// SPDX-License-Identifier: GPL-2.0 OR MIT
/**************************************************************************
*
* Copyright 2017 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
#include "vmwgfx_drv.h"
#include "vmwgfx_bo.h"
#include <linux/highmem.h>
/*
* Template that implements find_first_diff() for a generic
* unsigned integer type. @size and return value are in bytes.
*/
#define VMW_FIND_FIRST_DIFF(_type) \
static size_t vmw_find_first_diff_ ## _type \
(const _type * dst, const _type * src, size_t size)\
{ \
size_t i; \
\
for (i = 0; i < size; i += sizeof(_type)) { \
if (*dst++ != *src++) \
break; \
} \
\
return i; \
}
/*
* Template that implements find_last_diff() for a generic
* unsigned integer type. Pointers point to the item following the
* *end* of the area to be examined. @size and return value are in
* bytes.
*/
#define VMW_FIND_LAST_DIFF(_type) \
static ssize_t vmw_find_last_diff_ ## _type( \
const _type * dst, const _type * src, size_t size) \
{ \
while (size) { \
if (*--dst != *--src) \
break; \
\
size -= sizeof(_type); \
} \
return size; \
}
/*
* Instantiate find diff functions for relevant unsigned integer sizes,
* assuming that wider integers are faster (including aligning) up to the
* architecture native width, which is assumed to be 32 bit unless
* CONFIG_64BIT is defined.
*/
VMW_FIND_FIRST_DIFF(u8);
VMW_FIND_LAST_DIFF(u8);
VMW_FIND_FIRST_DIFF(u16);
VMW_FIND_LAST_DIFF(u16);
VMW_FIND_FIRST_DIFF(u32);
VMW_FIND_LAST_DIFF(u32);
#ifdef CONFIG_64BIT
VMW_FIND_FIRST_DIFF(u64);
VMW_FIND_LAST_DIFF(u64);
#endif
/* We use size aligned copies. This computes (addr - align(addr)) */
#define SPILL(_var, _type) ((unsigned long) _var & (sizeof(_type) - 1))
/*
* Template to compute find_first_diff() for a certain integer type
* including a head copy for alignment, and adjustment of parameters
* for tail find or increased resolution find using an unsigned integer find
* of smaller width. If finding is complete, and resolution is sufficient,
* the macro executes a return statement. Otherwise it falls through.
*/
#define VMW_TRY_FIND_FIRST_DIFF(_type) \
do { \
unsigned int spill = SPILL(dst, _type); \
size_t diff_offs; \
\
if (spill && spill == SPILL(src, _type) && \
sizeof(_type) - spill <= size) { \
spill = sizeof(_type) - spill; \
diff_offs = vmw_find_first_diff_u8(dst, src, spill); \
if (diff_offs < spill) \
return round_down(offset + diff_offs, granularity); \
\
dst += spill; \
src += spill; \
size -= spill; \
offset += spill; \
spill = 0; \
} \
if (!spill && !SPILL(src, _type)) { \
size_t to_copy = size & ~(sizeof(_type) - 1); \
\
diff_offs = vmw_find_first_diff_ ## _type \
((_type *) dst, (_type *) src, to_copy); \
if (diff_offs >= size || granularity == sizeof(_type)) \
return (offset + diff_offs); \
\
dst += diff_offs; \
src += diff_offs; \
size -= diff_offs; \
offset += diff_offs; \
} \
} while (0) \
/**
* vmw_find_first_diff - find the first difference between dst and src
*
* @dst: The destination address
* @src: The source address
* @size: Number of bytes to compare
* @granularity: The granularity needed for the return value in bytes.
* return: The offset from find start where the first difference was
* encountered in bytes. If no difference was found, the function returns
* a value >= @size.
*/
static size_t vmw_find_first_diff(const u8 *dst, const u8 *src, size_t size,
size_t granularity)
{
size_t offset = 0;
/*
* Try finding with large integers if alignment allows, or we can
* fix it. Fall through if we need better resolution or alignment
* was bad.
