* [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions
@ 2025-06-19 12:37 Chelsy Ratnawat
2025-06-20 19:52 ` Christophe JAILLET
2025-06-24 23:43 ` Jarkko Sakkinen
0 siblings, 2 replies; 4+ messages in thread
From: Chelsy Ratnawat @ 2025-06-19 12:37 UTC (permalink / raw)
To: peterhuewe, jarkko; +Cc: jgg, linux-integrity, linux-kernel, Chelsy Ratnawat
Replace calls to scnprintf() with sysfs_emit() and sysfs_emit_at() in
sysfs show functions. These helpers are preferred in sysfs callbacks
because they automatically handle buffer sizing (PAGE_SIZE) and
improve safety and readability.
Signed-off-by: Chelsy Ratnawat <chelsyratnawat2001@gmail.com>
---
drivers/char/tpm/tpm_ppi.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
index bc7b1b4501b3..421c6264bac9 100644
--- a/drivers/char/tpm/tpm_ppi.c
+++ b/drivers/char/tpm/tpm_ppi.c
@@ -52,7 +52,7 @@ static ssize_t tpm_show_ppi_version(struct device *dev,
{
struct tpm_chip *chip = to_tpm_chip(dev);
- return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
+ return sysfs_emit(buf, "%s\n", chip->ppi_version);
}
static ssize_t tpm_show_ppi_request(struct device *dev,
@@ -87,11 +87,11 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
else {
req = obj->package.elements[1].integer.value;
if (tpm_ppi_req_has_parameter(req))
- size = scnprintf(buf, PAGE_SIZE,
+ size = sysfs_emit(buf,
"%llu %llu\n", req,
obj->package.elements[2].integer.value);
else
- size = scnprintf(buf, PAGE_SIZE,
+ size = sysfs_emit(buf,
"%llu\n", req);
}
} else if (obj->package.count == 2 &&
@@ -100,7 +100,7 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
if (obj->package.elements[0].integer.value)
size = -EFAULT;
else
- size = scnprintf(buf, PAGE_SIZE, "%llu\n",
+ size = sysfs_emit(buf, "%llu\n",
obj->package.elements[1].integer.value);
}
@@ -211,9 +211,9 @@ static ssize_t tpm_show_ppi_transition_action(struct device *dev,
}
if (ret < ARRAY_SIZE(info) - 1)
- status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
+ status = sysfs_emit(buf, "%d: %s\n", ret, info[ret]);
else
- status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
+ status = sysfs_emit(buf, "%d: %s\n", ret,
info[ARRAY_SIZE(info)-1]);
return status;
}
@@ -255,22 +255,22 @@ static ssize_t tpm_show_ppi_response(struct device *dev,
res = ret_obj[2].integer.value;
if (req) {
if (res == 0)
- status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+ status = sysfs_emit(buf, "%llu %s\n", req,
"0: Success");
else if (res == 0xFFFFFFF0)
- status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+ status = sysfs_emit(buf, "%llu %s\n", req,
"0xFFFFFFF0: User Abort");
else if (res == 0xFFFFFFF1)
- status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+ status = sysfs_emit(buf, "%llu %s\n", req,
"0xFFFFFFF1: BIOS Failure");
else if (res >= 1 && res <= 0x00000FFF)
- status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
+ status = sysfs_emit(buf, "%llu %llu: %s\n",
req, res, "Corresponding TPM error");
else
- status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
+ status = sysfs_emit(buf, "%llu %llu: %s\n",
req, res, "Error");
} else {
- status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
+ status = sysfs_emit(buf, "%llu: %s\n",
req, "No Recent Request");
}
@@ -314,7 +314,7 @@ static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
}
if (ret > 0 && ret < ARRAY_SIZE(info))
- str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
+ str += sysfs_emit_at(str, "%d %d: %s\n",
i, ret, info[ret]);
}
--
2.47.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions
2025-06-19 12:37 [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions Chelsy Ratnawat
@ 2025-06-20 19:52 ` Christophe JAILLET
2025-06-24 23:43 ` Jarkko Sakkinen
1 sibling, 0 replies; 4+ messages in thread
From: Christophe JAILLET @ 2025-06-20 19:52 UTC (permalink / raw)
To: Chelsy Ratnawat, peterhuewe, jarkko; +Cc: jgg, linux-integrity, linux-kernel
Le 19/06/2025 à 14:37, Chelsy Ratnawat a écrit :
> Replace calls to scnprintf() with sysfs_emit() and sysfs_emit_at() in
> sysfs show functions. These helpers are preferred in sysfs callbacks
> because they automatically handle buffer sizing (PAGE_SIZE) and
> improve safety and readability.
