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-rw-r--r--arch/x86/Kconfig2
-rw-r--r--arch/x86/include/asm/mtrr.h7
-rw-r--r--arch/x86/include/uapi/asm/mtrr.h12
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c192
-rw-r--r--arch/x86/mm/pat.c4
-rw-r--r--arch/x86/mm/pgtable.c53
6 files changed, 181 insertions, 89 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index bd5ecb4de842..780cbe3834bc 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -100,7 +100,7 @@ config X86
select IRQ_FORCED_THREADING
select HAVE_BPF_JIT if X86_64
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
- select HAVE_ARCH_HUGE_VMAP if X86_64 || (X86_32 && X86_PAE)
+ select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
select ARCH_HAS_SG_CHAIN
select CLKEVT_I8253
select ARCH_HAVE_NMI_SAFE_CMPXCHG
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index f768f6298419..da8dff10f632 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -31,7 +31,7 @@
* arch_phys_wc_add and arch_phys_wc_del.
*/
# ifdef CONFIG_MTRR
-extern u8 mtrr_type_lookup(u64 addr, u64 end);
+extern u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform);
extern void mtrr_save_fixed_ranges(void *);
extern void mtrr_save_state(void);
extern int mtrr_add(unsigned long base, unsigned long size,
@@ -50,12 +50,13 @@ extern int mtrr_trim_uncached_memory(unsigned long end_pfn);
extern int amd_special_default_mtrr(void);
extern int phys_wc_to_mtrr_index(int handle);
# else
-static inline u8 mtrr_type_lookup(u64 addr, u64 end)
+static inline u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform)
{
/*
* Return no-MTRRs:
*/
- return 0xff;
+ *uniform = 1;
+ return MTRR_TYPE_INVALID;
}
#define mtrr_save_fixed_ranges(arg) do {} while (0)
#define mtrr_save_state() do {} while (0)
diff --git a/arch/x86/include/uapi/asm/mtrr.h b/arch/x86/include/uapi/asm/mtrr.h
index d0acb658c8f4..0bc86c6fcae0 100644
--- a/arch/x86/include/uapi/asm/mtrr.h
+++ b/arch/x86/include/uapi/asm/mtrr.h
@@ -88,6 +88,10 @@ struct mtrr_state_type {
mtrr_type def_type;
};
+/* Bit fields for enabled in struct mtrr_state_type */
+#define MTRR_STATE_MTRR_FIXED_ENABLED 0x01
+#define MTRR_STATE_MTRR_ENABLED 0x02
+
#define MTRRphysBase_MSR(reg) (0x200 + 2 * (reg))
#define MTRRphysMask_MSR(reg) (0x200 + 2 * (reg) + 1)
@@ -103,7 +107,7 @@ struct mtrr_state_type {
#define MTRRIOC_GET_PAGE_ENTRY _IOWR(MTRR_IOCTL_BASE, 8, struct mtrr_gentry)
#define MTRRIOC_KILL_PAGE_ENTRY _IOW(MTRR_IOCTL_BASE, 9, struct mtrr_sentry)
-/* These are the region types */
+/* MTRR memory types, which are defined in SDM */
#define MTRR_TYPE_UNCACHABLE 0
#define MTRR_TYPE_WRCOMB 1
/*#define MTRR_TYPE_ 2*/
@@ -113,5 +117,11 @@ struct mtrr_state_type {
#define MTRR_TYPE_WRBACK 6
#define MTRR_NUM_TYPES 7
+/*
+ * Invalid MTRR memory type. mtrr_type_lookup() returns this value when
+ * MTRRs are disabled. Note, this value is allocated from the reserved
+ * values (0x7-0xff) of the MTRR memory types.
+ */
+#define MTRR_TYPE_INVALID 0xff
#endif /* _UAPI_ASM_X86_MTRR_H */
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 7d74f7b3c6ba..a83f27a89cd3 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -102,59 +102,75 @@ static int check_type_overlap(u8 *prev, u8 *curr)
return 0;
}
-/*
- * Error/Semi-error returns:
- * 0xFF - when MTRR is not enabled
- * *repeat == 1 implies [start:end] spanned across MTRR range and type returned
- * corresponds only to [start:*partial_end].
- * Caller has to lookup again for [*partial_end:end].
