fat: Use cache aligned buffers for fat_opendir

PATCH In review Neil Armstrong 4 participants 4 messages Nov 24, 2017 – Nov 30, 2017 VFAT/FAT/msdos filesystem

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Neil Armstrong

author

2017-11-24 08:54 UTC #0 lore raw

PATCH 1/1 fat: Use cache aligned buffers for fat_opendir

Before this patch one could receive following errors when executing "fatls" command on machine with cache enabled (ex i.MX6Q) :

=> fatls mmc 0:1
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8

To alleviate this problem - the calloc()s have been replaced with malloc_cache_aligned() and memset().

After those changes the buffers are properly aligned (with both start address and size) to SoC cache line.

Fixes 09fa964bba80 ("fs/fat: Fix 'CACHE: Misaligned operation at range' warnings")

Signed-off-by Neil Armstrong <[email protected]>

---
 fs/fat/fat.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

fs/fat/fat.c +3 -1

index 7fe7843..d16883f 100644
@@ -1149,11 +1149,13 @@ typedef struct {
 
 int fat_opendir(const char *filename, struct fs_dir_stream **dirsp)
 {
-	fat_dir *dir = calloc(1, sizeof(*dir));
+	fat_dir *dir;
 	int ret;
 
+	dir = malloc_cache_aligned(sizeof(*dir));
 	if (!dir)
 		return -ENOMEM;
+	memset(dir, 0, sizeof(*dir));
 
 	ret = fat_itr_root(&dir->itr, &dir->fsdata);
 	if (ret)

Signature · 1 line

2.7.4

Lukasz Majewski

2017-11-24 09:04 UTC #1 lore raw

PATCH 1/1 fat: Use cache aligned buffers for fat_opendir

Quoted 36 lines · On Fri, 24 Nov 2017 09:54:41 +0100 Neil Armstrong <[email protected]>…

Before this patch one could receive following errors when executing "fatls" command on machine with cache enabled (ex i.MX6Q) :
=> fatls mmc 0:1
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8 ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8 CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8] CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8 ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
To alleviate this problem - the calloc()s have been replaced with malloc_cache_aligned() and memset().
After those changes the buffers are properly aligned (with both start address and size) to SoC cache line.
Fixes 09fa964bba80 ("fs/fat: Fix 'CACHE: Misaligned operation at
range' warnings") Suggested-by: Lukasz Majewski <[email protected]>
Signed-off-by Neil Armstrong <[email protected]>
---
 fs/fat/fat.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
fs/fat/fat.c +0 -1
index 7fe7843..d16883f 100644
@@ -1149,11 +1149,13 @@ typedef struct {
 
 int fat_opendir(const char *filename, struct fs_dir_stream **dirsp)
 {
-	fat_dir *dir = calloc(1, sizeof(*dir));

fs/fat/fat.c typedef struct { · line 1161

Quoted 10 lines

fs/fat/fat.c +3 -0

+	fat_dir *dir;
 	int ret;
 
+	dir = malloc_cache_aligned(sizeof(*dir));
 	if (!dir)
 		return -ENOMEM;
+	memset(dir, 0, sizeof(*dir));
 
 	ret = fat_itr_root(&dir->itr, &dir->fsdata);
 	if (ret)

Reviewed-by Lukasz Majewski <[email protected]>

Best regards,

Lukasz Majewski

DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de -------------- next part --------------
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Fabio Estevam

2017-11-24 13:31 UTC #2 lore raw

PATCH 1/1 fat: Use cache aligned buffers for fat_opendir

In reply to Neil Armstrong

Hi Neil,

Quoted 16 lines · Neil Armstrong

Before this patch one could receive following errors when executing "fatls" command on machine with cache enabled (ex i.MX6Q) :
=> fatls mmc 0:1
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
To alleviate this problem - the calloc()s have been replaced with malloc_cache_aligned() and memset().

Quoted 6 lines

After those changes the buffers are properly aligned (with both start address and size) to SoC cache line.
Fixes 09fa964bba80 ("fs/fat: Fix 'CACHE: Misaligned operation at range' warnings")
Suggested-by Lukasz Majewski <[email protected]>
Signed-off-by Neil Armstrong <[email protected]>

Thanks for the fix:

Reviewed-by Fabio Estevam <[email protected]>

Tom Rini

2017-11-30 15:36 UTC #3 lore raw

In reply to Neil Armstrong

Quoted 16 lines · Neil Armstrong

Before this patch one could receive following errors when executing "fatls" command on machine with cache enabled (ex i.MX6Q) :
=> fatls mmc 0:1
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
CACHE: Misaligned operation at range [4f59dfc8, 4f59e7c8]
ERROR: v7_outer_cache_inval_range - start address is not aligned - 0x4f59dfc8
ERROR: v7_outer_cache_inval_range - stop address is not aligned - 0x4f59e7c8
To alleviate this problem - the calloc()s have been replaced with malloc_cache_aligned() and memset().

Quoted 8 lines

After those changes the buffers are properly aligned (with both start address and size) to SoC cache line.
Fixes 09fa964bba80 ("fs/fat: Fix 'CACHE: Misaligned operation at range' warnings")
Suggested-by Lukasz Majewski <[email protected]>
Signed-off-by Neil Armstrong <[email protected]>
Reviewed-by Lukasz Majewski <[email protected]>
Reviewed-by Fabio Estevam <[email protected]>

Applied to u-boot/master, thanks!

Signature · 8 lines

Tom
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