* [PATCH v2 1/2] lib/cmdline: add new function get_option_ull()
2021-01-16 10:41 [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform Wesley Zhao
@ 2021-01-16 10:41 ` Wesley Zhao
2021-01-17 19:02 ` [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform Dan Williams
2021-01-18 10:42 ` Andy Shevchenko
2 siblings, 0 replies; 6+ messages in thread
From: Wesley Zhao @ 2021-01-16 10:41 UTC (permalink / raw)
To: akpm
Cc: andriy.shevchenko, keescook, tglx, kerneldev, nivedita, joe,
gpiccoli, aquini, gustavoars, zhaowei1102, ojeda, ndesaulniers,
linux-kernel, david, dan.j.williams, guohanjun, mchehab+huawei
In the future we would pass the unsigned long long parameter
like(0x123456781234) in cmdline on the 64bit platform, so add a new
option parse function get_option_ull()
Signed-off-by: Wesley Zhao <zhaowei1102@thundersoft.com>
---
include/linux/kernel.h | 2 ++
lib/cmdline.c | 94 ++++++++++++++++++++++++++++++++++++++++++--------
2 files changed, 82 insertions(+), 14 deletions(-)
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index f7902d8c1048..eb1f0b14a0c5 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -348,6 +348,8 @@ extern __scanf(2, 0)
int vsscanf(const char *, const char *, va_list);
extern int get_option(char **str, int *pint);
+extern int get_option_ll(char **str, long long *pll);
+extern int get_option_ull(char **str, unsigned long long *pull);
extern char *get_options(const char *str, int nints, int *ints);
extern unsigned long long memparse(const char *ptr, char **retptr);
extern bool parse_option_str(const char *str, const char *option);
diff --git a/lib/cmdline.c b/lib/cmdline.c
index b390dd03363b..d32b585d287d 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -31,6 +31,81 @@ static int get_range(char **str, int *pint, int n)
*pint++ = x;
return inc_counter;
}
+/**
+ * get_option_ull - Parse unsigned long long from an option string
+ * @str: option string
+ * @pull: (output) unsigned long long value parsed from @str
+ *
+ * Read an unsigned long long from an option string; if available accept a subsequent
+ * comma as well.
+ *
+ * Return values:
+ * 0 - no ull in string
+ * 1 - ull found, no subsequent comma
+ * 2 - ull found including a subsequent comma
+ * 3 - hyphen found to denote a range
+ */
+
+int get_option_ull(char **str, unsigned long long *pull)
+{
+ char *cur = *str;
+ unsigned long long value;
+
+ if (!cur || !(*cur))
+ return 0;
+ value = simple_strtoull(cur, str, 0);
+ if (pull)
+ *pull = value;
+ if (cur == *str)
+ return 0;
+ if (**str == ',') {
+ (*str)++;
+ return 2;
+ }
+ if (**str == '-')
+ return 3;
+
+ return 1;
+}
+EXPORT_SYMBOL(get_option_ull);
+
+/**
+ * get_option_ll - Parse long long from an option string
+ * @str: option string
+ * @pll: (output) long long value parsed from @str
+ *
+ * Read an long long from an option string; if available accept a subsequent
+ * comma as well.