+/**
+ * mtrr_type_lookup_fixed - look up memory type in MTRR fixed entries
+ *
+ * MTRR fixed entries are divided into the following ways:
+ * 0x00000 - 0x7FFFF : This range is divided into eight 64KB sub-ranges
+ * 0x80000 - 0xBFFFF : This range is divided into sixteen 16KB sub-ranges
+ * 0xC0000 - 0xFFFFF : This range is divided into sixty-four 4KB sub-ranges
+ *
+ * Return Values:
+ * MTRR_TYPE_(type) - Matched memory type
+ * MTRR_TYPE_INVALID - Unmatched or fixed entries are disabled
+ */
+static u8 mtrr_type_lookup_fixed(u64 start, u64 end)
+{
+ int idx;
+
+ if (start >= 0x100000)
+ return MTRR_TYPE_INVALID;
+
+ if (!(mtrr_state.have_fixed) ||
+ !(mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED))
+ return MTRR_TYPE_INVALID;
+
+ if (start < 0x80000) { /* 0x0 - 0x7FFFF */
+ idx = 0;
+ idx += (start >> 16);
+ return mtrr_state.fixed_ranges[idx];
+
+ } else if (start < 0xC0000) { /* 0x80000 - 0xBFFFF */
+ idx = 1 * 8;
+ idx += ((start - 0x80000) >> 14);
+ return mtrr_state.fixed_ranges[idx];
+ }
+
+ /* 0xC0000 - 0xFFFFF */
+ idx = 3 * 8;
+ idx += ((start - 0xC0000) >> 12);
+ return mtrr_state.fixed_ranges[idx];
+}
+
+/**
+ * mtrr_type_lookup_variable - look up memory type in MTRR variable entries
+ *
+ * Return Value:
+ * MTRR_TYPE_(type) - Matched memory type or default memory type (unmatched)
+ *
+ * Output Arguments:
+ * repeat - Set to 1 when [start:end] spanned across MTRR range and type
+ * returned corresponds only to [start:*partial_end]. Caller has
+ * to lookup again for [*partial_end:end].
+ * uniform - Set to 1 when MTRR covers the region uniformly, i.e. the region
+ * is fully covered by a single MTRR entry or the default type.
*/
-static u8 __mtrr_type_lookup(u64 start, u64 end, u64 *partial_end, int *repeat)
+static u8 mtrr_type_lookup_variable(u64 start, u64 end, u64 *partial_end,
+ int *repeat, u8 *uniform)
{
int i;
u64 base, mask;
u8 prev_match, curr_match;
*repeat = 0;
- if (!mtrr_state_set)
- return 0xFF;
-
- if (!mtrr_state.enabled)
- return 0xFF;
+ *uniform = 1;
/* Make end inclusive end, instead of exclusive */
end--;
- /* Look in fixed ranges. Just return the type as per start */
- if (mtrr_state.have_fixed && (start < 0x100000)) {
- int idx;
-
- if (start < 0x80000) {
- idx = 0;
- idx += (start >> 16);
- return mtrr_state.fixed_ranges[idx];
- } else if (start < 0xC0000) {
- idx = 1 * 8;
- idx += ((start - 0x80000) >> 14);
- return mtrr_state.fixed_ranges[idx];
- } else if (start < 0x1000000) {
- idx = 3 * 8;
- idx += ((start - 0xC0000) >> 12);
- return mtrr_state.fixed_ranges[idx];
- }
- }
-
- /*
- * Look in variable ranges
- * Look of multiple ranges matching this address and pick type
- * as per MTRR precedence
- */
- if (!(mtrr_state.enabled & 2))
- return mtrr_state.def_type;
-
- prev_match = 0xFF;
+ prev_match = MTRR_TYPE_INVALID;
for (i = 0; i < num_var_ranges; ++i) {
- unsigned short start_state, end_state;
+ unsigned short start_state, end_state, inclusive;
if (!(mtrr_state.var_ranges[i].mask_lo & (1 << 11)))
continue;
@@ -166,20 +182,22 @@ static u8 __mtrr_type_lookup(u64 start, u64 end, u64 *partial_end, int *repeat)
start_state = ((start & mask) == (base & mask));
end_state = ((end & mask) == (base & mask));
+ inclusive = ((start < base) && (end > base));
- if (start_state != end_state) {
+ if ((start_state != end_state) || inclusive) {
/*
* We have start:end spanning across an MTRR.
