2021-10-12 05:57:00

by Hamza Mahfooz

[permalink] [raw]
Subject: [PATCH] dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC

Mapping something twice should be possible as long as,
DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant
mapping operation (that attempts to map the same thing). So, don't issue a
warning if the specified condition is met in add_dma_entry().

Signed-off-by: Hamza Mahfooz <[email protected]>
---
kernel/dma/debug.c | 24 ++++++++++++++----------
kernel/dma/debug.h | 24 ++++++++++++++++--------
kernel/dma/mapping.c | 12 ++++++------
3 files changed, 36 insertions(+), 24 deletions(-)

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 95445bd6eb72..c4128df3de41 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -552,7 +552,7 @@ static void active_cacheline_remove(struct dma_debug_entry *entry)
* Wrapper function for adding an entry to the hash.
* This function takes care of locking itself.
*/
-static void add_dma_entry(struct dma_debug_entry *entry)
+static void add_dma_entry(struct dma_debug_entry *entry, unsigned long attrs)
{
struct hash_bucket *bucket;
unsigned long flags;
@@ -566,7 +566,7 @@ static void add_dma_entry(struct dma_debug_entry *entry)
if (rc == -ENOMEM) {
pr_err("cacheline tracking ENOMEM, dma-debug disabled\n");
global_disable = true;
- } else if (rc == -EEXIST) {
+ } else if ((rc == -EEXIST) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
err_printk(entry->dev, entry,
"cacheline tracking EEXIST, overlapping mappings aren't supported\n");
}
@@ -1191,7 +1191,8 @@ void debug_dma_map_single(struct device *dev, const void *addr,
EXPORT_SYMBOL(debug_dma_map_single);

void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
- size_t size, int direction, dma_addr_t dma_addr)
+ size_t size, int direction, dma_addr_t dma_addr,
+ unsigned long attrs)
{
struct dma_debug_entry *entry;

@@ -1222,7 +1223,7 @@ void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
check_for_illegal_area(dev, addr, size);
}

- add_dma_entry(entry);
+ add_dma_entry(entry, attrs);
}

void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
@@ -1280,7 +1281,8 @@ void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
}

void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
- int nents, int mapped_ents, int direction)
+ int nents, int mapped_ents, int direction,
+ unsigned long attrs)
{
struct dma_debug_entry *entry;
struct scatterlist *s;
@@ -1312,7 +1314,7 @@ void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,

check_sg_segment(dev, s);

- add_dma_entry(entry);
+ add_dma_entry(entry, attrs);
}
}

@@ -1368,7 +1370,8 @@ void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
}

void debug_dma_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t dma_addr, void *virt)
+ dma_addr_t dma_addr, void *virt,
+ unsigned long attrs)
{
struct dma_debug_entry *entry;

@@ -1398,7 +1401,7 @@ void debug_dma_alloc_coherent(struct device *dev, size_t size,
else
entry->pfn = page_to_pfn(virt_to_page(virt));

- add_dma_entry(entry);
+ add_dma_entry(entry, attrs);
}

void debug_dma_free_coherent(struct device *dev, size_t size,
@@ -1429,7 +1432,8 @@ void debug_dma_free_coherent(struct device *dev, size_t size,
}

void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
- int direction, dma_addr_t dma_addr)
+ int direction, dma_addr_t dma_addr,
+ unsigned long attrs)
{
struct dma_debug_entry *entry;

@@ -1449,7 +1453,7 @@ void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
entry->direction = direction;
entry->map_err_type = MAP_ERR_NOT_CHECKED;

