2 * Handle caching attributes in page tables (PAT)
4 * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Suresh B Siddha <suresh.b.siddha@intel.com>
7 * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
10 #include <linux/seq_file.h>
11 #include <linux/bootmem.h>
12 #include <linux/debugfs.h>
13 #include <linux/kernel.h>
14 #include <linux/gfp.h>
18 #include <asm/cacheflush.h>
19 #include <asm/processor.h>
20 #include <asm/tlbflush.h>
21 #include <asm/pgtable.h>
22 #include <asm/fcntl.h>
31 int __read_mostly pat_enabled
= 1;
33 void __cpuinit
pat_disable(char *reason
)
36 printk(KERN_INFO
"%s\n", reason
);
39 static int __init
nopat(char *str
)
41 pat_disable("PAT support disabled.");
44 early_param("nopat", nopat
);
48 static int debug_enable
;
50 static int __init
pat_debug_setup(char *str
)
55 __setup("debugpat", pat_debug_setup
);
57 #define dprintk(fmt, arg...) \
58 do { if (debug_enable) printk(KERN_INFO fmt, ##arg); } while (0)
61 static u64 __read_mostly boot_pat_state
;
64 PAT_UC
= 0, /* uncached */
65 PAT_WC
= 1, /* Write combining */
66 PAT_WT
= 4, /* Write Through */
67 PAT_WP
= 5, /* Write Protected */
68 PAT_WB
= 6, /* Write Back (default) */
69 PAT_UC_MINUS
= 7, /* UC, but can be overriden by MTRR */
72 #define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
82 if (!cpu_has_pat
&& boot_pat_state
) {
84 * If this happens we are on a secondary CPU, but
85 * switched to PAT on the boot CPU. We have no way to
88 printk(KERN_ERR
"PAT enabled, "
89 "but not supported by secondary CPU\n");
93 /* Set PWT to Write-Combining. All other bits stay the same */
95 * PTE encoding used in Linux:
100 * 000 WB _PAGE_CACHE_WB
101 * 001 WC _PAGE_CACHE_WC
102 * 010 UC- _PAGE_CACHE_UC_MINUS
103 * 011 UC _PAGE_CACHE_UC
106 pat
= PAT(0, WB
) | PAT(1, WC
) | PAT(2, UC_MINUS
) | PAT(3, UC
) |
107 PAT(4, WB
) | PAT(5, WC
) | PAT(6, UC_MINUS
) | PAT(7, UC
);
111 rdmsrl(MSR_IA32_CR_PAT
, boot_pat_state
);
113 wrmsrl(MSR_IA32_CR_PAT
, pat
);
114 printk(KERN_INFO
"x86 PAT enabled: cpu %d, old 0x%Lx, new 0x%Lx\n",
115 smp_processor_id(), boot_pat_state
, pat
);
120 static char *cattr_name(unsigned long flags
)
122 switch (flags
& _PAGE_CACHE_MASK
) {
123 case _PAGE_CACHE_UC
: return "uncached";
124 case _PAGE_CACHE_UC_MINUS
: return "uncached-minus";
125 case _PAGE_CACHE_WB
: return "write-back";
126 case _PAGE_CACHE_WC
: return "write-combining";
127 default: return "broken";
132 * The global memtype list keeps track of memory type for specific
133 * physical memory areas. Conflicting memory types in different
134 * mappings can cause CPU cache corruption. To avoid this we keep track.
136 * The list is sorted based on starting address and can contain multiple
137 * entries for each address (this allows reference counting for overlapping
138 * areas). All the aliases have the same cache attributes of course.
139 * Zero attributes are represented as holes.
141 * Currently the data structure is a list because the number of mappings
142 * are expected to be relatively small. If this should be a problem
143 * it could be changed to a rbtree or similar.
145 * memtype_lock protects the whole list.
155 static LIST_HEAD(memtype_list
);
156 static DEFINE_SPINLOCK(memtype_lock
); /* protects memtype list */
159 * Does intersection of PAT memory type and MTRR memory type and returns
160 * the resulting memory type as PAT understands it.