- * We split the region into
- * either
- * (start:mtrr_end) (mtrr_end:end)
- * or
- * (start:mtrr_start) (mtrr_start:end)
+ * We split the region into either
+ * - start_state:1
+ * (start:mtrr_end) (mtrr_end:end)
+ * - end_state:1 or inclusive:1
+ * (start:mtrr_start) (mtrr_start:end)
* depending on kind of overlap.
* Return the type for first region and a pointer to
* the start of second region so that caller will
* lookup again on the second region.
- * Note: This way we handle multiple overlaps as well.
+ * Note: This way we handle overlaps with multiple
+ * entries and the default type properly.
*/
if (start_state)
*partial_end = base + get_mtrr_size(mask);
@@ -193,59 +211,95 @@ static u8 __mtrr_type_lookup(u64 start, u64 end, u64 *partial_end, int *repeat)
end = *partial_end - 1; /* end is inclusive */
*repeat = 1;
+ *uniform = 0;
}
- if ((start & mask) != (base & mask))
+ if (!start_state)
continue;
curr_match = mtrr_state.var_ranges[i].base_lo & 0xff;
- if (prev_match == 0xFF) {
+ if (prev_match == MTRR_TYPE_INVALID) {
prev_match = curr_match;
continue;
}
+ *uniform = 0;
if (check_type_overlap(&prev_match, &curr_match))
return curr_match;
}
- if (mtrr_tom2) {
- if (start >= (1ULL<<32) && (end < mtrr_tom2))
- return MTRR_TYPE_WRBACK;
- }
-
- if (prev_match != 0xFF)
+ if (prev_match != MTRR_TYPE_INVALID)
return prev_match;
return mtrr_state.def_type;
}
-/*
- * Returns the effective MTRR type for the region
- * Error return:
- * 0xFF - when MTRR is not enabled
+/**
+ * mtrr_type_lookup - look up memory type in MTRR
+ *
+ * Return Values:
+ * MTRR_TYPE_(type) - The effective MTRR type for the region
+ * MTRR_TYPE_INVALID - MTRR is disabled
+ *
+ * Output Argument:
+ * uniform - Set to 1 when MTRR covers the region uniformly, i.e. the region
+ * is fully covered by a single MTRR entry or the default type.
*/
-u8 mtrr_type_lookup(u64 start, u64 end)
+u8 mtrr_type_lookup(u64 start, u64 end, u8 *uniform)
{
- u8 type, prev_type;
+ u8 type, prev_type, is_uniform, dummy;
int repeat;
u64 partial_end;
- type = __mtrr_type_lookup(start, end, &partial_end, &repeat);
+ *uniform = 1;
+
+ if (!mtrr_state_set)
+ return MTRR_TYPE_INVALID;
+
+ if (!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED))
+ return MTRR_TYPE_INVALID;
+
+ /*
+ * Look up the fixed ranges first, which take priority over
+ * the variable ranges.
+ */
+ type = mtrr_type_lookup_fixed(start, end);
+ if (type != MTRR_TYPE_INVALID) {
+ *uniform = 0;
+ return type;
+ }
+
+ /*
+ * Look up the variable ranges. Look of multiple ranges matching
+ * this address and pick type as per MTRR precedence.
+ */
+ type = mtrr_type_lookup_variable(start, end, &partial_end,
+ &repeat, &is_uniform);
/*
* Common path is with repeat = 0.
* However, we can have cases where [start:end] spans across some
- * MTRR range. Do repeated lookups for that case here.
+ * MTRR ranges and/or the default type. Do repeated lookups for
+ * that case here.
*/
while (repeat) {
prev_type = type;
start = partial_end;
- type = __mtrr_type_lookup(start, end, &partial_end, &repeat);
+ is_uniform = 0;
+
+ type = mtrr_type_lookup_variable(start, end, &partial_end,
+ &repeat, &dummy);
- if (check_type_overlap(&prev_type, &type))
+ if (check_type_overlap(&prev_type, &type)) {
+ *uniform = 0;
return type;
+ }
}
+ if (mtrr_tom2 && (start >= (1ULL<<32)) && (end < mtrr_tom2))
+ return MTRR_TYPE_WRBACK;
+
+ *uniform = is_uniform;
return type;
}
@@ -347,7 +401,9 @@ static void __init print_mtrr_state(void)
mtrr_attrib_to_str(mtrr_state.def_type));
if (mtrr_state.have_fixed) {
pr_debug("MTRR fixed ranges %sabled:\n",
- mtrr_state.enabled & 1 ? "en" : "dis");
+ ((mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
+ (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) ?
