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author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2020-11-27 17:41:20 +0100 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2021-01-12 14:15:31 +0100 |
commit | eb83b8e3e6478845f8130622a2048ed4ec3b3be3 (patch) | |
tree | c328040e1c22e180852c5b51d269fc473bffdf83 /mm/frame_vector.c | |
parent | 04769cb1c45a919cd94b931e6494d2a9afc32914 (diff) | |
download | linux-eb83b8e3e6478845f8130622a2048ed4ec3b3be3.tar.gz linux-eb83b8e3e6478845f8130622a2048ed4ec3b3be3.tar.bz2 linux-eb83b8e3e6478845f8130622a2048ed4ec3b3be3.zip |
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.c | 221 |
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); |