922 lines
23 KiB
C
922 lines
23 KiB
C
/*
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* Handle caching attributes in page tables (PAT)
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*
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* Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
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* Suresh B Siddha <suresh.b.siddha@intel.com>
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*
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* Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
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*/
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#include <linux/seq_file.h>
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#include <linux/bootmem.h>
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#include <linux/debugfs.h>
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#include <linux/kernel.h>
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#include <linux/gfp.h>
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#include <linux/mm.h>
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#include <linux/fs.h>
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#include <asm/cacheflush.h>
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#include <asm/processor.h>
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#include <asm/tlbflush.h>
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#include <asm/pgtable.h>
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#include <asm/fcntl.h>
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#include <asm/e820.h>
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#include <asm/mtrr.h>
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#include <asm/page.h>
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#include <asm/msr.h>
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#include <asm/pat.h>
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#include <asm/io.h>
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#ifdef CONFIG_X86_PAT
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int __read_mostly pat_enabled = 1;
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void __cpuinit pat_disable(char *reason)
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{
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pat_enabled = 0;
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printk(KERN_INFO "%s\n", reason);
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}
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static int __init nopat(char *str)
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{
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pat_disable("PAT support disabled.");
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return 0;
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}
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early_param("nopat", nopat);
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#endif
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static int debug_enable;
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static int __init pat_debug_setup(char *str)
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{
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debug_enable = 1;
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return 0;
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}
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__setup("debugpat", pat_debug_setup);
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#define dprintk(fmt, arg...) \
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do { if (debug_enable) printk(KERN_INFO fmt, ##arg); } while (0)
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static u64 __read_mostly boot_pat_state;
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enum {
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PAT_UC = 0, /* uncached */
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PAT_WC = 1, /* Write combining */
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PAT_WT = 4, /* Write Through */
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PAT_WP = 5, /* Write Protected */
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PAT_WB = 6, /* Write Back (default) */
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PAT_UC_MINUS = 7, /* UC, but can be overriden by MTRR */
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};
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#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
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void pat_init(void)
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{
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u64 pat;
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if (!pat_enabled)
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return;
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/* Paranoia check. */
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if (!cpu_has_pat && boot_pat_state) {
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/*
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* If this happens we are on a secondary CPU, but
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* switched to PAT on the boot CPU. We have no way to
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* undo PAT.
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*/
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printk(KERN_ERR "PAT enabled, "
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"but not supported by secondary CPU\n");
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BUG();
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}
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/* Set PWT to Write-Combining. All other bits stay the same */
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/*
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* PTE encoding used in Linux:
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* PAT
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* |PCD
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* ||PWT
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* |||
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* 000 WB _PAGE_CACHE_WB
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* 001 WC _PAGE_CACHE_WC
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* 010 UC- _PAGE_CACHE_UC_MINUS
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* 011 UC _PAGE_CACHE_UC
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* PAT bit unused
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*/
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pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
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PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
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/* Boot CPU check */
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if (!boot_pat_state)
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rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
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wrmsrl(MSR_IA32_CR_PAT, pat);
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printk(KERN_INFO "x86 PAT enabled: cpu %d, old 0x%Lx, new 0x%Lx\n",
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smp_processor_id(), boot_pat_state, pat);
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}
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#undef PAT
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static char *cattr_name(unsigned long flags)
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{
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switch (flags & _PAGE_CACHE_MASK) {
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case _PAGE_CACHE_UC: return "uncached";
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case _PAGE_CACHE_UC_MINUS: return "uncached-minus";
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case _PAGE_CACHE_WB: return "write-back";
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case _PAGE_CACHE_WC: return "write-combining";
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default: return "broken";
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}
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}
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/*
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* The global memtype list keeps track of memory type for specific
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* physical memory areas. Conflicting memory types in different
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* mappings can cause CPU cache corruption. To avoid this we keep track.
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*
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* The list is sorted based on starting address and can contain multiple
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* entries for each address (this allows reference counting for overlapping
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* areas). All the aliases have the same cache attributes of course.
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* Zero attributes are represented as holes.
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*
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* Currently the data structure is a list because the number of mappings
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* are expected to be relatively small. If this should be a problem
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* it could be changed to a rbtree or similar.
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*
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* memtype_lock protects the whole list.
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*/
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struct memtype {
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u64 start;
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u64 end;
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unsigned long type;
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struct list_head nd;
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};
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static LIST_HEAD(memtype_list);
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static DEFINE_SPINLOCK(memtype_lock); /* protects memtype list */
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/*
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* Does intersection of PAT memory type and MTRR memory type and returns
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* the resulting memory type as PAT understands it.
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* (Type in pat and mtrr will not have same value)
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* The intersection is based on "Effective Memory Type" tables in IA-32
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* SDM vol 3a
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*/
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static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
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{
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/*
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* Look for MTRR hint to get the effective type in case where PAT
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* request is for WB.
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*/
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if (req_type == _PAGE_CACHE_WB) {
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u8 mtrr_type;
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mtrr_type = mtrr_type_lookup(start, end);
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if (mtrr_type == MTRR_TYPE_UNCACHABLE)
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return _PAGE_CACHE_UC;
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if (mtrr_type == MTRR_TYPE_WRCOMB)
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return _PAGE_CACHE_WC;
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}
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return req_type;
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}
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static int
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chk_conflict(struct memtype *new, struct memtype *entry, unsigned long *type)
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{
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if (new->type != entry->type) {
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if (type) {
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new->type = entry->type;
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*type = entry->type;
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} else
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goto conflict;
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}
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/* check overlaps with more than one entry in the list */
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list_for_each_entry_continue(entry, &memtype_list, nd) {
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if (new->end <= entry->start)
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break;
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else if (new->type != entry->type)
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goto conflict;
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}
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return 0;
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conflict:
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printk(KERN_INFO "%s:%d conflicting memory types "
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"%Lx-%Lx %s<->%s\n", current->comm, current->pid, new->start,
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new->end, cattr_name(new->type), cattr_name(entry->type));
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return -EBUSY;
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}
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static struct memtype *cached_entry;
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static u64 cached_start;
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/*
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* For RAM pages, mark the pages as non WB memory type using
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* PageNonWB (PG_arch_1). We allow only one set_memory_uc() or
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* set_memory_wc() on a RAM page at a time before marking it as WB again.
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* This is ok, because only one driver will be owning the page and
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* doing set_memory_*() calls.
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*
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* For now, we use PageNonWB to track that the RAM page is being mapped
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* as non WB. In future, we will have to use one more flag
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* (or some other mechanism in page_struct) to distinguish between
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* UC and WC mapping.
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*/
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static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type,
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unsigned long *new_type)
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{
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struct page *page;
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u64 pfn, end_pfn;
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for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
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page = pfn_to_page(pfn);
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if (page_mapped(page) || PageNonWB(page))
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goto out;
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SetPageNonWB(page);
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}
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return 0;
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out:
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end_pfn = pfn;
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for (pfn = (start >> PAGE_SHIFT); pfn < end_pfn; ++pfn) {
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page = pfn_to_page(pfn);
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ClearPageNonWB(page);
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}
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return -EINVAL;
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}
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static int free_ram_pages_type(u64 start, u64 end)
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{
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struct page *page;
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u64 pfn, end_pfn;
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for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
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page = pfn_to_page(pfn);
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if (page_mapped(page) || !PageNonWB(page))
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goto out;
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ClearPageNonWB(page);
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}
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return 0;
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out:
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end_pfn = pfn;
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for (pfn = (start >> PAGE_SHIFT); pfn < end_pfn; ++pfn) {
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page = pfn_to_page(pfn);
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SetPageNonWB(page);
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}
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return -EINVAL;
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}
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/*
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* req_type typically has one of the:
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* - _PAGE_CACHE_WB
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* - _PAGE_CACHE_WC
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* - _PAGE_CACHE_UC_MINUS
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* - _PAGE_CACHE_UC
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*
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* req_type will have a special case value '-1', when requester want to inherit
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* the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
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*
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* If new_type is NULL, function will return an error if it cannot reserve the
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* region with req_type. If new_type is non-NULL, function will return
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* available type in new_type in case of no error. In case of any error
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* it will return a negative return value.