*/
#ifdef CONFIG_64BIT
VMW_TRY_FIND_FIRST_DIFF(u64);
#endif
VMW_TRY_FIND_FIRST_DIFF(u32);
VMW_TRY_FIND_FIRST_DIFF(u16);
return round_down(offset + vmw_find_first_diff_u8(dst, src, size),
granularity);
}
/*
* Template to compute find_last_diff() for a certain integer type
* including a tail copy for alignment, and adjustment of parameters
* for head find or increased resolution find using an unsigned integer find
* of smaller width. If finding is complete, and resolution is sufficient,
* the macro executes a return statement. Otherwise it falls through.
*/
#define VMW_TRY_FIND_LAST_DIFF(_type) \
do { \
unsigned int spill = SPILL(dst, _type); \
ssize_t location; \
ssize_t diff_offs; \
\
if (spill && spill <= size && spill == SPILL(src, _type)) { \
diff_offs = vmw_find_last_diff_u8(dst, src, spill); \
if (diff_offs) { \
location = size - spill + diff_offs - 1; \
return round_down(location, granularity); \
} \
\
dst -= spill; \
src -= spill; \
size -= spill; \
spill = 0; \
} \
if (!spill && !SPILL(src, _type)) { \
size_t to_copy = round_down(size, sizeof(_type)); \
\
diff_offs = vmw_find_last_diff_ ## _type \
((_type *) dst, (_type *) src, to_copy); \
location = size - to_copy + diff_offs - sizeof(_type); \
if (location < 0 || granularity == sizeof(_type)) \
return location; \
\
dst -= to_copy - diff_offs; \
src -= to_copy - diff_offs; \
size -= to_copy - diff_offs; \
} \
} while (0)
/**
* vmw_find_last_diff - find the last difference between dst and src
*
* @dst: The destination address
* @src: The source address
* @size: Number of bytes to compare
* @granularity: The granularity needed for the return value in bytes.
* return: The offset from find start where the last difference was
* encountered in bytes, or a negative value if no difference was found.
*/
static ssize_t vmw_find_last_diff(const u8 *dst, const u8 *src, size_t size,
size_t granularity)
{
dst += size;
src += size;
#ifdef CONFIG_64BIT
VMW_TRY_FIND_LAST_DIFF(u64);
#endif
VMW_TRY_FIND_LAST_DIFF(u32);
VMW_TRY_FIND_LAST_DIFF(u16);
return round_down(vmw_find_last_diff_u8(dst, src, size) - 1,
granularity);
}
/**
* vmw_memcpy - A wrapper around kernel memcpy with allowing to plug it into a
* struct vmw_diff_cpy.
*
* @diff: The struct vmw_diff_cpy closure argument (unused).
* @dest: The copy destination.
* @src: The copy source.
* @n: Number of bytes to copy.
*/
void vmw_memcpy(struct vmw_diff_cpy *diff, u8 *dest, const u8 *src, size_t n)
{
memcpy(dest, src, n);
}
/**
* vmw_adjust_rect - Adjust rectangle coordinates for newly found difference
*
* @diff: The struct vmw_diff_cpy used to track the modified bounding box.
* @diff_offs: The offset from @diff->line_offset where the difference was
* found.
*/
static void vmw_adjust_rect(struct vmw_diff_cpy *diff, size_t diff_offs)
{
size_t offs = (diff_offs + diff->line_offset) / diff->cpp;
struct drm_rect *rect = &diff->rect;
rect->x1 = min_t(int, rect->x1, offs);
rect->x2 = max_t(int, rect->x2, offs + 1);
rect->y1 = min_t(int, rect->y1, diff->line);
rect->y2 = max_t(int, rect->y2, diff->line + 1);
}
/**
* vmw_diff_memcpy - memcpy that creates a bounding box of modified content.
*
* @diff: The struct vmw_diff_cpy used to track the modified bounding box.
* @dest: The copy destination.
* @src: The copy source.
* @n: Number of bytes to copy.
