linux/drivers/media/common/videobuf2/frame_vector.c
Hans Verkuil a4184b4f99 media: fix incorrect kernel doc usages
This patch fixes the following trivial warnings w.r.t. kernel-doc usage:

drivers/media/common/videobuf2/frame_vector.c:38: warning: Excess function parameter 'gup_flags' description in 'get_vaddr_frames'
drivers/media/dvb-core/dvb_ca_en50221.c:193: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1014: warning: expecting prototype for Wake up the DVB CA thread(). Prototype was for
dvb_ca_en50221_thread_wakeup() instead
drivers/media/dvb-core/dvb_ca_en50221.c:1023: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1081: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1112: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1327: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1411: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1426: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1582: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1693: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1743: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1772: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1830: warning: wrong kernel-doc identifier on line:
drivers/media/dvb-core/dvb_ca_en50221.c:1922: warning: wrong kernel-doc identifier on line:
drivers/media/rc/img-ir/img-ir-hw.c:628: warning: expecting prototype for img_ir_decoder_compatable(). Prototype was for
img_ir_decoder_compatible() instead
drivers/media/v4l2-core/v4l2-jpeg.c:461: warning: expecting prototype for jpeg_parse_header(). Prototype was for v4l2_jpeg_parse_header()
instead
drivers/media/platform/vsp1/vsp1_dl.c:166: warning: expecting prototype for struct vsp1_cmd_pool. Prototype was for struct vsp1_dl_cmd_pool
instead
drivers/media/platform/mtk-vpu/mtk_vpu.c:28: warning: expecting prototype for is a tiny processor controlling video hardware(). Prototype
was for INIT_TIMEOUT_MS() instead
drivers/media/platform/mtk-vcodec/vdec/vdec_vp9_if.c:73: warning: expecting prototype for struct vp9_fb_info. Prototype was for struct
vp9_ref_buf instead
drivers/media/platform/mtk-vcodec/vdec/vdec_vp9_if.c:85: warning: expecting prototype for struct vp9_fb_info. Prototype was for struct
vp9_sf_ref_fb instead
drivers/media/tuners/mt2063.c:1404: warning: expecting prototype for fLO_FractionalTerm(). Prototype was for MT2063_fLO_FractionalTerm() instead
drivers/media/tuners/mt2063.c:1465: warning: expecting prototype for CalcLO2Mult(). Prototype was for MT2063_CalcLO2Mult() instead
drivers/media/usb/pwc/pwc-dec23.c:640: warning: wrong kernel-doc identifier on line:
drivers/media/platform/exynos4-is/media-dev.c:820: warning: expecting prototype for __fimc_md_create_fimc_links(). Prototype was for
__fimc_md_create_fimc_sink_links() instead
drivers/media/i2c/s5k6aa.c:426: warning: expecting prototype for s5k6aa_configure_pixel_clock(). Prototype was for
s5k6aa_configure_pixel_clocks() instead
drivers/media/i2c/imx274.c:700: warning: wrong kernel-doc identifier on line:
drivers/media/i2c/imx274.c:735: warning: wrong kernel-doc identifier on line:
drivers/media/i2c/imx274.c:983: warning: wrong kernel-doc identifier on line:

Most are missing or mistyped function names.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-11 11:59:44 +01:00

223 lines
5.8 KiB
C

// 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
* @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);