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*/
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int reserve_memtype(u64 start, u64 end, unsigned long req_type,
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unsigned long *new_type)
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{
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struct memtype *new, *entry;
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unsigned long actual_type;
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struct list_head *where;
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int is_range_ram;
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int err = 0;
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BUG_ON(start >= end); /* end is exclusive */
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if (!pat_enabled) {
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/* This is identical to page table setting without PAT */
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if (new_type) {
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if (req_type == -1)
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*new_type = _PAGE_CACHE_WB;
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else
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*new_type = req_type & _PAGE_CACHE_MASK;
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}
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return 0;
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}
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/* Low ISA region is always mapped WB in page table. No need to track */
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if (is_ISA_range(start, end - 1)) {
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if (new_type)
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*new_type = _PAGE_CACHE_WB;
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return 0;
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}
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if (req_type == -1) {
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/*
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* Call mtrr_lookup to get the type hint. This is an
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* optimization for /dev/mem mmap'ers into WB memory (BIOS
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* tools and ACPI tools). Use WB request for WB memory and use
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* UC_MINUS otherwise.
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*/
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u8 mtrr_type = mtrr_type_lookup(start, end);
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if (mtrr_type == MTRR_TYPE_WRBACK)
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actual_type = _PAGE_CACHE_WB;
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else
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actual_type = _PAGE_CACHE_UC_MINUS;
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} else {
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actual_type = pat_x_mtrr_type(start, end,
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req_type & _PAGE_CACHE_MASK);
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}
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is_range_ram = pagerange_is_ram(start, end);
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if (is_range_ram == 1)
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return reserve_ram_pages_type(start, end, req_type, new_type);
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else if (is_range_ram < 0)
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return -EINVAL;
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new = kmalloc(sizeof(struct memtype), GFP_KERNEL);
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if (!new)
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return -ENOMEM;
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new->start = start;
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new->end = end;
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new->type = actual_type;
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if (new_type)
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*new_type = actual_type;
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spin_lock(&memtype_lock);
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if (cached_entry && start >= cached_start)
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entry = cached_entry;
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else
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entry = list_entry(&memtype_list, struct memtype, nd);
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/* Search for existing mapping that overlaps the current range */
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where = NULL;
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list_for_each_entry_continue(entry, &memtype_list, nd) {
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if (end <= entry->start) {
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where = entry->nd.prev;
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cached_entry = list_entry(where, struct memtype, nd);
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break;
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} else if (start <= entry->start) { /* end > entry->start */
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err = chk_conflict(new, entry, new_type);
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if (!err) {
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dprintk("Overlap at 0x%Lx-0x%Lx\n",
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entry->start, entry->end);
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where = entry->nd.prev;
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cached_entry = list_entry(where,
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struct memtype, nd);
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}
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break;
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} else if (start < entry->end) { /* start > entry->start */
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err = chk_conflict(new, entry, new_type);
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if (!err) {
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dprintk("Overlap at 0x%Lx-0x%Lx\n",
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entry->start, entry->end);
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cached_entry = list_entry(entry->nd.prev,
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struct memtype, nd);
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/*
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* Move to right position in the linked
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* list to add this new entry