>
> Signed-off-by: Chelsy Ratnawat <chelsyratnawat2001@gmail.com>
> ---
> drivers/char/tpm/tpm_ppi.c | 26 +++++++++++++-------------
> 1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
> index bc7b1b4501b3..421c6264bac9 100644
> --- a/drivers/char/tpm/tpm_ppi.c
> +++ b/drivers/char/tpm/tpm_ppi.c
> @@ -52,7 +52,7 @@ static ssize_t tpm_show_ppi_version(struct device *dev,
> {
> struct tpm_chip *chip = to_tpm_chip(dev);
>
> - return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
> + return sysfs_emit(buf, "%s\n", chip->ppi_version);
> }
>
> static ssize_t tpm_show_ppi_request(struct device *dev,
> @@ -87,11 +87,11 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
> else {
> req = obj->package.elements[1].integer.value;
> if (tpm_ppi_req_has_parameter(req))
> - size = scnprintf(buf, PAGE_SIZE,
> + size = sysfs_emit(buf,
> "%llu %llu\n", req,
> obj->package.elements[2].integer.value);
> else
> - size = scnprintf(buf, PAGE_SIZE,
> + size = sysfs_emit(buf,
> "%llu\n", req);
> }
> } else if (obj->package.count == 2 &&
> @@ -100,7 +100,7 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
> if (obj->package.elements[0].integer.value)
> size = -EFAULT;
> else
> - size = scnprintf(buf, PAGE_SIZE, "%llu\n",
> + size = sysfs_emit(buf, "%llu\n",
> obj->package.elements[1].integer.value);
> }
>
> @@ -211,9 +211,9 @@ static ssize_t tpm_show_ppi_transition_action(struct device *dev,
> }
>
> if (ret < ARRAY_SIZE(info) - 1)
> - status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
> + status = sysfs_emit(buf, "%d: %s\n", ret, info[ret]);
> else
> - status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
> + status = sysfs_emit(buf, "%d: %s\n", ret,
> info[ARRAY_SIZE(info)-1]);
> return status;
> }
> @@ -255,22 +255,22 @@ static ssize_t tpm_show_ppi_response(struct device *dev,
> res = ret_obj[2].integer.value;
> if (req) {
> if (res == 0)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0: Success");
> else if (res == 0xFFFFFFF0)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0xFFFFFFF0: User Abort");
> else if (res == 0xFFFFFFF1)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0xFFFFFFF1: BIOS Failure");
> else if (res >= 1 && res <= 0x00000FFF)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
> + status = sysfs_emit(buf, "%llu %llu: %s\n",
> req, res, "Corresponding TPM error");
> else
> - status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
> + status = sysfs_emit(buf, "%llu %llu: %s\n",
> req, res, "Error");
> } else {
> - status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
> + status = sysfs_emit(buf, "%llu: %s\n",
> req, "No Recent Request");
> }
>
> @@ -314,7 +314,7 @@ static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
> }
>
> if (ret > 0 && ret < ARRAY_SIZE(info))
> - str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
> + str += sysfs_emit_at(str, "%d %d: %s\n",
sysfs_emit_at() does not work like that.
But does this code even compile?
CJ
> i, ret, info[ret]);
> }
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions
2025-06-19 12:37 [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions Chelsy Ratnawat
2025-06-20 19:52 ` Christophe JAILLET
@ 2025-06-24 23:43 ` Jarkko Sakkinen
[not found] ` <CAOeBcHNpsz5-gapd4pVO5vryENHhFrL18Mkxpe+YLndL3rY=Rw@mail.gmail.com>
1 sibling, 1 reply; 4+ messages in thread
From: Jarkko Sakkinen @ 2025-06-24 23:43 UTC (permalink / raw)
To: Chelsy Ratnawat; +Cc: peterhuewe, jgg, linux-integrity, linux-kernel
On Thu, Jun 19, 2025 at 05:37:07AM -0700, Chelsy Ratnawat wrote:
> Replace calls to scnprintf() with sysfs_emit() and sysfs_emit_at() in
> sysfs show functions. These helpers are preferred in sysfs callbacks
> because they automatically handle buffer sizing (PAGE_SIZE) and
> improve safety and readability.