161 * (Type in pat and mtrr will not have same value)
162 * The intersection is based on "Effective Memory Type" tables in IA-32
165 static unsigned long pat_x_mtrr_type(u64 start
, u64 end
, unsigned long req_type
)
168 * Look for MTRR hint to get the effective type in case where PAT
171 if (req_type
== _PAGE_CACHE_WB
) {
174 mtrr_type
= mtrr_type_lookup(start
, end
);
175 if (mtrr_type
== MTRR_TYPE_UNCACHABLE
)
176 return _PAGE_CACHE_UC
;
177 if (mtrr_type
== MTRR_TYPE_WRCOMB
)
178 return _PAGE_CACHE_WC
;
185 chk_conflict(struct memtype
*new, struct memtype
*entry
, unsigned long *type
)
187 if (new->type
!= entry
->type
) {
189 new->type
= entry
->type
;
195 /* check overlaps with more than one entry in the list */
196 list_for_each_entry_continue(entry
, &memtype_list
, nd
) {
197 if (new->end
<= entry
->start
)
199 else if (new->type
!= entry
->type
)
205 printk(KERN_INFO
"%s:%d conflicting memory types "
206 "%Lx-%Lx %s<->%s\n", current
->comm
, current
->pid
, new->start
,
207 new->end
, cattr_name(new->type
), cattr_name(entry
->type
));
211 static struct memtype
*cached_entry
;
212 static u64 cached_start
;
215 * For RAM pages, mark the pages as non WB memory type using
216 * PageNonWB (PG_arch_1). We allow only one set_memory_uc() or
217 * set_memory_wc() on a RAM page at a time before marking it as WB again.
218 * This is ok, because only one driver will be owning the page and
219 * doing set_memory_*() calls.
221 * For now, we use PageNonWB to track that the RAM page is being mapped
222 * as non WB. In future, we will have to use one more flag
223 * (or some other mechanism in page_struct) to distinguish between
226 static int reserve_ram_pages_type(u64 start
, u64 end
, unsigned long req_type
,
227 unsigned long *new_type
)
232 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< (end
>> PAGE_SHIFT
); ++pfn
) {
233 page
= pfn_to_page(pfn
);
234 if (page_mapped(page
) || PageNonWB(page
))
243 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< end_pfn
; ++pfn
) {
244 page
= pfn_to_page(pfn
);
245 ClearPageNonWB(page
);
251 static int free_ram_pages_type(u64 start
, u64 end
)
256 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< (end
>> PAGE_SHIFT
); ++pfn
) {
257 page
= pfn_to_page(pfn
);
258 if (page_mapped(page
) || !PageNonWB(page
))
261 ClearPageNonWB(page
);
267 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< end_pfn
; ++pfn
) {
268 page
= pfn_to_page(pfn
);
275 * req_type typically has one of the:
278 * - _PAGE_CACHE_UC_MINUS
281 * req_type will have a special case value '-1', when requester want to inherit
282 * the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
284 * If new_type is NULL, function will return an error if it cannot reserve the
285 * region with req_type. If new_type is non-NULL, function will return
286 * available type in new_type in case of no error. In case of any error
287 * it will return a negative return value.
289 int reserve_memtype(u64 start
, u64 end
, unsigned long req_type
,
290 unsigned long *new_type
)
292 struct memtype
*new, *entry
;
293 unsigned long actual_type
;
294 struct list_head
*where
;
298 BUG_ON(start
>= end
); /* end is exclusive */
301 /* This is identical to page table setting without PAT */
304 *new_type
= _PAGE_CACHE_WB
;
306 *new_type
= req_type
& _PAGE_CACHE_MASK
;
311 /* Low ISA region is always mapped WB in page table. No need to track */
312 if (is_ISA_range(start
, end
- 1)) {
314 *new_type
= _PAGE_CACHE_WB
;
318 if (req_type
== -1) {
320 * Call mtrr_lookup to get the type hint. This is an
321 * optimization for /dev/mem mmap'ers into WB memory (BIOS
322 * tools and ACPI tools). Use WB request for WB memory and use
323 * UC_MINUS otherwise.
325 u8 mtrr_type
= mtrr_type_lookup(start
, end
);
327 if (mtrr_type
== MTRR_TYPE_WRBACK
)
328 actual_type
= _PAGE_CACHE_WB
;
330 actual_type
= _PAGE_CACHE_UC_MINUS
;
332 actual_type
= pat_x_mtrr_type(start
, end
,
333 req_type
& _PAGE_CACHE_MASK
);
337 * For legacy reasons, some parts of the physical address range in the
338 * legacy 1MB region is treated as non-RAM (even when listed as RAM in
339 * the e820 tables). So we will track the memory attributes of this
340 * legacy 1MB region using the linear memtype_list always.
342 if (end
>= ISA_END_ADDRESS
) {
343 is_range_ram
= pagerange_is_ram(start
, end
);
344 if (is_range_ram
== 1)
345 return reserve_ram_pages_type(start
, end
, req_type
,
347 else if (is_range_ram
< 0)
351 new = kmalloc(sizeof(struct memtype
), GFP_KERNEL
);
357 new->type
= actual_type
;
360 *new_type
= actual_type
;
362 spin_lock(&memtype_lock
);
364 if (cached_entry
&& start
>= cached_start
)
365 entry
= cached_entry
;
367 entry
= list_entry(&memtype_list
, struct memtype
, nd
);
369 /* Search for existing mapping that overlaps the current range */
371 list_for_each_entry_continue(entry
, &memtype_list
, nd
) {
372 if (end
<= entry
->start
) {
373 where
= entry
->nd
.prev
;
374 cached_entry
= list_entry(where
, struct memtype
, nd
);
376 } else if (start
<= entry
->start
) { /* end > entry->start */
377 err
= chk_conflict(new, entry
, new_type
);
379 dprintk("Overlap at 0x%Lx-0x%Lx\n",
380 entry
->start
, entry
->end
);
381 where
= entry
->nd
.prev
;
382 cached_entry
= list_entry(where
,
386 } else if (start
< entry
->end
) { /* start > entry->start */
387 err
= chk_conflict(new, entry
, new_type
);
389 dprintk("Overlap at 0x%Lx-0x%Lx\n",
390 entry
->start
, entry
->end
);
391 cached_entry
= list_entry(entry
->nd
.prev
,
395 * Move to right position in the linked
396 * list to add this new entry
398 list_for_each_entry_continue(entry
,
400 if (start
<= entry
->start
) {
401 where
= entry
->nd
.prev
;
411 printk(KERN_INFO
"reserve_memtype failed 0x%Lx-0x%Lx, "
412 "track %s, req %s\n",
413 start
, end
, cattr_name(new->type
), cattr_name(req_type
));
415 spin_unlock(&memtype_lock
);
420 cached_start
= start
;
423 list_add(&new->nd
, where
);
425 list_add_tail(&new->nd
, &memtype_list
);
427 spin_unlock(&memtype_lock
);
429 dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
430 start
, end
, cattr_name(new->type
), cattr_name(req_type
),
431 new_type
? cattr_name(*new_type
) : "-");
436 int free_memtype(u64 start
, u64 end
)
438 struct memtype
*entry
;
445 /* Low ISA region is always mapped WB. No need to track */
446 if (is_ISA_range(start
, end
- 1))
450 * For legacy reasons, some parts of the physical address range in the
451 * legacy 1MB region is treated as non-RAM (even when listed as RAM in
452 * the e820 tables). So we will track the memory attributes of this
453 * legacy 1MB region using the linear memtype_list always.
455 if (end
>= ISA_END_ADDRESS
) {
456 is_range_ram
= pagerange_is_ram(start
, end
);
457 if (is_range_ram
== 1)
458 return free_ram_pages_type(start
, end
);
459 else if (is_range_ram
< 0)
463 spin_lock(&memtype_lock
);
464 list_for_each_entry(entry
, &memtype_list
, nd
) {
465 if (entry
->start
== start
&& entry
->end
== end
) {
466 if (cached_entry
== entry
|| cached_start
== start
)
469 list_del(&entry
->nd
);
475 spin_unlock(&memtype_lock
);
478 printk(KERN_INFO
"%s:%d freeing invalid memtype %Lx-%Lx\n",
479 current
->comm
, current
->pid
, start
, end
);
482 dprintk("free_memtype request 0x%Lx-0x%Lx\n", start
, end
);
488 pgprot_t
phys_mem_access_prot(struct file
*file
, unsigned long pfn
,
489 unsigned long size
, pgprot_t vma_prot
)
494 #ifdef CONFIG_STRICT_DEVMEM
495 /* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/
496 static inline int range_is_allowed(unsigned long pfn
, unsigned long size
)
501 /* This check is needed to avoid cache aliasing when PAT is enabled */
502 static inline int range_is_allowed(unsigned long pfn
, unsigned long size
)
504 u64 from
= ((u64
)pfn
) << PAGE_SHIFT
;
505 u64 to
= from
+ size
;
511 while (cursor
< to
) {
512 if (!devmem_is_allowed(pfn
)) {
514 "Program %s tried to access /dev/mem between %Lx->%Lx.\n",
515 current
->comm
, from
, to
);
523 #endif /* CONFIG_STRICT_DEVMEM */
525 int phys_mem_access_prot_allowed(struct file
*file
, unsigned long pfn
,
526 unsigned long size
, pgprot_t
*vma_prot
)
528 u64 offset
= ((u64
) pfn
) << PAGE_SHIFT
;
529 unsigned long flags
= -1;
532 if (!range_is_allowed(pfn
, size
))
535 if (file
->f_flags
& O_SYNC
) {
536 flags
= _PAGE_CACHE_UC_MINUS
;
541 * On the PPro and successors, the MTRRs are used to set
542 * memory types for physical addresses outside main memory,
543 * so blindly setting UC or PWT on those pages is wrong.