*
* In order to correctly track the modified content, the field @diff->line must
* be pre-loaded with the current line number, the field @diff->line_offset must
* be pre-loaded with the line offset in bytes where the copy starts, and
* finally the field @diff->cpp need to be preloaded with the number of bytes
* per unit in the horizontal direction of the area we're examining.
* Typically bytes per pixel.
* This is needed to know the needed granularity of the difference computing
* operations. A higher cpp generally leads to faster execution at the cost of
* bounding box width precision.
*/
void vmw_diff_memcpy(struct vmw_diff_cpy *diff, u8 *dest, const u8 *src,
size_t n)
{
ssize_t csize, byte_len;
if (WARN_ON_ONCE(round_down(n, diff->cpp) != n))
return;
/* TODO: Possibly use a single vmw_find_first_diff per line? */
csize = vmw_find_first_diff(dest, src, n, diff->cpp);
if (csize < n) {
vmw_adjust_rect(diff, csize);
byte_len = diff->cpp;
/*
* Starting from where first difference was found, find
* location of last difference, and then copy.
*/
diff->line_offset += csize;
dest += csize;
src += csize;
n -= csize;
csize = vmw_find_last_diff(dest, src, n, diff->cpp);
if (csize >= 0) {
byte_len += csize;
vmw_adjust_rect(diff, csize);
}
memcpy(dest, src, byte_len);
}
diff->line_offset += n;
}
/**
* struct vmw_bo_blit_line_data - Convenience argument to vmw_bo_cpu_blit_line
*
* @mapped_dst: Already mapped destination page index in @dst_pages.
* @dst_addr: Kernel virtual address of mapped destination page.
* @dst_pages: Array of destination bo pages.
* @dst_num_pages: Number of destination bo pages.
* @dst_prot: Destination bo page protection.
* @mapped_src: Already mapped source page index in @dst_pages.
* @src_addr: Kernel virtual address of mapped source page.
* @src_pages: Array of source bo pages.
* @src_num_pages: Number of source bo pages.
* @src_prot: Source bo page protection.
* @diff: Struct vmw_diff_cpy, in the end forwarded to the memcpy routine.
*/
struct vmw_bo_blit_line_data {
u32 mapped_dst;
u8 *dst_addr;
struct page **dst_pages;
u32 dst_num_pages;
pgprot_t dst_prot;
u32 mapped_src;
u8 *src_addr;
struct page **src_pages;
u32 src_num_pages;
pgprot_t src_prot;
struct vmw_diff_cpy *diff;
};
/**
* vmw_bo_cpu_blit_line - Blit part of a line from one bo to another.
*
* @d: Blit data as described above.
* @dst_offset: Destination copy start offset from start of bo.
* @src_offset: Source copy start offset from start of bo.
* @bytes_to_copy: Number of bytes to copy in this line.
*/
static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
u32 dst_offset,
u32 src_offset,
u32 bytes_to_copy)
{
struct vmw_diff_cpy *diff = d->diff;
while (bytes_to_copy) {
u32 copy_size = bytes_to_copy;
u32 dst_page = dst_offset >> PAGE_SHIFT;
u32 src_page = src_offset >> PAGE_SHIFT;
u32 dst_page_offset = dst_offset & ~PAGE_MASK;
u32 src_page_offset = src_offset & ~PAGE_MASK;
bool unmap_dst = d->dst_addr && dst_page != d->mapped_dst;
bool unmap_src = d->src_addr && (src_page != d->mapped_src ||
unmap_dst);
copy_size = min_t(u32, copy_size, PAGE_SIZE - dst_page_offset);
copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset);
if (unmap_src) {
kunmap_atomic(d->src_addr);
d->src_addr = NULL;
}
if (unmap_dst) {
kunmap_atomic(d->dst_addr);
d->dst_addr = NULL;
}
if (!d->dst_addr) {
if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
return -EINVAL;
d->dst_addr =
kmap_atomic_prot(d->dst_pages[dst_page],
d->dst_prot);
if (!d->dst_addr)
return -ENOMEM;
d->mapped_dst = dst_page;
}
if (!d->src_addr) {
if (WARN_ON_ONCE(src_page >= d->src_num_pages))
return -EINVAL;
d->src_addr =
kmap_atomic_prot(d->src_pages[src_page],
d->src_prot);
if (!d->src_addr)
return -ENOMEM;
d->mapped_src = src_page;
}
diff->do_cpy(diff, d->dst_addr + dst_page_offset,
d->src_addr + src_page_offset, copy_size);
bytes_to_copy -= copy_size;
dst_offset += copy_size;
src_offset += copy_size;
}
return 0;
}
static void *map_external(struct vmw_bo *bo, struct iosys_map *map)
{
struct vmw_private *vmw =
container_of(bo->tbo.bdev, struct vmw_private, bdev);
void *ptr = NULL;
int ret;
if (bo->tbo.base.import_attach) {
ret = dma_buf_vmap(bo->tbo.base.dma_buf, map);
if (ret) {
drm_dbg_driver(&vmw->drm,
"Wasn't able to map external bo!\n");
goto out;
}
ptr = map->vaddr;
} else {
ptr = vmw_bo_map_and_cache(bo);
}
out:
return ptr;
}
static void unmap_external(struct vmw_bo *bo, struct iosys_map *map)
{
if (bo->tbo.base.import_attach)
dma_buf_vunmap(bo->tbo.base.dma_buf, map);
else
vmw_bo_unmap(bo);
}
static int vmw_external_bo_copy(struct vmw_bo *dst, u32 dst_offset,
u32 dst_stride, struct vmw_bo *src,
u32 src_offset, u32 src_stride,
u32 width_in_bytes, u32 height,
struct vmw_diff_cpy *diff)
{
struct vmw_private *vmw =
container_of(dst->tbo.bdev, struct vmw_private, bdev);
size_t dst_size = dst->tbo.resource->size;
size_t src_size = src->tbo.resource->size;
struct iosys_map dst_map = {0};
struct iosys_map src_map = {0};
int ret, i;
int x_in_bytes;
u8 *vsrc;
u8 *vdst;
vsrc = map_external(src, &src_map);
if (!vsrc) {
drm_dbg_driver(&vmw->drm, "Wasn't able to map src\n");
ret = -ENOMEM;
goto out;
}
vdst = map_external(dst, &dst_map);
if (!vdst) {
drm_dbg_driver(&vmw->drm, "Wasn't able to map dst\n");
ret = -ENOMEM;
goto out;
}
vsrc += src_offset;
vdst += dst_offset;
if (src_stride == dst_stride) {
dst_size -= dst_offset;
src_size -= src_offset;
memcpy(vdst, vsrc,
min(dst_stride * height, min(dst_size, src_size)));
} else {
WARN_ON(dst_stride < width_in_bytes);
for (i = 0; i < height; ++i) {
memcpy(vdst, vsrc, width_in_bytes);
vsrc += src_stride;
vdst += dst_stride;
}
}
x_in_bytes = (dst_offset % dst_stride);
diff->rect.x1 = x_in_bytes / diff->cpp;
diff->rect.y1 = ((dst_offset - x_in_bytes) / dst_stride);
diff->rect.x2 = diff->rect.x1 + width_in_bytes / diff->cpp;
diff->rect.y2 = diff->rect.y1 + height;
ret = 0;
out:
unmap_external(src, &src_map);
unmap_external(dst, &dst_map);
return ret;
}
/**
* vmw_bo_cpu_blit - in-kernel cpu blit.
*
* @vmw_dst: Destination buffer object.
* @dst_offset: Destination offset of blit start in bytes.
* @dst_stride: Destination stride in bytes.
* @vmw_src: Source buffer object.
* @src_offset: Source offset of blit start in bytes.
* @src_stride: Source stride in bytes.
* @w: Width of blit.
* @h: Height of blit.
* @diff: The struct vmw_diff_cpy used to track the modified bounding box.
* return: Zero on success. Negative error value on failure. Will print out
* kernel warnings on caller bugs.
*
* Performs a CPU blit from one buffer object to another avoiding a full
* bo vmap which may exhaust- or fragment vmalloc space.
* On supported architectures (x86), we're using kmap_atomic which avoids
* cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems
* reference already set-up mappings.
*
* Neither of the buffer objects may be placed in PCI memory
* (Fixed memory in TTM terminology) when using this function.
*/
int vmw_bo_cpu_blit(struct vmw_bo *vmw_dst,
u32 dst_offset, u32 dst_stride,
struct vmw_bo *vmw_src,
u32 src_offset, u32 src_stride,
u32 w, u32 h,
struct vmw_diff_cpy *diff)
{
struct ttm_buffer_object *src = &vmw_src->tbo;
struct ttm_buffer_object *dst = &vmw_dst->tbo;
struct ttm_operation_ctx ctx = {
.interruptible = false,
.no_wait_gpu = false
};
u32 j, initial_line = dst_offset / dst_stride;
struct vmw_bo_blit_line_data d = {0};
int ret = 0;
struct page **dst_pages = NULL;
struct page **src_pages = NULL;
bool src_external = (src->ttm->page_flags & TTM_TT_FLAG_EXTERNAL) != 0;
bool dst_external = (dst->ttm->page_flags & TTM_TT_FLAG_EXTERNAL) != 0;
if (WARN_ON(dst == src))
return -EINVAL;
/* Buffer objects need to be either pinned or reserved: */
if (!(dst->pin_count))
dma_resv_assert_held(dst->base.resv);
if (!(src->pin_count))
dma_resv_assert_held(src->base.resv);
if (!ttm_tt_is_populated(dst->ttm)) {
ret = dst->bdev->funcs->ttm_tt_populate(dst->bdev, dst->ttm, &ctx);
if (ret)
return ret;
}
if (!ttm_tt_is_populated(src->ttm)) {
ret = src->bdev->funcs->ttm_tt_populate(src->bdev, src->ttm, &ctx);
if (ret)
return ret;
}
if (src_external || dst_external)
return vmw_external_bo_copy(vmw_dst, dst_offset, dst_stride,
vmw_src, src_offset, src_stride,
w, h, diff);
if (!src->ttm->pages && src->ttm->sg) {
src_pages = kvmalloc_array(src->ttm->num_pages,
sizeof(struct page *), GFP_KERNEL);
if (!src_pages)
return -ENOMEM;
ret = drm_prime_sg_to_page_array(src->ttm->sg, src_pages,
src->ttm->num_pages);
if (ret)
goto out;
}
if (!dst->ttm->pages && dst->ttm->sg) {
dst_pages = kvmalloc_array(dst->ttm->num_pages,
sizeof(struct page *), GFP_KERNEL);
if (!dst_pages) {
ret = -ENOMEM;
goto out;
}
ret = drm_prime_sg_to_page_array(dst->ttm->sg, dst_pages,
dst->ttm->num_pages);
if (ret)
goto out;
}
d.mapped_dst = 0;
d.mapped_src = 0;
d.dst_addr = NULL;
d.src_addr = NULL;
d.dst_pages = dst->ttm->pages ? dst->ttm->pages : dst_pages;
d.src_pages = src->ttm->pages ? src->ttm->pages : src_pages;
d.dst_num_pages = PFN_UP(dst->resource->size);
d.src_num_pages = PFN_UP(src->resource->size);
d.dst_prot = ttm_io_prot(dst, dst->resource, PAGE_KERNEL);
d.src_prot = ttm_io_prot(src, src->resource, PAGE_KERNEL);
d.diff = diff;
for (j = 0; j < h; ++j) {
diff->line = j + initial_line;
diff->line_offset = dst_offset % dst_stride;
ret = vmw_bo_cpu_blit_line(&d, dst_offset, src_offset, w);
if (ret)
goto out;
dst_offset += dst_stride;
src_offset += src_stride;
}
out:
if (d.src_addr)
kunmap_atomic(d.src_addr);
if (d.dst_addr)
kunmap_atomic(d.dst_addr);
if (src_pages)
kvfree(src_pages);
if (dst_pages)
kvfree(dst_pages);
return ret;
}
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