1 files changed, 506 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
new file mode 100644
index 000000000000..e8c94b19db7b
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
@@ -0,0 +1,506 @@
+/**************************************************************************
+ *
+ * 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"
+
+/*
+ * 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) {
+                        ttm_kunmap_atomic_prot(d->src_addr, d->src_prot);
+                        d->src_addr = NULL;
+                }
+
+                if (unmap_dst) {
+                        ttm_kunmap_atomic_prot(d->dst_addr, d->dst_prot);
+                        d->dst_addr = NULL;
+                }
+
+                if (!d->dst_addr) {
+                        if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
+                                return -EINVAL;
+
+                        d->dst_addr =
+                                ttm_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 =
+                                ttm_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;
+}
+
+/**
+ * ttm_bo_cpu_blit - in-kernel cpu blit.
+ *
+ * @dst: Destination buffer object.
+ * @dst_offset: Destination offset of blit start in bytes.
+ * @dst_stride: Destination stride in bytes.
+ * @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.
+ * 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 ttm_buffer_object *dst,
+                    u32 dst_offset, u32 dst_stride,
+                    struct ttm_buffer_object *src,
+                    u32 src_offset, u32 src_stride,
+                    u32 w, u32 h,
+                    struct vmw_diff_cpy *diff)
+{
+        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;
+        int ret = 0;
+
+        /* Buffer objects need to be either pinned or reserved: */
+        if (!(dst->mem.placement & TTM_PL_FLAG_NO_EVICT))
+                lockdep_assert_held(&dst->resv->lock.base);
+        if (!(src->mem.placement & TTM_PL_FLAG_NO_EVICT))
+                lockdep_assert_held(&src->resv->lock.base);
+
+        if (dst->ttm->state == tt_unpopulated) {
+                ret = dst->ttm->bdev->driver->ttm_tt_populate(dst->ttm, &ctx);
+                if (ret)
+                        return ret;
+        }
+
+        if (src->ttm->state == tt_unpopulated) {
+                ret = src->ttm->bdev->driver->ttm_tt_populate(src->ttm, &ctx);
+                if (ret)
+                        return ret;
+        }
+
+        d.mapped_dst = 0;
+        d.mapped_src = 0;
+        d.dst_addr = NULL;
+        d.src_addr = NULL;
+        d.dst_pages = dst->ttm->pages;
+        d.src_pages = src->ttm->pages;
+        d.dst_num_pages = dst->num_pages;
+        d.src_num_pages = src->num_pages;
+        d.dst_prot = ttm_io_prot(dst->mem.placement, PAGE_KERNEL);
+        d.src_prot = ttm_io_prot(src->mem.placement, 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)
+                ttm_kunmap_atomic_prot(d.src_addr, d.src_prot);
+        if (d.dst_addr)
+                ttm_kunmap_atomic_prot(d.dst_addr, d.dst_prot);
+
+        return ret;
+}