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authorLinus Torvalds <torvalds@linux-foundation.org>2021-02-22 17:45:02 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-02-22 17:45:02 -0800
commite913a8cdc297d51c832bb8e9914333b6ae3fe6ef (patch)
tree338c88d3eba453db70714811d44488af6f8cee1f /drivers/media
parent4b5f9254e4f4375ac845cb17f1732037dd8adeeb (diff)
parent636b21b50152d4e203223ee337aca1cb3c1bfe53 (diff)
Merge tag 'topic/iomem-mmap-vs-gup-2021-02-22' of git://anongit.freedesktop.org/drm/drm
Pull follow_pfn() updates from Daniel Vetter: "Fixes around VM_FPNMAP and follow_pfn: - replace mm/frame_vector.c by get_user_pages in misc/habana and drm/exynos drivers, then move that into media as it's sole user - close race in generic_access_phys - s390 pci ioctl fix of this series landed in 5.11 already - properly revoke iomem mappings (/dev/mem, pci files)" * tag 'topic/iomem-mmap-vs-gup-2021-02-22' of git://anongit.freedesktop.org/drm/drm: PCI: Revoke mappings like devmem PCI: Also set up legacy files only after sysfs init sysfs: Support zapping of binary attr mmaps resource: Move devmem revoke code to resource framework /dev/mem: Only set filp->f_mapping PCI: Obey iomem restrictions for procfs mmap mm: Close race in generic_access_phys media: videobuf2: Move frame_vector into media subsystem mm/frame-vector: Use FOLL_LONGTERM misc/habana: Use FOLL_LONGTERM for userptr misc/habana: Stop using frame_vector helpers drm/exynos: Use FOLL_LONGTERM for g2d cmdlists drm/exynos: Stop using frame_vector helpers
Diffstat (limited to 'drivers/media')
-rw-r--r--drivers/media/common/videobuf2/Kconfig1
-rw-r--r--drivers/media/common/videobuf2/Makefile1
-rw-r--r--drivers/media/common/videobuf2/frame_vector.c223
-rw-r--r--drivers/media/common/videobuf2/videobuf2-memops.c3
-rw-r--r--drivers/media/platform/omap/Kconfig1
5 files changed, 225 insertions, 4 deletions
diff --git a/drivers/media/common/videobuf2/Kconfig b/drivers/media/common/videobuf2/Kconfig
index edbc99ebba87..d2223a12c95f 100644
--- a/drivers/media/common/videobuf2/Kconfig
+++ b/drivers/media/common/videobuf2/Kconfig
@@ -9,7 +9,6 @@ config VIDEOBUF2_V4L2
config VIDEOBUF2_MEMOPS
tristate
- select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate
diff --git a/drivers/media/common/videobuf2/Makefile b/drivers/media/common/videobuf2/Makefile
index 77bebe8b202f..54306f8d096c 100644
--- a/drivers/media/common/videobuf2/Makefile
+++ b/drivers/media/common/videobuf2/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
videobuf2-common-objs := videobuf2-core.o
+videobuf2-common-objs += frame_vector.o
ifeq ($(CONFIG_TRACEPOINTS),y)
videobuf2-common-objs += vb2-trace.o
diff --git a/drivers/media/common/videobuf2/frame_vector.c b/drivers/media/common/videobuf2/frame_vector.c
new file mode 100644
index 000000000000..a0e65481a201
--- /dev/null
+++ b/drivers/media/common/videobuf2/frame_vector.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+#include <media/frame_vector.h>
+
+/**
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @gup_flags: flags modifying lookup behaviour
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_lock as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ start = untagged_addr(start);
+
+ ret = pin_user_pages_fast(start, nr_frames,
+ FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM,
+ (struct page **)(vec->ptrs));
+ if (ret > 0) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ goto out_unlocked;
+ }
+
+ mmap_read_lock(mm);
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ ret = 0;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma)
+ break;
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /* Bail out if VMA doesn't completely cover the tail page. */
+ if (start < vma->vm_end)
+ break;
+ } while (ret < nr_frames);
+out:
+ mmap_read_unlock(mm);
+out_unlocked:
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+
+ unpin_user_pages(pages, vec->nr_frames);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ vec = kvmalloc(size, GFP_KERNEL);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ kvfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/drivers/media/common/videobuf2/videobuf2-memops.c b/drivers/media/common/videobuf2/videobuf2-memops.c
index 6e9e05153f4e..9dd6c27162f4 100644
--- a/drivers/media/common/videobuf2/videobuf2-memops.c
+++ b/drivers/media/common/videobuf2/videobuf2-memops.c
@@ -40,7 +40,6 @@ struct frame_vector *vb2_create_framevec(unsigned long start,
unsigned long first, last;
unsigned long nr;
struct frame_vector *vec;
- unsigned int flags = FOLL_FORCE | FOLL_WRITE;
first = start >> PAGE_SHIFT;
last = (start + length - 1) >> PAGE_SHIFT;
@@ -48,7 +47,7 @@ struct frame_vector *vb2_create_framevec(unsigned long start,
vec = frame_vector_create(nr);
if (!vec)
return ERR_PTR(-ENOMEM);
- ret = get_vaddr_frames(start & PAGE_MASK, nr, flags, vec);
+ ret = get_vaddr_frames(start & PAGE_MASK, nr, vec);
if (ret < 0)
goto out_destroy;
/* We accept only complete set of PFNs */
diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
index f73b5893220d..de16de46c0f4 100644
--- a/drivers/media/platform/omap/Kconfig
+++ b/drivers/media/platform/omap/Kconfig
@@ -12,6 +12,5 @@ config VIDEO_OMAP2_VOUT
depends on VIDEO_V4L2
select VIDEOBUF2_DMA_CONTIG
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
- select FRAME_VECTOR
help
V4L2 Display driver support for OMAP2/3 based boards.