- add_dma_entry(entry);
+ add_dma_entry(entry, attrs);
}

void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
diff --git a/kernel/dma/debug.h b/kernel/dma/debug.h
index 83643b3010b2..f525197d3cae 100644
--- a/kernel/dma/debug.h
+++ b/kernel/dma/debug.h
@@ -11,26 +11,30 @@
#ifdef CONFIG_DMA_API_DEBUG
extern void debug_dma_map_page(struct device *dev, struct page *page,
size_t offset, size_t size,
- int direction, dma_addr_t dma_addr);
+ int direction, dma_addr_t dma_addr,
+ unsigned long attrs);

extern void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
size_t size, int direction);

extern void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
- int nents, int mapped_ents, int direction);
+ int nents, int mapped_ents, int direction,
+ unsigned long attrs);

extern void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
int nelems, int dir);

extern void debug_dma_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t dma_addr, void *virt);
+ dma_addr_t dma_addr, void *virt,
+ unsigned long attrs);

extern void debug_dma_free_coherent(struct device *dev, size_t size,
void *virt, dma_addr_t addr);

extern void debug_dma_map_resource(struct device *dev, phys_addr_t addr,
size_t size, int direction,
- dma_addr_t dma_addr);
+ dma_addr_t dma_addr,
+ unsigned long attrs);

extern void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
size_t size, int direction);
@@ -53,7 +57,8 @@ extern void debug_dma_sync_sg_for_device(struct device *dev,
#else /* CONFIG_DMA_API_DEBUG */
static inline void debug_dma_map_page(struct device *dev, struct page *page,
size_t offset, size_t size,
- int direction, dma_addr_t dma_addr)
+ int direction, dma_addr_t dma_addr,
+ unsigned long attrs)
{
}

@@ -63,7 +68,8 @@ static inline void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
}

static inline void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
- int nents, int mapped_ents, int direction)
+ int nents, int mapped_ents, int direction,
+ unsigned long attrs)
{
}

@@ -74,7 +80,8 @@ static inline void debug_dma_unmap_sg(struct device *dev,
}

static inline void debug_dma_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t dma_addr, void *virt)
+ dma_addr_t dma_addr, void *virt,
+ unsigned long attrs)
{
}

@@ -85,7 +92,8 @@ static inline void debug_dma_free_coherent(struct device *dev, size_t size,

static inline void debug_dma_map_resource(struct device *dev, phys_addr_t addr,
size_t size, int direction,
- dma_addr_t dma_addr)
+ dma_addr_t dma_addr,
+ unsigned long attrs)
{
}

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 06fec5547e7c..17c6d217f8fb 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -156,7 +156,7 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
else
addr = ops->map_page(dev, page, offset, size, dir, attrs);
- debug_dma_map_page(dev, page, offset, size, dir, addr);
+ debug_dma_map_page(dev, page, offset, size, dir, addr, attrs);

return addr;
}
@@ -195,7 +195,7 @@ static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
ents = ops->map_sg(dev, sg, nents, dir, attrs);

if (ents > 0)
- debug_dma_map_sg(dev, sg, nents, ents, dir);
+ debug_dma_map_sg(dev, sg, nents, ents, dir, attrs);
else if (WARN_ON_ONCE(ents != -EINVAL && ents != -ENOMEM &&
ents != -EIO))
return -EIO;
@@ -305,7 +305,7 @@ dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
else if (ops->map_resource)
addr = ops->map_resource(dev, phys_addr, size, dir, attrs);

- debug_dma_map_resource(dev, phys_addr, size, dir, addr);
+ debug_dma_map_resource(dev, phys_addr, size, dir, addr, attrs);
return addr;
}
EXPORT_SYMBOL(dma_map_resource);
@@ -510,7 +510,7 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
else
return NULL;

- debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
+ debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr, attrs);
return cpu_addr;
}
EXPORT_SYMBOL(dma_alloc_attrs);
@@ -566,7 +566,7 @@ struct page *dma_alloc_pages(struct device *dev, size_t size,
struct page *page = __dma_alloc_pages(dev, size, dma_handle, dir, gfp);

if (page)
- debug_dma_map_page(dev, page, 0, size, dir, *dma_handle);
+ debug_dma_map_page(dev, page, 0, size, dir, *dma_handle, 0);
return page;
}
EXPORT_SYMBOL_GPL(dma_alloc_pages);
@@ -644,7 +644,7 @@ struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,

if (sgt) {
sgt->nents = 1;
- debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir);
+ debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir, attrs);
}
return sgt;
}
--
2.33.0