* [PATCH] usb: clean up some of the computations in adu_read
@ 2019-06-21 6:59 dmg
2019-06-21 7:16 ` Greg KH
0 siblings, 1 reply; 4+ messages in thread
From: dmg @ 2019-06-21 6:59 UTC (permalink / raw)
To: linux-usb; +Cc: gregkh, Daniel M German
From: Daniel M German <dmg@turingmachine.org>
Replace ?: with min to calculate the number of bytes in the secondary buffer,
including changing the data type of data_in_secondary to size_t to be
type-consistent. data_in_secondary can never be negative.
Remove some spurious calculations (copy_to_user returns zero on success),
making one variable redundant (i)
This change does not alter the functionality of the code.
Signed-off-by: Daniel M German <dmg@turingmachine.org>
---
drivers/usb/misc/adutux.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 9465fb95d70a..344d523b0502 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -343,7 +343,6 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
struct adu_device *dev;
size_t bytes_read = 0;
size_t bytes_to_read = count;
- int i;
int retval = 0;
int timeout = 0;
int should_submit = 0;
@@ -371,23 +370,22 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
timeout = COMMAND_TIMEOUT;
dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__);
while (bytes_to_read) {
- int data_in_secondary = dev->secondary_tail - dev->secondary_head;
+ size_t data_in_secondary = dev->secondary_tail - dev->secondary_head;
dev_dbg(&dev->udev->dev,
- "%s : while, data_in_secondary=%d, status=%d\n",
+ "%s : while, data_in_secondary=%zu, status=%d\n",
__func__, data_in_secondary,
dev->interrupt_in_urb->status);
if (data_in_secondary) {
/* drain secondary buffer */
- int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary;
- i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount);
- if (i) {
+ size_t amount = min(bytes_to_read, data_in_secondary);
+ if (copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount)) {
retval = -EFAULT;
goto exit;
}
- dev->secondary_head += (amount - i);
- bytes_read += (amount - i);
- bytes_to_read -= (amount - i);
+ dev->secondary_head += amount;
+ bytes_read += amount;
+ bytes_to_read -= amount;
} else {
/* we check the primary buffer */
spin_lock_irqsave (&dev->buflock, flags);
--
2.20.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] usb: clean up some of the computations in adu_read
2019-06-21 6:59 [PATCH] usb: clean up some of the computations in adu_read dmg
@ 2019-06-21 7:16 ` Greg KH
2019-06-21 15:22 ` [PATCH v3] " dmg
0 siblings, 1 reply; 4+ messages in thread
From: Greg KH @ 2019-06-21 7:16 UTC (permalink / raw)
To: dmg; +Cc: linux-usb
On Thu, Jun 20, 2019 at 11:59:21PM -0700, dmg@turingmachine.org wrote:
> From: Daniel M German <dmg@turingmachine.org>
>
> Replace ?: with min to calculate the number of bytes in the secondary buffer,
> including changing the data type of data_in_secondary to size_t to be
> type-consistent. data_in_secondary can never be negative.
>
> Remove some spurious calculations (copy_to_user returns zero on success),
> making one variable redundant (i)
>
> This change does not alter the functionality of the code.
>
> Signed-off-by: Daniel M German <dmg@turingmachine.org>
> ---
> drivers/usb/misc/adutux.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
When sending a new version of a patch, you need to version it. The
documentation says how to do this, but basically you need a "v2" in the
subject line ([PATCH v2]) and then below the --- line, you need to say
what has changed from the previous version.
Can you resend a v3 of this patch that has all of that in it?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3] usb: clean up some of the computations in adu_read
2019-06-21 7:16 ` Greg KH
@ 2019-06-21 15:22 ` dmg
2019-06-21 15:55 ` dmg
0 siblings, 1 reply; 4+ messages in thread
From: dmg @ 2019-06-21 15:22 UTC (permalink / raw)
To: linux-usb; +Cc: gregkh, Daniel M German
From: Daniel M German <dmg@turingmachine.org>
Replace ?: with min to calculate the number of bytes in the secondary buffer,
including changing the data type of data_in_secondary to size_t to be
type-consistent. data_in_secondary can never be negative.
Remove some spurious calculations (copy_to_user returns zero on success),
making one variable redundant (i)
This change does not alter the functionality of the code.
Signed-off-by: Daniel M German <dmg@turingmachine.org>
---
Changes from v1:
- Replace %d modifier with %zu to avoid compilation warning
- Note that v2 was not properly labeled (its subject was [PATCH])
v2 and v3 are identical in content.
---
drivers/usb/misc/adutux.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 9465fb95d70a..344d523b0502 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -343,7 +343,6 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
struct adu_device *dev;
size_t bytes_read = 0;
size_t bytes_to_read = count;
- int i;
int retval = 0;
int timeout = 0;
int should_submit = 0;
@@ -371,23 +370,22 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
timeout = COMMAND_TIMEOUT;
dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__);
while (bytes_to_read) {
- int data_in_secondary = dev->secondary_tail - dev->secondary_head;
+ size_t data_in_secondary = dev->secondary_tail - dev->secondary_head;
dev_dbg(&dev->udev->dev,
- "%s : while, data_in_secondary=%d, status=%d\n",
+ "%s : while, data_in_secondary=%zu, status=%d\n",
__func__, data_in_secondary,
dev->interrupt_in_urb->status);
if (data_in_secondary) {
/* drain secondary buffer */
- int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary;
- i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount);
- if (i) {
+ size_t amount = min(bytes_to_read, data_in_secondary);
+ if (copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount)) {
retval = -EFAULT;
goto exit;
}
- dev->secondary_head += (amount - i);
- bytes_read += (amount - i);
- bytes_to_read -= (amount - i);
+ dev->secondary_head += amount;
+ bytes_read += amount;
+ bytes_to_read -= amount;
} else {
/* we check the primary buffer */
spin_lock_irqsave (&dev->buflock, flags);
--
2.20.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
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2019-06-21 6:59 [PATCH] usb: clean up some of the computations in adu_read dmg
2019-06-21 7:16 ` Greg KH
2019-06-21 15:22 ` [PATCH v3] " dmg
2019-06-21 15:55 ` dmg
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