>
> Signed-off-by: Chelsy Ratnawat <chelsyratnawat2001@gmail.com>
Some comments about the commit message.
Don't use "readability" as an argument as it is something that we cannot
measure, and thus useless documentation.
I neither don't understand "PAGE_SIZE" in the parentheses, or how it
"connects" to the sentence. And what do you mean exactly by safety?
Off-topic'ish:
In the Jargon world, safety is actually different than security :-)
Commercial airline planes have great safety (through redundancy)
and not as great (information) security. Just to reflect why
"safety" is neither an argument ...
> ---
> drivers/char/tpm/tpm_ppi.c | 26 +++++++++++++-------------
> 1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
> index bc7b1b4501b3..421c6264bac9 100644
> --- a/drivers/char/tpm/tpm_ppi.c
> +++ b/drivers/char/tpm/tpm_ppi.c
> @@ -52,7 +52,7 @@ static ssize_t tpm_show_ppi_version(struct device *dev,
> {
> struct tpm_chip *chip = to_tpm_chip(dev);
>
> - return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
> + return sysfs_emit(buf, "%s\n", chip->ppi_version);
> }
>
> static ssize_t tpm_show_ppi_request(struct device *dev,
> @@ -87,11 +87,11 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
> else {
> req = obj->package.elements[1].integer.value;
> if (tpm_ppi_req_has_parameter(req))
> - size = scnprintf(buf, PAGE_SIZE,
> + size = sysfs_emit(buf,
> "%llu %llu\n", req,
> obj->package.elements[2].integer.value);
> else
> - size = scnprintf(buf, PAGE_SIZE,
> + size = sysfs_emit(buf,
> "%llu\n", req);
> }
> } else if (obj->package.count == 2 &&
> @@ -100,7 +100,7 @@ static ssize_t tpm_show_ppi_request(struct device *dev,
> if (obj->package.elements[0].integer.value)
> size = -EFAULT;
> else
> - size = scnprintf(buf, PAGE_SIZE, "%llu\n",
> + size = sysfs_emit(buf, "%llu\n",
> obj->package.elements[1].integer.value);
> }
>
> @@ -211,9 +211,9 @@ static ssize_t tpm_show_ppi_transition_action(struct device *dev,
> }
>
> if (ret < ARRAY_SIZE(info) - 1)
> - status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
> + status = sysfs_emit(buf, "%d: %s\n", ret, info[ret]);
> else
> - status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
> + status = sysfs_emit(buf, "%d: %s\n", ret,
> info[ARRAY_SIZE(info)-1]);
> return status;
> }
> @@ -255,22 +255,22 @@ static ssize_t tpm_show_ppi_response(struct device *dev,
> res = ret_obj[2].integer.value;
> if (req) {
> if (res == 0)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0: Success");
> else if (res == 0xFFFFFFF0)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0xFFFFFFF0: User Abort");
> else if (res == 0xFFFFFFF1)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
> + status = sysfs_emit(buf, "%llu %s\n", req,
> "0xFFFFFFF1: BIOS Failure");
> else if (res >= 1 && res <= 0x00000FFF)
> - status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
> + status = sysfs_emit(buf, "%llu %llu: %s\n",
> req, res, "Corresponding TPM error");
> else
> - status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
> + status = sysfs_emit(buf, "%llu %llu: %s\n",
> req, res, "Error");
> } else {
> - status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
> + status = sysfs_emit(buf, "%llu: %s\n",
> req, "No Recent Request");
> }
>
> @@ -314,7 +314,7 @@ static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
> }
>
> if (ret > 0 && ret < ARRAY_SIZE(info))
> - str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
> + str += sysfs_emit_at(str, "%d %d: %s\n",
> i, ret, info[ret]);
> }
>
> --
> 2.47.1
>
BR, Jarkko
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2025-06-25 11:29 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-06-19 12:37 [PATCH] tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions Chelsy Ratnawat
2025-06-20 19:52 ` Christophe JAILLET
2025-06-24 23:43 ` Jarkko Sakkinen
[not found] ` <CAOeBcHNpsz5-gapd4pVO5vryENHhFrL18Mkxpe+YLndL3rY=Rw@mail.gmail.com>
2025-06-25 11:29 ` Jarkko Sakkinen
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox