@@ -640,16 +640,14 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
do {
unsigned int len = min_t(typeof(size), size, PAGE_SIZE);
struct page *page;
- void *pgdata, *vaddr;
+ void *pgdata;
err = aops->write_begin(file, file->f_mapping, offset, len,
&page, &pgdata);
if (err < 0)
goto fail;
- vaddr = kmap(page);
- memcpy(vaddr, data, len);
- kunmap(page);
+ memcpy_to_page(page, 0, data, len);
err = aops->write_end(file, file->f_mapping, offset, len, len,
page, pgdata);
@@ -153,7 +153,7 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj,
intel_gt_flush_ggtt_writes(to_gt(i915));
p = i915_gem_object_get_page(obj, offset >> PAGE_SHIFT);
- cpu = kmap(p) + offset_in_page(offset);
+ cpu = kmap_local_page(p) + offset_in_page(offset);
drm_clflush_virt_range(cpu, sizeof(*cpu));
if (*cpu != (u32)page) {
pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
@@ -171,7 +171,7 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj,
}
*cpu = 0;
drm_clflush_virt_range(cpu, sizeof(*cpu));
- kunmap(p);
+ kunmap_local(cpu);
out:
i915_gem_object_lock(obj, NULL);
@@ -249,7 +249,7 @@ static int check_partial_mappings(struct drm_i915_gem_object *obj,
intel_gt_flush_ggtt_writes(to_gt(i915));
p = i915_gem_object_get_page(obj, offset >> PAGE_SHIFT);
- cpu = kmap(p) + offset_in_page(offset);
+ cpu = kmap_local_page(p) + offset_in_page(offset);
drm_clflush_virt_range(cpu, sizeof(*cpu));
if (*cpu != (u32)page) {
pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
@@ -267,7 +267,7 @@ static int check_partial_mappings(struct drm_i915_gem_object *obj,
}
*cpu = 0;
drm_clflush_virt_range(cpu, sizeof(*cpu));
- kunmap(p);
+ kunmap_local(cpu);
if (err)
return err;
kmap() is being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and are still valid. Since its use in i915/gem is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in i915/gem. Instead of open-coding local map + memcpy + local unmap, use memcpy_to_page() in a suited call site. Cc: "Venkataramanan, Anirudh" <anirudh.venkataramanan@intel.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> --- drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 6 ++---- drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c | 8 ++++---- 2 files changed, 6 insertions(+), 8 deletions(-)