544 * For Pentiums and earlier, the surround logic should disable
545 * caching for the high addresses through the KEN pin, but
546 * we maintain the tradition of paranoia in this code.
549 !(boot_cpu_has(X86_FEATURE_MTRR
) ||
550 boot_cpu_has(X86_FEATURE_K6_MTRR
) ||
551 boot_cpu_has(X86_FEATURE_CYRIX_ARR
) ||
552 boot_cpu_has(X86_FEATURE_CENTAUR_MCR
)) &&
553 (pfn
<< PAGE_SHIFT
) >= __pa(high_memory
)) {
554 flags
= _PAGE_CACHE_UC
;
559 * With O_SYNC, we can only take UC_MINUS mapping. Fail if we cannot.
561 * Without O_SYNC, we want to get
562 * - WB for WB-able memory and no other conflicting mappings
563 * - UC_MINUS for non-WB-able memory with no other conflicting mappings
564 * - Inherit from confliting mappings otherwise
567 retval
= reserve_memtype(offset
, offset
+ size
, flags
, NULL
);
569 retval
= reserve_memtype(offset
, offset
+ size
, -1, &flags
);
575 if (((pfn
< max_low_pfn_mapped
) ||
576 (pfn
>= (1UL<<(32 - PAGE_SHIFT
)) && pfn
< max_pfn_mapped
)) &&
577 ioremap_change_attr((unsigned long)__va(offset
), size
, flags
) < 0) {
578 free_memtype(offset
, offset
+ size
);
580 "%s:%d /dev/mem ioremap_change_attr failed %s for %Lx-%Lx\n",
581 current
->comm
, current
->pid
,
583 offset
, (unsigned long long)(offset
+ size
));
587 *vma_prot
= __pgprot((pgprot_val(*vma_prot
) & ~_PAGE_CACHE_MASK
) |
592 void map_devmem(unsigned long pfn
, unsigned long size
, pgprot_t vma_prot
)
594 unsigned long want_flags
= (pgprot_val(vma_prot
) & _PAGE_CACHE_MASK
);
595 u64 addr
= (u64
)pfn
<< PAGE_SHIFT
;
598 reserve_memtype(addr
, addr
+ size
, want_flags
, &flags
);
599 if (flags
!= want_flags
) {
601 "%s:%d /dev/mem expected mapping type %s for %Lx-%Lx, got %s\n",
602 current
->comm
, current
->pid
,
603 cattr_name(want_flags
),
604 addr
, (unsigned long long)(addr
+ size
),
609 void unmap_devmem(unsigned long pfn
, unsigned long size
, pgprot_t vma_prot
)
611 u64 addr
= (u64
)pfn
<< PAGE_SHIFT
;
613 free_memtype(addr
, addr
+ size
);
617 * Internal interface to reserve a range of physical memory with prot.
618 * Reserved non RAM regions only and after successful reserve_memtype,
619 * this func also keeps identity mapping (if any) in sync with this new prot.
621 static int reserve_pfn_range(u64 paddr
, unsigned long size
, pgprot_t vma_prot
)
626 unsigned long want_flags
= (pgprot_val(vma_prot
) & _PAGE_CACHE_MASK
);
628 is_ram
= pagerange_is_ram(paddr
, paddr
+ size
);
632 * For mapping RAM pages, drivers need to call
633 * set_memory_[uc|wc|wb] directly, for reserve and free, before
634 * setting up the PTE.
