Re: [PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[Adam Manzanares]

On 5/18/18 9:05 AM, Christoph Hellwig wrote:
>> +/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */
> 
> I don't think this comment is very useful.
> 
>> +static inline u16 ki_hint_valid(enum rw_hint hint)
> 
> I'd call this ki_hint_validate.
> 
>> +{
>> +if (hint > MAX_KI_HINT)
>> +return 0;
>> +
>> +return hint;
> 
> Nit: kill the empty line.
> 

I'll clean this up in the next revision.

Re: [PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[Adam Manzanares]

On 5/18/18 9:05 AM, Christoph Hellwig wrote:
>> +/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */
> 
> I don't think this comment is very useful.
> 
>> +static inline u16 ki_hint_valid(enum rw_hint hint)
> 
> I'd call this ki_hint_validate.
> 
>> +{
>> +if (hint > MAX_KI_HINT)
>> +return 0;
>> +
>> +return hint;
> 
> Nit: kill the empty line.
> 

I'll clean this up in the next revision.

Re: [PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[Christoph Hellwig]

> +/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */

I don't think this comment is very useful.

> +static inline u16 ki_hint_valid(enum rw_hint hint)

I'd call this ki_hint_validate.

> +{
> + if (hint > MAX_KI_HINT)
> + return 0;
> +
> + return hint;

Nit: kill the empty line.

Re: [PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[Christoph Hellwig]

> +/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */

I don't think this comment is very useful.

> +static inline u16 ki_hint_valid(enum rw_hint hint)

I'd call this ki_hint_validate.

> +{
> + if (hint > MAX_KI_HINT)
> + return 0;
> +
> + return hint;

Nit: kill the empty line.

[PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[adam . manzanares]

From: Adam Manzanares 

In order to avoid kiocb bloat for per command iopriority support, rw_hint
is converted from enum to a u16. Added a guard around ki_hint assigment.

Signed-off-by: Adam Manzanares 
---
 include/linux/fs.h | 15 +--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 760d8da1b6c7..7a90ce387e00 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -284,6 +284,8 @@ enum rw_hint {
WRITE_LIFE_EXTREME  = RWH_WRITE_LIFE_EXTREME,
 };
 
+#define MAX_KI_HINT((1 << 16) - 1) /* ki_hint type is u16 */
+
 #define IOCB_EVENTFD   (1 << 0)
 #define IOCB_APPEND(1 << 1)
 #define IOCB_DIRECT(1 << 2)
@@ -299,7 +301,7 @@ struct kiocb {
void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
void*private;
int ki_flags;
-   enum rw_hintki_hint;
+   u16 ki_hint;
 } __randomize_layout;
 
 static inline bool is_sync_kiocb(struct kiocb *kiocb)
@@ -1927,12 +1929,21 @@ static inline enum rw_hint file_write_hint(struct file 
*file)
 
 static inline int iocb_flags(struct file *file);
 
+/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */
+static inline u16 ki_hint_valid(enum rw_hint hint)
+{
+   if (hint > MAX_KI_HINT)
+   return 0;
+
+   return hint;
+}
+
 static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
 {
*kiocb = (struct kiocb) {
.ki_filp = filp,
.ki_flags = iocb_flags(filp),
-   .ki_hint = file_write_hint(filp),
+   .ki_hint = ki_hint_valid(file_write_hint(filp)),
};
 }
 
-- 
2.15.1

[PATCH v4 2/3] fs: Convert kiocb rw_hint from enum to u16

[adam . manzanares]

From: Adam Manzanares 

In order to avoid kiocb bloat for per command iopriority support, rw_hint
is converted from enum to a u16. Added a guard around ki_hint assigment.

Signed-off-by: Adam Manzanares 
---
 include/linux/fs.h | 15 +--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 760d8da1b6c7..7a90ce387e00 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -284,6 +284,8 @@ enum rw_hint {
WRITE_LIFE_EXTREME  = RWH_WRITE_LIFE_EXTREME,
 };
 
+#define MAX_KI_HINT((1 << 16) - 1) /* ki_hint type is u16 */
+
 #define IOCB_EVENTFD   (1 << 0)
 #define IOCB_APPEND(1 << 1)
 #define IOCB_DIRECT(1 << 2)
@@ -299,7 +301,7 @@ struct kiocb {
void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
void*private;
int ki_flags;
-   enum rw_hintki_hint;
+   u16 ki_hint;
 } __randomize_layout;
 
 static inline bool is_sync_kiocb(struct kiocb *kiocb)
@@ -1927,12 +1929,21 @@ static inline enum rw_hint file_write_hint(struct file 
*file)
 
 static inline int iocb_flags(struct file *file);
 
+/* ki_hint changed from enum to u16, make sure rw_hint fits into u16 */
+static inline u16 ki_hint_valid(enum rw_hint hint)
+{
+   if (hint > MAX_KI_HINT)
+   return 0;
+
+   return hint;
+}
+
 static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
 {
*kiocb = (struct kiocb) {
.ki_filp = filp,
.ki_flags = iocb_flags(filp),
-   .ki_hint = file_write_hint(filp),
+   .ki_hint = ki_hint_valid(file_write_hint(filp)),
};
 }
 
-- 
2.15.1