+ "en" : "dis");
print_fixed(0x00000, 0x10000, mtrr_state.fixed_ranges + 0);
for (i = 0; i < 2; ++i)
print_fixed(0x80000 + i * 0x20000, 0x04000,
@@ -360,7 +416,7 @@ static void __init print_mtrr_state(void)
print_fixed_last();
}
pr_debug("MTRR variable ranges %sabled:\n",
- mtrr_state.enabled & 2 ? "en" : "dis");
+ mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED ? "en" : "dis");
high_width = (__ffs64(size_or_mask) - (32 - PAGE_SHIFT) + 3) / 4;
for (i = 0; i < num_var_ranges; ++i) {
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 35af6771a95a..372ad422c2c3 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -267,9 +267,9 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end,
* request is for WB.
*/
if (req_type == _PAGE_CACHE_MODE_WB) {
- u8 mtrr_type;
+ u8 mtrr_type, uniform;
- mtrr_type = mtrr_type_lookup(start, end);
+ mtrr_type = mtrr_type_lookup(start, end, &uniform);
if (mtrr_type != MTRR_TYPE_WRBACK)
return _PAGE_CACHE_MODE_UC_MINUS;
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 0b97d2c75df3..3d6edea8087e 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -563,16 +563,22 @@ void native_set_fixmap(enum fixed_addresses idx, phys_addr_t phys,
}
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+/**
+ * pud_set_huge - setup kernel PUD mapping
+ *
+ * MTRR can override PAT memory types with 4KB granularity. Therefore,
+ * it only sets up a huge page when the range is mapped uniformly by MTRR
+ * (i.e. the range is fully covered by a single MTRR entry or the default
+ * type) or the MTRR memory type is WB.
+ *
+ * Return 1 on success, and 0 when no PUD was set.
+ */
int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
{
- u8 mtrr;
+ u8 mtrr, uniform;
- /*
- * Do not use a huge page when the range is covered by non-WB type
- * of MTRRs.
- */
- mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE);
- if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF))
+ mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE, &uniform);
+ if ((!uniform) && (mtrr != MTRR_TYPE_WRBACK))
return 0;
prot = pgprot_4k_2_large(prot);
@@ -584,17 +590,26 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
return 1;
}
+/**
+ * pmd_set_huge - setup kernel PMD mapping
+ *
+ * MTRR can override PAT memory types with 4KB granularity. Therefore,
+ * it only sets up a huge page when the range is mapped uniformly by MTRR
+ * (i.e. the range is fully covered by a single MTRR entry or the default
+ * type) or the MTRR memory type is WB.
+ *
+ * Return 1 on success, and 0 when no PMD was set.
+ */
int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
{
- u8 mtrr;
+ u8 mtrr, uniform;
- /*
- * Do not use a huge page when the range is covered by non-WB type
- * of MTRRs.
- */
- mtrr = mtrr_type_lookup(addr, addr + PMD_SIZE);
- if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF))
+ mtrr = mtrr_type_lookup(addr, addr + PMD_SIZE, &uniform);
+ if ((!uniform) && (mtrr != MTRR_TYPE_WRBACK)) {
+ pr_warn("pmd_set_huge: requesting [mem %#010llx-%#010llx], which spans more than a single MTRR entry\n",
+ addr, addr + PMD_SIZE);
return 0;
+ }
prot = pgprot_4k_2_large(prot);
@@ -605,6 +620,11 @@ int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
return 1;
}
+/**
+ * pud_clear_huge - clear kernel PUD mapping when it is set
+ *
+ * Return 1 on success, and 0 when no PUD map was found.
+ */
int pud_clear_huge(pud_t *pud)
{
if (pud_large(*pud)) {
@@ -615,6 +635,11 @@ int pud_clear_huge(pud_t *pud)
return 0;
}
+/**
+ * pmd_clear_huge - clear kernel PMD mapping when it is set
+ *
+ * Return 1 on success, and 0 when no PMD map was found.
+ */
int pmd_clear_huge(pmd_t *pmd)
{
if (pmd_large(*pmd)) {