| Message ID | 20170216154430.19244.95519.stgit@tlendack-t1.amdoffice.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Feb 16, 2017 at 09:44:30AM -0600, Tom Lendacky wrote: > This patch adds support to return the E820 type associated with an address s/This patch adds/Add/ > range. > > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> > --- > arch/x86/include/asm/e820/api.h | 2 ++ > arch/x86/include/asm/e820/types.h | 2 ++ > arch/x86/kernel/e820.c | 26 +++++++++++++++++++++++--- > 3 files changed, 27 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h > index 8e0f8b8..7c1bdc9 100644 > --- a/arch/x86/include/asm/e820/api.h > +++ b/arch/x86/include/asm/e820/api.h > @@ -38,6 +38,8 @@ > extern void e820__reallocate_tables(void); > extern void e820__register_nosave_regions(unsigned long limit_pfn); > > +extern enum e820_type e820__get_entry_type(u64 start, u64 end); > + > /* > * Returns true iff the specified range [start,end) is completely contained inside > * the ISA region. > diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h > index 4adeed0..bf49591 100644 > --- a/arch/x86/include/asm/e820/types.h > +++ b/arch/x86/include/asm/e820/types.h > @@ -7,6 +7,8 @@ > * These are the E820 types known to the kernel: > */ > enum e820_type { > + E820_TYPE_INVALID = 0, > + Now this is strange - ACPI spec doesn't explicitly say that range type 0 is invalid. Am I looking at the wrong place? "Table 15-312 Address Range Types12" in ACPI spec 6. If 0 is really the invalid entry, then e820_print_type() needs updating too. And then the invalid-entry-add should be a separate patch. > E820_TYPE_RAM = 1, > E820_TYPE_RESERVED = 2, > E820_TYPE_ACPI = 3,
On 2/20/2017 2:09 PM, Borislav Petkov wrote: > On Thu, Feb 16, 2017 at 09:44:30AM -0600, Tom Lendacky wrote: >> This patch adds support to return the E820 type associated with an address > > s/This patch adds/Add/ > >> range. >> >> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> >> --- >> arch/x86/include/asm/e820/api.h | 2 ++ >> arch/x86/include/asm/e820/types.h | 2 ++ >> arch/x86/kernel/e820.c | 26 +++++++++++++++++++++++--- >> 3 files changed, 27 insertions(+), 3 deletions(-) >> >> diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h >> index 8e0f8b8..7c1bdc9 100644 >> --- a/arch/x86/include/asm/e820/api.h >> +++ b/arch/x86/include/asm/e820/api.h >> @@ -38,6 +38,8 @@ >> extern void e820__reallocate_tables(void); >> extern void e820__register_nosave_regions(unsigned long limit_pfn); >> >> +extern enum e820_type e820__get_entry_type(u64 start, u64 end); >> + >> /* >> * Returns true iff the specified range [start,end) is completely contained inside >> * the ISA region. >> diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h >> index 4adeed0..bf49591 100644 >> --- a/arch/x86/include/asm/e820/types.h >> +++ b/arch/x86/include/asm/e820/types.h >> @@ -7,6 +7,8 @@ >> * These are the E820 types known to the kernel: >> */ >> enum e820_type { >> + E820_TYPE_INVALID = 0, >> + > > Now this is strange - ACPI spec doesn't explicitly say that range type 0 > is invalid. Am I looking at the wrong place? > > "Table 15-312 Address Range Types12" in ACPI spec 6. > > If 0 is really the invalid entry, then e820_print_type() needs updating > too. And then the invalid-entry-add should be a separate patch. The 0 return (originally) was to indicate that an e820 entry for the range wasn't found. This series just gave it a name. So it's not that the type field held a 0. Since 0 isn't defined in the ACPI spec I don't see an issue with creating it and I can add a comment to the effect that this value is used for the type when an e820 entry isn't found. I could always rename it to E820_TYPE_NOT_FOUND if that would help. Or if we want to guard against ACPI adding a type 0 in the future, I could make the function return an int and then return -EINVAL if an e820 entry isn't found. This might be the better option. Thanks, Tom > >> E820_TYPE_RAM = 1, >> E820_TYPE_RESERVED = 2, >> E820_TYPE_ACPI = 3, >
On Tue, Feb 28, 2017 at 04:34:39PM -0600, Tom Lendacky wrote: > Or if we want to guard against ACPI adding a type 0 in the future, I > could make the function return an int and then return -EINVAL if an e820 > entry isn't found. This might be the better option. Yap, think so too. I don't trust specs anyway :)
diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h index 8e0f8b8..7c1bdc9 100644 --- a/arch/x86/include/asm/e820/api.h +++ b/arch/x86/include/asm/e820/api.h @@ -38,6 +38,8 @@ extern void e820__reallocate_tables(void); extern void e820__register_nosave_regions(unsigned long limit_pfn); +extern enum e820_type e820__get_entry_type(u64 start, u64 end); + /* * Returns true iff the specified range [start,end) is completely contained inside * the ISA region. diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h index 4adeed0..bf49591 100644 --- a/arch/x86/include/asm/e820/types.h +++ b/arch/x86/include/asm/e820/types.h @@ -7,6 +7,8 @@ * These are the E820 types known to the kernel: */ enum e820_type { + E820_TYPE_INVALID = 0, + E820_TYPE_RAM = 1, E820_TYPE_RESERVED = 2, E820_TYPE_ACPI = 3, diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 6e9b26f..2ee7ee2 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -84,7 +84,8 @@ bool e820__mapped_any(u64 start, u64 end, enum e820_type type) * Note: this function only works correctly once the E820 table is sorted and * not-overlapping (at least for the range specified), which is the case normally. */ -bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type) +static struct e820_entry *__e820__mapped_all(u64 start, u64 end, + enum e820_type type) { int i; @@ -110,9 +111,28 @@ bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type) * coverage of the desired range exists: */ if (start >= end) - return 1; + return entry; } - return 0; + + return NULL; +} + +/* + * This function checks if the entire range <start,end> is mapped with type. + */ +bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type) +{ + return __e820__mapped_all(start, end, type) ? 1 : 0; +} + +/* + * This function returns the type associated with the range <start,end>. + */ +enum e820_type e820__get_entry_type(u64 start, u64 end) +{ + struct e820_entry *entry = __e820__mapped_all(start, end, 0); + + return entry ? entry->type : E820_TYPE_INVALID; } /*
This patch adds support to return the E820 type associated with an address range. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> --- arch/x86/include/asm/e820/api.h | 2 ++ arch/x86/include/asm/e820/types.h | 2 ++ arch/x86/kernel/e820.c | 26 +++++++++++++++++++++++--- 3 files changed, 27 insertions(+), 3 deletions(-)