynos_drm_gem_mmap_ioctl(struct drm_device *dev, void *data, obj->filp->f_op = &exynos_drm_gem_fops; obj->filp->private_data = obj; - down_write(¤t->mm->mmap_sem); - addr = do_mmap(obj->filp, 0, args->size, + addr = vm_mmap(obj->filp, 0, args->size, PROT_READ | PROT_WRITE, MAP_SHARED, 0); - up_write(¤t->mm->mmap_sem); drm_gem_object_unreference_unlocked(obj); diff --git a/drivers/gpu/drm/i810/i810_dma.c b/drivers/gpu/drm/i810/i810_dma.c index b85337f..a4ba453 100644 --- a/drivers/gpu/drm/i810/i810_dma.c +++ b/drivers/gpu/drm/i810/i810_dma.c @@ -129,6 +129,7 @@ static int i810_map_buffer(struct drm_buf *buf, struct drm_file *file_priv) if (buf_priv->currently_mapped == I810_BUF_MAPPED) return -EINVAL; + /* This is all entirely broken */ down_write(¤t->mm->mmap_sem); old_fops = file_priv->filp->f_op; file_priv->filp->f_op = &i810_buffer_fops; diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 0e3c6ac..0d1e4b7 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1087,11 +1087,9 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data, if (obj == NULL) return -ENOENT; - down_write(¤t->mm->mmap_sem); - addr = do_mmap(obj->filp, 0, args->size, + addr = vm_mmap(obj->filp, 0, args->size, PROT_READ | PROT_WRITE, MAP_SHARED, args->offset); - up_write(¤t->mm->mmap_sem); drm_gem_object_unreference_unlocked(obj); if (IS_ERR((void *)addr)) return addr; -- cgit v1.1