mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 01:41:39 +00:00
![Matthew Auld](/assets/img/avatar_default.png)
The sg_table for our backing store might contain addresses from stolen-memory or in the future local-memory, at which point this is no longer a dma-iterator. As a consequence we should now break on NULL iter.sgp, instead of dmap == 0 which is considered an invalid dma address. As a bonus, gcc much prefers this construct, Function old new delta gen8_ggtt_insert_entries 211 192 -19 gen6_ggtt_insert_entries 292 262 -30 i915_error_object_create 996 954 -42 Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20190829201919.21493-1-matthew.auld@intel.com
127 lines
3.1 KiB
C
127 lines
3.1 KiB
C
/*
|
|
* SPDX-License-Identifier: MIT
|
|
*
|
|
* Copyright © 2016 Intel Corporation
|
|
*/
|
|
|
|
#ifndef I915_SCATTERLIST_H
|
|
#define I915_SCATTERLIST_H
|
|
|
|
#include <linux/pfn.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <linux/swiotlb.h>
|
|
|
|
#include "i915_gem.h"
|
|
|
|
/*
|
|
* Optimised SGL iterator for GEM objects
|
|
*/
|
|
static __always_inline struct sgt_iter {
|
|
struct scatterlist *sgp;
|
|
union {
|
|
unsigned long pfn;
|
|
dma_addr_t dma;
|
|
};
|
|
unsigned int curr;
|
|
unsigned int max;
|
|
} __sgt_iter(struct scatterlist *sgl, bool dma) {
|
|
struct sgt_iter s = { .sgp = sgl };
|
|
|
|
if (s.sgp) {
|
|
s.max = s.curr = s.sgp->offset;
|
|
s.max += s.sgp->length;
|
|
if (dma)
|
|
s.dma = sg_dma_address(s.sgp);
|
|
else
|
|
s.pfn = page_to_pfn(sg_page(s.sgp));
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
static inline int __sg_page_count(const struct scatterlist *sg)
|
|
{
|
|
return sg->length >> PAGE_SHIFT;
|
|
}
|
|
|
|
static inline struct scatterlist *____sg_next(struct scatterlist *sg)
|
|
{
|
|
++sg;
|
|
if (unlikely(sg_is_chain(sg)))
|
|
sg = sg_chain_ptr(sg);
|
|
return sg;
|
|
}
|
|
|
|
/**
|
|
* __sg_next - return the next scatterlist entry in a list
|
|
* @sg: The current sg entry
|
|
*
|
|
* Description:
|
|
* If the entry is the last, return NULL; otherwise, step to the next
|
|
* element in the array (@sg@+1). If that's a chain pointer, follow it;
|
|
* otherwise just return the pointer to the current element.
|
|
**/
|
|
static inline struct scatterlist *__sg_next(struct scatterlist *sg)
|
|
{
|
|
return sg_is_last(sg) ? NULL : ____sg_next(sg);
|
|
}
|
|
|
|
/**
|
|
* __for_each_sgt_daddr - iterate over the device addresses of the given sg_table
|
|
* @__dp: Device address (output)
|
|
* @__iter: 'struct sgt_iter' (iterator state, internal)
|
|
* @__sgt: sg_table to iterate over (input)
|
|
* @__step: step size
|
|
*/
|
|
#define __for_each_sgt_daddr(__dp, __iter, __sgt, __step) \
|
|
for ((__iter) = __sgt_iter((__sgt)->sgl, true); \
|
|
((__dp) = (__iter).dma + (__iter).curr), (__iter).sgp; \
|
|
(((__iter).curr += (__step)) >= (__iter).max) ? \
|
|
(__iter) = __sgt_iter(__sg_next((__iter).sgp), true), 0 : 0)
|
|
|
|
/**
|
|
* for_each_sgt_page - iterate over the pages of the given sg_table
|
|
* @__pp: page pointer (output)
|
|
* @__iter: 'struct sgt_iter' (iterator state, internal)
|
|
* @__sgt: sg_table to iterate over (input)
|
|
*/
|
|
#define for_each_sgt_page(__pp, __iter, __sgt) \
|
|
for ((__iter) = __sgt_iter((__sgt)->sgl, false); \
|
|
((__pp) = (__iter).pfn == 0 ? NULL : \
|
|
pfn_to_page((__iter).pfn + ((__iter).curr >> PAGE_SHIFT))); \
|
|
(((__iter).curr += PAGE_SIZE) >= (__iter).max) ? \
|
|
(__iter) = __sgt_iter(__sg_next((__iter).sgp), false), 0 : 0)
|
|
|
|
static inline unsigned int i915_sg_page_sizes(struct scatterlist *sg)
|
|
{
|
|
unsigned int page_sizes;
|
|
|
|
page_sizes = 0;
|
|
while (sg) {
|
|
GEM_BUG_ON(sg->offset);
|
|
GEM_BUG_ON(!IS_ALIGNED(sg->length, PAGE_SIZE));
|
|
page_sizes |= sg->length;
|
|
sg = __sg_next(sg);
|
|
}
|
|
|
|
return page_sizes;
|
|
}
|
|
|
|
static inline unsigned int i915_sg_segment_size(void)
|
|
{
|
|
unsigned int size = swiotlb_max_segment();
|
|
|
|
if (size == 0)
|
|
return SCATTERLIST_MAX_SEGMENT;
|
|
|
|
size = rounddown(size, PAGE_SIZE);
|
|
/* swiotlb_max_segment_size can return 1 byte when it means one page. */
|
|
if (size < PAGE_SIZE)
|
|
size = PAGE_SIZE;
|
|
|
|
return size;
|
|
}
|
|
|
|
bool i915_sg_trim(struct sg_table *orig_st);
|
|
|
|
#endif
|