+ *
+ * Return values:
+ * 0 - no ll in string
+ * 1 - ll found, no subsequent comma
+ * 2 - ll found including a subsequent comma
+ * 3 - hyphen found to denote a range
+ */
+
+int get_option_ll(char **str, long long *pll)
+{
+ char *cur = *str;
+ unsigned long long value;
+ int ret;
+
+ if (!cur || !(*cur))
+ return 0;
+ if (*cur == '-') {
+ cur = cur + 1;
+ ret = get_option_ull((char **)&cur, &value);
+ if (pll)
+ *pll = -value;
+ } else {
+ ret = get_option_ull(str, &value);
+ if (pll)
+ *pll = value;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(get_option_ll);
/**
* get_option - Parse integer from an option string
@@ -56,26 +131,17 @@ static int get_range(char **str, int *pint, int n)
int get_option(char **str, int *pint)
{
char *cur = *str;
- int value;
+ long long value;
+ int ret;
if (!cur || !(*cur))
return 0;
- if (*cur == '-')
- value = -simple_strtoull(++cur, str, 0);
- else
- value = simple_strtoull(cur, str, 0);
+ ret = get_option_ll(str, &value);
+
if (pint)
*pint = value;
- if (cur == *str)
- return 0;
- if (**str == ',') {
- (*str)++;
- return 2;
- }
- if (**str == '-')
- return 3;
- return 1;
+ return ret;
}
EXPORT_SYMBOL(get_option);
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform
2021-01-16 10:41 [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform Wesley Zhao
2021-01-16 10:41 ` [PATCH v2 1/2] lib/cmdline: add new function get_option_ull() Wesley Zhao
@ 2021-01-17 19:02 ` Dan Williams
[not found] ` <202101181151049299923@thundersoft.com>
2021-01-18 10:42 ` Andy Shevchenko
2 siblings, 1 reply; 6+ messages in thread
From: Dan Williams @ 2021-01-17 19:02 UTC (permalink / raw)
To: Wesley Zhao
Cc: Andrew Morton, Andy Shevchenko, Kees Cook, Thomas Gleixner,
kerneldev, Arvind Sankar, Joe Perches, gpiccoli, aquini,
gustavoars, ojeda, ndesaulniers, Linux Kernel Mailing List,
David Hildenbrand, guohanjun, mchehab+huawei
On Sat, Jan 16, 2021 at 2:43 AM Wesley Zhao <zhaowei1102@thundersoft.com> wrote:
>
> I was trying to reserve some memory to save logs incase that Android panic or hang and then
> I can read the logs from QNX side from the memory reserved before on the Qualcomm 8155 hypervisor platform,
> and I find the "reserve=" parameter only support 32bit,so I made some change and send these patches.
See Documentation/admin-guide/kernel-parameters.txt
memmap=nn[KMG]$ss[KMG]
[KNL,ACPI] Mark specific memory as reserved.
Region of memory to be reserved is from ss to ss+nn.
Example: Exclude memory from 0x18690000-0x1869ffff
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
Some bootloaders may need an escape character
before '$',
like Grub2, otherwise '$' and the following number
will be eaten.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform
2021-01-16 10:41 [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform Wesley Zhao
2021-01-16 10:41 ` [PATCH v2 1/2] lib/cmdline: add new function get_option_ull() Wesley Zhao
2021-01-17 19:02 ` [PATCH v2 0/2] Make it possible to reserve memory on 64bit platform Dan Williams
@ 2021-01-18 10:42 ` Andy Shevchenko
2 siblings, 0 replies; 6+ messages in thread
From: Andy Shevchenko @ 2021-01-18 10:42 UTC (permalink / raw)
To: Wesley Zhao
Cc: akpm, keescook, tglx, kerneldev, nivedita, joe, gpiccoli, aquini,
gustavoars, ojeda, ndesaulniers, linux-kernel, david,
dan.j.williams, guohanjun, mchehab+huawei
On Sat, Jan 16, 2021 at 02:41:11AM -0800, Wesley Zhao wrote:
> I was trying to reserve some memory to save logs incase that Android panic or hang and then
> I can read the logs from QNX side from the memory reserved before on the Qualcomm 8155 hypervisor platform,
> and I find the "reserve=" parameter only support 32bit,so I made some change and send these patches.
Your series has disrupter in-reply-to change, can you fix your tools to have
all patches in one email thread?
> testcase:
> I test on the qemu with some cmdline like[qemu-system-x86_64 -kernel linux-next/arch/x86_64/boot/bzImage
> -hda ubuntu-system.ext4 -append "root=/dev/sda init=/bin/bash console=ttyS0 reserve=0x180000000,0x123456"
> -nographic] and check the /proc/iomem with 180000000-180123455 : reserved.
> And some other tests with the get_option with the parameter(-12345678) and so on
It's good but I was talking about unit test. Look into cmdline_kunit.c.
> Wesley Zhao (2):
> lib/cmdline: add new function get_option_ull()
> resource: Make it possible to reserve memory on 64bit platform
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread