summaryrefslogtreecommitdiff
path: root/mm/frame_vector.c
diff options
context:
space:
mode:
authorDaniel Vetter <daniel.vetter@ffwll.ch>2020-11-27 17:41:20 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2021-01-12 14:15:31 +0100
commiteb83b8e3e6478845f8130622a2048ed4ec3b3be3 (patch)
treec328040e1c22e180852c5b51d269fc473bffdf83 /mm/frame_vector.c
parent04769cb1c45a919cd94b931e6494d2a9afc32914 (diff)
media: videobuf2: Move frame_vector into media subsystem
It's the only user. This also garbage collects the CONFIG_FRAME_VECTOR symbol from all over the tree (well just one place, somehow omap media driver still had this in its Kconfig, despite not using it). Reviewed-by: John Hubbard <jhubbard@nvidia.com> Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Acked-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: Tomasz Figa <tfiga@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Pawel Osciak <pawel@osciak.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Tomasz Figa <tfiga@chromium.org> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-7-daniel.vetter@ffwll.ch
Diffstat (limited to 'mm/frame_vector.c')
-rw-r--r--mm/frame_vector.c221
1 files changed, 0 insertions, 221 deletions
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
deleted file mode 100644
index f8c34b895c76..000000000000
--- a/mm/frame_vector.c
+++ /dev/null
@@ -1,221 +0,0 @@
-// 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>
-
-/**
- * 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);