* [PATCH] x86: e820: Implement a range manipulation operator
@ 2018-02-01 23:13 Jan H. Schönherr
2018-02-02 20:50 ` Andy Shevchenko
0 siblings, 1 reply; 4+ messages in thread
From: Jan H. Schönherr @ 2018-02-01 23:13 UTC (permalink / raw)
To: Ingo Molnar, Thomas Gleixner, x86
Cc: Jan H. Schönherr, H. Peter Anvin, linux-kernel
Add a more versatile memmap= operator, which -- in addition to all the
things that were possible before -- allows you to:
- redeclare existing ranges -- before, you were limited to adding ranges;
- drop any range -- like a mem= for any location;
- use any e820 memory type -- not just some predefined ones.
The syntax is:
memmap=<size>%<offset>-<oldtype>+<newtype>
Size and offset work as usual. The "-<oldtype>" and "+<newtype>" are
optional and their existence determine the behavior: The command
works on the specified range of memory limited to type <oldtype>
(if specified). This memory is then configured to show up as <newtype>.
If <newtype> is not specified, the memory is removed from the e820 map.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
---
Documentation/admin-guide/kernel-parameters.txt | 9 +++++++++
arch/x86/kernel/e820.c | 18 ++++++++++++++++++
2 files changed, 27 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 46b26bfee27b..94609eaff2a9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2221,6 +2221,15 @@
The memory region may be marked as e820 type 12 (0xc)
and is NVDIMM or ADR memory.
+ memmap=<size>%<offset>-<oldtype>+<newtype>
+ [KNL,ACPI] Convert memory within the specified region
+ from <oldtype> to <newtype>. If "-<oldtype>" is left
+ out, the whole region will be marked as <newtype>,
+ even if previously unavailable. If "+<newtype>" is left
+ out, matching memory will be removed. Types are
+ specified as e820 types, eg, 1==RAM, 2==reserved,
+ 3==ACPI, 12==PRAM.
+
memory_corruption_check=0/1 [X86]
Some BIOSes seem to corrupt the first 64k of
memory when doing things like suspend/resume.
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 71c11ad5643e..cd22c6a07632 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -924,6 +924,24 @@ static int __init parse_memmap_one(char *p)
} else if (*p == '!') {
start_at = memparse(p+1, &p);
e820__range_add(start_at, mem_size, E820_TYPE_PRAM);
+ } else if (*p == '%') {
+ enum e820_type from = 0, to = 0;
+
+ start_at = memparse(p + 1, &p);
+ if (*p == '-')
+ from = simple_strtoull(p + 1, &p, 0);
+ if (*p == '+')
+ to = simple_strtoull(p + 1, &p, 0);
+ if (*p != 0)
+ return -EINVAL;
+ if (from && to)
+ e820__range_update(start_at, mem_size, from, to);
+ else if (to)
+ e820__range_add(start_at, mem_size, to);
+ else if (from)
+ e820__range_remove(start_at, mem_size, from, 1);
+ else
+ e820__range_remove(start_at, mem_size, 0, 0);
} else {
e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
}
--
2.9.3.1.gcba166c.dirty
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] x86: e820: Implement a range manipulation operator
2018-02-01 23:13 [PATCH] x86: e820: Implement a range manipulation operator Jan H. Schönherr
@ 2018-02-02 20:50 ` Andy Shevchenko
2018-02-02 23:06 ` Jan H. Schönherr
0 siblings, 1 reply; 4+ messages in thread
From: Andy Shevchenko @ 2018-02-02 20:50 UTC (permalink / raw)
To: Jan H. Schönherr
Cc: Ingo Molnar, Thomas Gleixner, x86, H. Peter Anvin,
Linux Kernel Mailing List
On Fri, Feb 2, 2018 at 1:13 AM, Jan H. Schönherr <jschoenh@amazon.de> wrote:
> + [KNL,ACPI] Convert memory within the specified region
> + from <oldtype> to <newtype>. If "-<oldtype>" is left
> + out, the whole region will be marked as <newtype>,
> + even if previously unavailable. If "+<newtype>" is left
> + out, matching memory will be removed. Types are
> + specified as e820 types, eg, 1==RAM, 2==reserved,
> + 3==ACPI, 12==PRAM.
s/==/ = /g
> + } else if (*p == '%') {
> + enum e820_type from = 0, to = 0;
> +
> + start_at = memparse(p + 1, &p);
> + if (*p == '-')
> + from = simple_strtoull(p + 1, &p, 0);
> + if (*p == '+')
> + to = simple_strtoull(p + 1, &p, 0);
> + if (*p != 0)
if (*p)
or
if (*p != '\0')
?
