diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/shmem_utils.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/shmem_utils.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c index 0683b27a3890..402f085f3a02 100644 --- a/drivers/gpu/drm/i915/gt/shmem_utils.c +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c @@ -3,6 +3,7 @@ * Copyright © 2020 Intel Corporation */ +#include <linux/iosys-map.h> #include <linux/mm.h> #include <linux/pagemap.h> #include <linux/shmem_fs.h> @@ -123,6 +124,37 @@ static int __shmem_rw(struct file *file, loff_t off, return 0; } +int shmem_read_to_iosys_map(struct file *file, loff_t off, + struct iosys_map *map, size_t map_off, size_t len) +{ + unsigned long pfn; + + for (pfn = off >> PAGE_SHIFT; len; pfn++) { + unsigned int this = + min_t(size_t, PAGE_SIZE - offset_in_page(off), len); + struct page *page; + void *vaddr; + + page = shmem_read_mapping_page_gfp(file->f_mapping, pfn, + GFP_KERNEL); + if (IS_ERR(page)) + return PTR_ERR(page); + + vaddr = kmap(page); + iosys_map_memcpy_to(map, map_off, vaddr + offset_in_page(off), + this); + mark_page_accessed(page); + kunmap(page); + put_page(page); + + len -= this; + map_off += this; + off = 0; + } + + return 0; +} + int shmem_read(struct file *file, loff_t off, void *dst, size_t len) { return __shmem_rw(file, off, dst, len, false); |