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*/
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list_for_each_entry_continue(entry,
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&memtype_list, nd) {
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if (start <= entry->start) {
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where = entry->nd.prev;
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break;
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}
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}
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}
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break;
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}
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}
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if (err) {
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printk(KERN_INFO "reserve_memtype failed 0x%Lx-0x%Lx, "
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"track %s, req %s\n",
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start, end, cattr_name(new->type), cattr_name(req_type));
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kfree(new);
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spin_unlock(&memtype_lock);
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return err;
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}
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cached_start = start;
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|
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if (where)
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list_add(&new->nd, where);
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else
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list_add_tail(&new->nd, &memtype_list);
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spin_unlock(&memtype_lock);
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dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
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start, end, cattr_name(new->type), cattr_name(req_type),
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new_type ? cattr_name(*new_type) : "-");
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return err;
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}
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int free_memtype(u64 start, u64 end)
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{
|
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struct memtype *entry;
|
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int err = -EINVAL;
|
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int is_range_ram;
|
|
|
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if (!pat_enabled)
|
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return 0;
|
|
|
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/* Low ISA region is always mapped WB. No need to track */
|
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if (is_ISA_range(start, end - 1))
|
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return 0;
|
|
|
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is_range_ram = pagerange_is_ram(start, end);
|
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if (is_range_ram == 1)
|
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return free_ram_pages_type(start, end);
|
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else if (is_range_ram < 0)
|
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return -EINVAL;
|
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|
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spin_lock(&memtype_lock);
|
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list_for_each_entry(entry, &memtype_list, nd) {
|
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if (entry->start == start && entry->end == end) {
|
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if (cached_entry == entry || cached_start == start)
|
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cached_entry = NULL;
|
|
|
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list_del(&entry->nd);
|
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kfree(entry);
|
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err = 0;
|
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break;
|
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}
|
|
}
|
|
spin_unlock(&memtype_lock);
|
|
|
|
if (err) {
|
|
printk(KERN_INFO "%s:%d freeing invalid memtype %Lx-%Lx\n",
|
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current->comm, current->pid, start, end);
|
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}
|
|
|
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dprintk("free_memtype request 0x%Lx-0x%Lx\n", start, end);
|
|
|
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return err;
|
|
}
|
|
|
|
|
|
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
|
|
unsigned long size, pgprot_t vma_prot)
|
|
{
|
|
return vma_prot;
|
|
}
|
|
|
|
#ifdef CONFIG_STRICT_DEVMEM
|
|
/* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/
|
|
static inline int range_is_allowed(unsigned long pfn, unsigned long size)
|
|
{
|
|
return 1;
|
|
}
|
|
#else
|
|
/* This check is needed to avoid cache aliasing when PAT is enabled */
|
|
static inline int range_is_allowed(unsigned long pfn, unsigned long size)
|
|
{
|
|
u64 from = ((u64)pfn) << PAGE_SHIFT;
|
|
u64 to = from + size;
|
|
u64 cursor = from;
|
|
|
|
if (!pat_enabled)
|
|
return 1;
|
|
|
|
while (cursor < to) {
|
|
if (!devmem_is_allowed(pfn)) {
|
|
printk(KERN_INFO
|
|
"Program %s tried to access /dev/mem between %Lx->%Lx.\n",
|
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current->comm, from, to);
|
|
return 0;
|
|
}
|
|
cursor += PAGE_SIZE;
|
|
pfn++;
|
|
}
|
|
return 1;
|
|
}
|
|
#endif /* CONFIG_STRICT_DEVMEM */
|
|
|
|
int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
|
|
unsigned long size, pgprot_t *vma_prot)
|
|
{
|
|
u64 offset = ((u64) pfn) << PAGE_SHIFT;
|
|
unsigned long flags = -1;
|
|
int retval;
|
|
|
|
if (!range_is_allowed(pfn, size))
|
|
return 0;
|
|
|
|
if (file->f_flags & O_SYNC) {
|
|
flags = _PAGE_CACHE_UC_MINUS;
|
|
}
|
|
|
|
#ifdef CONFIG_X86_32
|
|
/*
|
|
* On the PPro and successors, the MTRRs are used to set
|
|
* memory types for physical addresses outside main memory,
|
|
* so blindly setting UC or PWT on those pages is wrong.
|
|
* For Pentiums and earlier, the surround logic should disable
|
|
* caching for the high addresses through the KEN pin, but
|
|
* we maintain the tradition of paranoia in this code.
|
|
*/
|
|
if (!pat_enabled &&
|
|
!(boot_cpu_has(X86_FEATURE_MTRR) ||
|
|
boot_cpu_has(X86_FEATURE_K6_MTRR) ||
|
|
boot_cpu_has(X86_FEATURE_CYRIX_ARR) ||
|
|
boot_cpu_has(X86_FEATURE_CENTAUR_MCR)) &&
|
|
(pfn << PAGE_SHIFT) >= __pa(high_memory)) {
|
|
flags = _PAGE_CACHE_UC;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* With O_SYNC, we can only take UC_MINUS mapping. Fail if we cannot.
