Merge tag 'v4.1-rc5' into x86/mm, to refresh the tree before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 34a5b93..4afc05f 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -177,6 +177,7 @@
* look at pci_iomap().
*/
extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
+extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size,
unsigned long prot_val);
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index aeb4666e..2270e41 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -215,6 +215,44 @@
: [pax] "a" (p));
}
+/**
+ * pcommit_sfence() - persistent commit and fence
+ *
+ * The PCOMMIT instruction ensures that data that has been flushed from the
+ * processor's cache hierarchy with CLWB, CLFLUSHOPT or CLFLUSH is accepted to
+ * memory and is durable on the DIMM. The primary use case for this is
+ * persistent memory.
+ *
+ * This function shows how to properly use CLWB/CLFLUSHOPT/CLFLUSH and PCOMMIT
+ * with appropriate fencing.
+ *
+ * Example:
+ * void flush_and_commit_buffer(void *vaddr, unsigned int size)
+ * {
+ * unsigned long clflush_mask = boot_cpu_data.x86_clflush_size - 1;
+ * void *vend = vaddr + size;
+ * void *p;
+ *
+ * for (p = (void *)((unsigned long)vaddr & ~clflush_mask);
+ * p < vend; p += boot_cpu_data.x86_clflush_size)
+ * clwb(p);
+ *
+ * // SFENCE to order CLWB/CLFLUSHOPT/CLFLUSH cache flushes
+ * // MFENCE via mb() also works
+ * wmb();
+ *
+ * // PCOMMIT and the required SFENCE for ordering
+ * pcommit_sfence();
+ * }
+ *
+ * After this function completes the data pointed to by 'vaddr' has been
+ * accepted to memory and will be durable if the 'vaddr' points to persistent
+ * memory.
+ *
+ * PCOMMIT must always be ordered by an MFENCE or SFENCE, so to help simplify
+ * things we include both the PCOMMIT and the required SFENCE in the
+ * alternatives generated by pcommit_sfence().
+ */
static inline void pcommit_sfence(void)
{
alternative(ASM_NOP7,
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 7d74f7b..5b23967 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -137,7 +137,7 @@
idx = 1 * 8;
idx += ((start - 0x80000) >> 14);
return mtrr_state.fixed_ranges[idx];
- } else if (start < 0x1000000) {
+ } else {
idx = 3 * 8;
idx += ((start - 0xC0000) >> 12);
return mtrr_state.fixed_ranges[idx];
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 70e7444..a493bb8 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -237,7 +237,8 @@
* pat_enabled ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
*
* Till we fix all X drivers to use ioremap_wc(), we will use
- * UC MINUS.
+ * UC MINUS. Drivers that are certain they need or can already
+ * be converted over to strong UC can use ioremap_uc().
*/
enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;
@@ -247,6 +248,39 @@
EXPORT_SYMBOL(ioremap_nocache);
/**
+ * ioremap_uc - map bus memory into CPU space as strongly uncachable
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * ioremap_uc performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address.
+ *
+ * This version of ioremap ensures that the memory is marked with a strong
+ * preference as completely uncachable on the CPU when possible. For non-PAT
+ * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT
+ * systems this will set the PAT entry for the pages as strong UC. This call
+ * will honor existing caching rules from things like the PCI bus. Note that
+ * there are other caches and buffers on many busses. In particular driver
+ * authors should read up on PCI writes.
+ *
+ * It's useful if some control registers are in such an area and
+ * write combining or read caching is not desirable:
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
+{
+ enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;
+
+ return __ioremap_caller(phys_addr, size, pcm,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL_GPL(ioremap_uc);
+
+/**
* ioremap_wc - map memory into CPU space write combined
* @phys_addr: bus address of the memory
* @size: size of the resource to map
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 89af288..397838e 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -129,16 +129,15 @@
*/
void clflush_cache_range(void *vaddr, unsigned int size)
{
- void *vend = vaddr + size - 1;
+ unsigned long clflush_mask = boot_cpu_data.x86_clflush_size - 1;
+ void *vend = vaddr + size;
+ void *p;
mb();
- for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size)
- clflushopt(vaddr);
- /*
- * Flush any possible final partial cacheline:
- */
- clflushopt(vend);
+ for (p = (void *)((unsigned long)vaddr & ~clflush_mask);
+ p < vend; p += boot_cpu_data.x86_clflush_size)
+ clflushopt(p);
mb();
}
@@ -418,13 +417,11 @@
phys_addr_t phys_addr;
unsigned long offset;
enum pg_level level;
- unsigned long psize;
unsigned long pmask;
pte_t *pte;
pte = lookup_address(virt_addr, &level);
BUG_ON(!pte);
- psize = page_level_size(level);
pmask = page_level_mask(level);
offset = virt_addr & ~pmask;
phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
@@ -1468,6 +1465,9 @@
{
/*
* for now UC MINUS. see comments in ioremap_nocache()
+ * If you really need strong UC use ioremap_uc(), but note
+ * that you cannot override IO areas with set_memory_*() as
+ * these helpers cannot work with IO memory.
*/
return change_page_attr_set(&addr, numpages,
cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 9db0423..90ccba7 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -769,6 +769,14 @@
}
#endif
+#ifndef ioremap_uc
+#define ioremap_uc ioremap_uc
+static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size)
+{
+ return ioremap_nocache(offset, size);
+}
+#endif
+
#ifndef ioremap_wc
#define ioremap_wc ioremap_wc
static inline void __iomem *ioremap_wc(phys_addr_t offset, size_t size)