> + return -EINVAL;
> + if (from && to)
> + e820__range_update(start_at, mem_size, from, to);
> + else if (to)
> + e820__range_add(start_at, mem_size, to);
> + else if (from)
> + e820__range_remove(start_at, mem_size, from, 1);
> + else
> + e820__range_remove(start_at, mem_size, 0, 0);
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] x86: e820: Implement a range manipulation operator
2018-02-02 20:50 ` Andy Shevchenko
@ 2018-02-02 23:06 ` Jan H. Schönherr
2018-02-02 23:10 ` [PATCH v2] " Jan H. Schönherr
0 siblings, 1 reply; 4+ messages in thread
From: Jan H. Schönherr @ 2018-02-02 23:06 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Ingo Molnar, Thomas Gleixner, x86, H. Peter Anvin,
Linux Kernel Mailing List
On 02/02/2018 09:50 PM, Andy Shevchenko wrote:
> On Fri, Feb 2, 2018 at 1:13 AM, Jan H. Schönherr <jschoenh@amazon.de> wrote:
>
>> + [KNL,ACPI] Convert memory within the specified region
>> + from <oldtype> to <newtype>. If "-<oldtype>" is left
>> + out, the whole region will be marked as <newtype>,
>> + even if previously unavailable. If "+<newtype>" is left
>> + out, matching memory will be removed. Types are
>> + specified as e820 types, eg, 1==RAM, 2==reserved,
>> + 3==ACPI, 12==PRAM.
>
> s/==/ = /g
Sure. I've also properly abbreviated that "e.g.".
>> + } else if (*p == '%') {
>> + enum e820_type from = 0, to = 0;
>> +
>> + start_at = memparse(p + 1, &p);
>> + if (*p == '-')
>> + from = simple_strtoull(p + 1, &p, 0);
>> + if (*p == '+')
>> + to = simple_strtoull(p + 1, &p, 0);
>> + if (*p != 0)
>
> if (*p)
>
> or
>
> if (*p != '\0')
>
> ?
Something similar to the latter is used in the function already. The latter it is.
Regards
Jan
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v2] x86: e820: Implement a range manipulation operator
2018-02-02 23:06 ` Jan H. Schönherr
@ 2018-02-02 23:10 ` Jan H. Schönherr
0 siblings, 0 replies; 4+ messages in thread
From: Jan H. Schönherr @ 2018-02-02 23:10 UTC (permalink / raw)
To: Ingo Molnar, Thomas Gleixner, x86
Cc: Jan H. Schönherr, Andy Shevchenko, H. Peter Anvin, linux-kernel
Add a more versatile memmap= operator, which -- in addition to all the
things that were possible before -- allows you to:
- redeclare existing ranges -- before, you were limited to adding ranges;
- drop any range -- like a mem= for any location;
- use any e820 memory type -- not just some predefined ones.
The syntax is:
memmap=<size>%<offset>-<oldtype>+<newtype>
Size and offset work as usual. The "-<oldtype>" and "+<newtype>" are
optional and their existence determine the behavior: The command
works on the specified range of memory limited to type <oldtype>
(if specified). This memory is then configured to show up as <newtype>.
If <newtype> is not specified, the memory is removed from the e820 map.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
---
v2: Small coding style and typography adjustments
Documentation/admin-guide/kernel-parameters.txt | 9 +++++++++
arch/x86/kernel/e820.c | 18 ++++++++++++++++++
2 files changed, 27 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 46b26bfee27b..60926ae3ec06 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2221,6 +2221,15 @@
The memory region may be marked as e820 type 12 (0xc)
and is NVDIMM or ADR memory.
+ memmap=<size>%<offset>-<oldtype>+<newtype>
+ [KNL,ACPI] Convert memory within the specified region
+ from <oldtype> to <newtype>. If "-<oldtype>" is left
+ out, the whole region will be marked as <newtype>,
+ even if previously unavailable. If "+<newtype>" is left
+ out, matching memory will be removed. Types are
+ specified as e820 types, e.g., 1 = RAM, 2 = reserved,
+ 3 = ACPI, 12 = PRAM.
+
memory_corruption_check=0/1 [X86]
Some BIOSes seem to corrupt the first 64k of
memory when doing things like suspend/resume.
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 71c11ad5643e..6a2cb1442e05 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -924,6 +924,24 @@ static int __init parse_memmap_one(char *p)
} else if (*p == '!') {
start_at = memparse(p+1, &p);
e820__range_add(start_at, mem_size, E820_TYPE_PRAM);
+ } else if (*p == '%') {
+ enum e820_type from = 0, to = 0;
+
+ start_at = memparse(p + 1, &p);
+ if (*p == '-')
+ from = simple_strtoull(p + 1, &p, 0);
+ if (*p == '+')
+ to = simple_strtoull(p + 1, &p, 0);
+ if (*p != '\0')
+ return -EINVAL;
+ if (from && to)
+ e820__range_update(start_at, mem_size, from, to);
+ else if (to)
+ e820__range_add(start_at, mem_size, to);
+ else if (from)
+ e820__range_remove(start_at, mem_size, from, 1);
+ else
+ e820__range_remove(start_at, mem_size, 0, 0);
} else {
e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
}
--
2.9.3.1.gcba166c.dirty
^ permalink raw reply related [flat|nested] 4+ messages in thread
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2018-02-01 23:13 [PATCH] x86: e820: Implement a range manipulation operator Jan H. Schönherr
2018-02-02 20:50 ` Andy Shevchenko
2018-02-02 23:06 ` Jan H. Schönherr
2018-02-02 23:10 ` [PATCH v2] " Jan H. Schönherr
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