|
|
*
|
|
* Without O_SYNC, we want to get
|
|
* - WB for WB-able memory and no other conflicting mappings
|
|
* - UC_MINUS for non-WB-able memory with no other conflicting mappings
|
|
* - Inherit from confliting mappings otherwise
|
|
*/
|
|
if (flags != -1) {
|
|
retval = reserve_memtype(offset, offset + size, flags, NULL);
|
|
} else {
|
|
retval = reserve_memtype(offset, offset + size, -1, &flags);
|
|
}
|
|
|
|
if (retval < 0)
|
|
return 0;
|
|
|
|
if (((pfn < max_low_pfn_mapped) ||
|
|
(pfn >= (1UL<<(32 - PAGE_SHIFT)) && pfn < max_pfn_mapped)) &&
|
|
ioremap_change_attr((unsigned long)__va(offset), size, flags) < 0) {
|
|
free_memtype(offset, offset + size);
|
|
printk(KERN_INFO
|
|
"%s:%d /dev/mem ioremap_change_attr failed %s for %Lx-%Lx\n",
|
|
current->comm, current->pid,
|
|
cattr_name(flags),
|
|
offset, (unsigned long long)(offset + size));
|
|
return 0;
|
|
}
|
|
|
|
*vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
|
|
flags);
|
|
return 1;
|
|
}
|
|
|
|
void map_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot)
|
|
{
|
|
unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK);
|
|
u64 addr = (u64)pfn << PAGE_SHIFT;
|
|
unsigned long flags;
|
|
|
|
reserve_memtype(addr, addr + size, want_flags, &flags);
|
|
if (flags != want_flags) {
|
|
printk(KERN_INFO
|
|
"%s:%d /dev/mem expected mapping type %s for %Lx-%Lx, got %s\n",
|
|
current->comm, current->pid,
|
|
cattr_name(want_flags),
|
|
addr, (unsigned long long)(addr + size),
|
|
cattr_name(flags));
|
|
}
|
|
}
|
|
|
|
void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot)
|
|
{
|
|
u64 addr = (u64)pfn << PAGE_SHIFT;
|
|
|
|
free_memtype(addr, addr + size);
|
|
}
|
|
|
|
/*
|
|
* Internal interface to reserve a range of physical memory with prot.
|
|
* Reserved non RAM regions only and after successful reserve_memtype,
|
|
* this func also keeps identity mapping (if any) in sync with this new prot.
|
|
*/
|
|
static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t vma_prot)
|
|
{
|
|
int is_ram = 0;
|
|
int id_sz, ret;
|
|
unsigned long flags;
|
|
unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK);
|
|
|
|
is_ram = pagerange_is_ram(paddr, paddr + size);
|
|
|
|
if (is_ram != 0) {
|
|
/*
|
|
* For mapping RAM pages, drivers need to call
|
|
* set_memory_[uc|wc|wb] directly, for reserve and free, before
|
|
* setting up the PTE.
|
|
*/
|
|
WARN_ON_ONCE(1);
|
|
return 0;
|
|
}
|
|
|
|
ret = reserve_memtype(paddr, paddr + size, want_flags, &flags);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (flags != want_flags) {
|
|
free_memtype(paddr, paddr + size);
|
|
printk(KERN_ERR
|
|
"%s:%d map pfn expected mapping type %s for %Lx-%Lx, got %s\n",
|
|
current->comm, current->pid,
|
|
cattr_name(want_flags),
|
|
(unsigned long long)paddr,
|
|
(unsigned long long)(paddr + size),
|
|
cattr_name(flags));
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Need to keep identity mapping in sync */
|
|
if (paddr >= __pa(high_memory))
|
|
return 0;
|
|
|
|
id_sz = (__pa(high_memory) < paddr + size) ?
|
|
__pa(high_memory) - paddr :
|
|
size;
|
|
|
|
if (ioremap_change_attr((unsigned long)__va(paddr), id_sz, flags) < 0) {
|
|
free_memtype(paddr, paddr + size);
|
|
printk(KERN_ERR
|
|
"%s:%d reserve_pfn_range ioremap_change_attr failed %s "
|
|
"for %Lx-%Lx\n",
|
|
current->comm, current->pid,
|
|
cattr_name(flags),
|
|
(unsigned long long)paddr,
|
|
(unsigned long long)(paddr + size));
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Internal interface to free a range of physical memory.
|
|
* Frees non RAM regions only.
|
|
*/
|
|
static void free_pfn_range(u64 paddr, unsigned long size)
|
|
{
|
|
int is_ram;
|
|
|
|
is_ram = pagerange_is_ram(paddr, paddr + size);
|
|
if (is_ram == 0)
|
|
free_memtype(paddr, paddr + size);
|
|
}
|
|
|
|
/*
|
|
* track_pfn_vma_copy is called when vma that is covering the pfnmap gets
|
|
* copied through copy_page_range().
|
|
*
|
|
* If the vma has a linear pfn mapping for the entire range, we get the prot
|
|
* from pte and reserve the entire vma range with single reserve_pfn_range call.
|
|
* Otherwise, we reserve the entire vma range, my ging through the PTEs page
|
|
* by page to get physical address and protection.
|
|
*/
|
|
int track_pfn_vma_copy(struct vm_area_struct *vma)
|
|
{
|
|
int retval = 0;
|
|
unsigned long i, j;
|
|
u64 paddr;
|
|
unsigned long prot;
|
|
unsigned long vma_start = vma->vm_start;
|
|
unsigned long vma_end = vma->vm_end;
|
|
unsigned long vma_size = vma_end - vma_start;
|
|
|
|
if (!pat_enabled)
|
|
return 0;
|
|
|
|
if (is_linear_pfn_mapping(vma)) {
|
|
/*
|
|
* reserve the whole chunk covered by vma. We need the
|
|
* starting address and protection from pte.
|
|
*/
|
|
if (follow_phys(vma, vma_start, 0, &prot, &paddr)) {
|
|
WARN_ON_ONCE(1);
|
|
return -EINVAL;
|
|
}
|
|
return reserve_pfn_range(paddr, vma_size, __pgprot(prot));
|
|
}
|
|
|
|
/* reserve entire vma page by page, using pfn and prot from pte */
|
|
for (i = 0; i < vma_size; i += PAGE_SIZE) {
|
|
if (follow_phys(vma, vma_start + i, 0, &prot, &paddr))
|
|
continue;
|
|
|
|
retval = reserve_pfn_range(paddr, PAGE_SIZE, __pgprot(prot));
|
|
if (retval)
|
|
goto cleanup_ret;
|
|
}
|
|
return 0;
|
|
|
|
cleanup_ret:
|
|
/* Reserve error: Cleanup partial reservation and return error */
|
|
for (j = 0; j < i; j += PAGE_SIZE) {
|
|
if (follow_phys(vma, vma_start + j, 0, &prot, &paddr))
|
|
continue;
|
|
|
|
free_pfn_range(paddr, PAGE_SIZE);
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* track_pfn_vma_new is called when a _new_ pfn mapping is being established
|
|
* for physical range indicated by pfn and size.
|
|
*
|
|
* prot is passed in as a parameter for the new mapping. If the vma has a
|
|
* linear pfn mapping for the entire range reserve the entire vma range with
|
|
* single reserve_pfn_range call.
|
|
* Otherwise, we look t the pfn and size and reserve only the specified range
|
|
* page by page.
|
|
*
|
|
* Note that this function can be called with caller trying to map only a
|
|
* subrange/page inside the vma.
|
|
*/
|
|
int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot,
|
|
unsigned long pfn, unsigned long size)
|
|
{
|
|
int retval = 0;
|
|
unsigned long i, j;
|
|
u64 base_paddr;
|
|
u64 paddr;
|
|
unsigned long vma_start = vma->vm_start;
|
|
unsigned long vma_end = vma->vm_end;
|
|
unsigned long vma_size = vma_end - vma_start;
|
|
|
|
if (!pat_enabled)
|
|
return 0;
|
|
|
|
if (is_linear_pfn_mapping(vma)) {
|
|
/* reserve the whole chunk starting from vm_pgoff */
|
|
paddr = (u64)vma->vm_pgoff << PAGE_SHIFT;
|
|
return reserve_pfn_range(paddr, vma_size, prot);
|
|
}
|
|
|
|
/* reserve page by page using pfn and size */
|
|
base_paddr = (u64)pfn << PAGE_SHIFT;
|
|
for (i = 0; i < size; i += PAGE_SIZE) {
|
|
paddr = base_paddr + i;
|
|
retval = reserve_pfn_range(paddr, PAGE_SIZE, prot);
|
|
if (retval)
|
|
goto cleanup_ret;
|
|
}
|
|
return 0;
|
|
|
|
cleanup_ret:
|
|
/* Reserve error: Cleanup partial reservation and return error */
|
|
for (j = 0; j < i; j += PAGE_SIZE) {
|
|
paddr = base_paddr + j;
|
|
free_pfn_range(paddr, PAGE_SIZE);
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* untrack_pfn_vma is called while unmapping a pfnmap for a region.
|
|
* untrack can be called for a specific region indicated by pfn and size or
|
|
* can be for the entire vma (in which case size can be zero).
|
|
*/
|
|
void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
|
|
unsigned long size)
|
|
{
|
|
unsigned long i;
|
|
u64 paddr;
|
|
unsigned long prot;
|
|
unsigned long vma_start = vma->vm_start;
|
|
unsigned long vma_end = vma->vm_end;
|
|
unsigned long vma_size = vma_end - vma_start;
|
|
|
|
if (!pat_enabled)
|
|
return;
|
|
|
|
if (is_linear_pfn_mapping(vma)) {
|
|
/* free the whole chunk starting from vm_pgoff */
|
|
paddr = (u64)vma->vm_pgoff << PAGE_SHIFT;
|
|
free_pfn_range(paddr, vma_size);
|
|
return;
|
|
}
|
|
|
|
if (size != 0 && size != vma_size) {
|
|
/* free page by page, using pfn and size */
|
|
paddr = (u64)pfn << PAGE_SHIFT;
|
|
for (i = 0; i < size; i += PAGE_SIZE) {
|
|
paddr = paddr + i;
|
|
free_pfn_range(paddr, PAGE_SIZE);
|
|
}
|
|
} else {
|
|
/* free entire vma, page by page, using the pfn from pte */
|
|
for (i = 0; i < vma_size; i += PAGE_SIZE) {
|
|
if (follow_phys(vma, vma_start + i, 0, &prot, &paddr))
|
|
continue;
|
|
|
|
free_pfn_range(paddr, PAGE_SIZE);
|
|
}
|
|
}
|
|
}
|
|
|
|
pgprot_t pgprot_writecombine(pgprot_t prot)
|
|
{
|
|
if (pat_enabled)
|
|
return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC);
|
|
else
|
|
return pgprot_noncached(prot);
|
|
}
|
|
|
|
#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
|
|
|
|
/* get Nth element of the linked list */
|
|
static struct memtype *memtype_get_idx(loff_t pos)
|
|
{
|
|
struct memtype *list_node, *print_entry;
|
|
int i = 1;
|
|
|
|
print_entry = kmalloc(sizeof(struct memtype), GFP_KERNEL);
|
|
if (!print_entry)
|
|
return NULL;
|
|
|
|
spin_lock(&memtype_lock);
|
|
list_for_each_entry(list_node, &memtype_list, nd) {
|
|
if (pos == i) {
|
|
*print_entry = *list_node;
|
|
spin_unlock(&memtype_lock);
|
|
return print_entry;
|
|
}
|
|
++i;
|
|
}
|
|
spin_unlock(&memtype_lock);
|
|
kfree(print_entry);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
if (*pos == 0) {
|
|
++*pos;
|
|
seq_printf(seq, "PAT memtype list:\n");
|
|
}
|
|
|
|
return memtype_get_idx(*pos);
|
|
}
|
|
|
|
static void *memtype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
++*pos;
|
|
return memtype_get_idx(*pos);
|
|
}
|
|
|
|
static void memtype_seq_stop(struct seq_file *seq, void *v)
|
|
{
|
|
}
|
|
|
|
static int memtype_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
struct memtype *print_entry = (struct memtype *)v;
|
|
|
|
seq_printf(seq, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry->type),
|
|
print_entry->start, print_entry->end);
|
|
kfree(print_entry);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct seq_operations memtype_seq_ops = {
|
|
.start = memtype_seq_start,
|
|
.next = memtype_seq_next,
|
|
.stop = memtype_seq_stop,
|
|
.show = memtype_seq_show,
|
|
};
|
|
|
|
static int memtype_seq_open(struct inode *inode, struct file *file)
|
|
{
|
|
return seq_open(file, &memtype_seq_ops);
|
|
}
|
|
|
|
static const struct file_operations memtype_fops = {
|
|
.open = memtype_seq_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release,
|
|
};
|
|
|
|
static int __init pat_memtype_list_init(void)
|
|
{
|
|
debugfs_create_file("pat_memtype_list", S_IRUSR, arch_debugfs_dir,
|
|
NULL, &memtype_fops);
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(pat_memtype_list_init);
|
|
|
|
#endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */
|