640 ret
= reserve_memtype(paddr
, paddr
+ size
, want_flags
, &flags
);
644 if (flags
!= want_flags
) {
645 free_memtype(paddr
, paddr
+ size
);
647 "%s:%d map pfn expected mapping type %s for %Lx-%Lx, got %s\n",
648 current
->comm
, current
->pid
,
649 cattr_name(want_flags
),
650 (unsigned long long)paddr
,
651 (unsigned long long)(paddr
+ size
),
656 /* Need to keep identity mapping in sync */
657 if (paddr
>= __pa(high_memory
))
660 id_sz
= (__pa(high_memory
) < paddr
+ size
) ?
661 __pa(high_memory
) - paddr
:
664 if (ioremap_change_attr((unsigned long)__va(paddr
), id_sz
, flags
) < 0) {
665 free_memtype(paddr
, paddr
+ size
);
667 "%s:%d reserve_pfn_range ioremap_change_attr failed %s "
669 current
->comm
, current
->pid
,
671 (unsigned long long)paddr
,
672 (unsigned long long)(paddr
+ size
));
679 * Internal interface to free a range of physical memory.
680 * Frees non RAM regions only.
682 static void free_pfn_range(u64 paddr
, unsigned long size
)
686 is_ram
= pagerange_is_ram(paddr
, paddr
+ size
);
688 free_memtype(paddr
, paddr
+ size
);
692 * track_pfn_vma_copy is called when vma that is covering the pfnmap gets
693 * copied through copy_page_range().
695 * If the vma has a linear pfn mapping for the entire range, we get the prot
696 * from pte and reserve the entire vma range with single reserve_pfn_range call.
697 * Otherwise, we reserve the entire vma range, my ging through the PTEs page
698 * by page to get physical address and protection.
700 int track_pfn_vma_copy(struct vm_area_struct
*vma
)
704 resource_size_t paddr
;
706 unsigned long vma_start
= vma
->vm_start
;
707 unsigned long vma_end
= vma
->vm_end
;
708 unsigned long vma_size
= vma_end
- vma_start
;
713 if (is_linear_pfn_mapping(vma
)) {
715 * reserve the whole chunk covered by vma. We need the
716 * starting address and protection from pte.
718 if (follow_phys(vma
, vma_start
, 0, &prot
, &paddr
)) {
722 return reserve_pfn_range(paddr
, vma_size
, __pgprot(prot
));
725 /* reserve entire vma page by page, using pfn and prot from pte */
726 for (i
= 0; i
< vma_size
; i
+= PAGE_SIZE
) {
727 if (follow_phys(vma
, vma_start
+ i
, 0, &prot
, &paddr
))
730 retval
= reserve_pfn_range(paddr
, PAGE_SIZE
, __pgprot(prot
));
737 /* Reserve error: Cleanup partial reservation and return error */
738 for (j
= 0; j
< i
; j
+= PAGE_SIZE
) {
739 if (follow_phys(vma
, vma_start
+ j
, 0, &prot
, &paddr
))
742 free_pfn_range(paddr
, PAGE_SIZE
);
749 * track_pfn_vma_new is called when a _new_ pfn mapping is being established
750 * for physical range indicated by pfn and size.
752 * prot is passed in as a parameter for the new mapping. If the vma has a
753 * linear pfn mapping for the entire range reserve the entire vma range with
754 * single reserve_pfn_range call.
755 * Otherwise, we look t the pfn and size and reserve only the specified range
758 * Note that this function can be called with caller trying to map only a
759 * subrange/page inside the vma.
761 int track_pfn_vma_new(struct vm_area_struct
*vma
, pgprot_t prot
,
762 unsigned long pfn
, unsigned long size
)
766 resource_size_t base_paddr
;
767 resource_size_t paddr
;
768 unsigned long vma_start
= vma
->vm_start
;
769 unsigned long vma_end
= vma
->vm_end
;
770 unsigned long vma_size
= vma_end
- vma_start
;
775 if (is_linear_pfn_mapping(vma
)) {
776 /* reserve the whole chunk starting from vm_pgoff */
777 paddr
= (resource_size_t
)vma
->vm_pgoff
<< PAGE_SHIFT
;
778 return reserve_pfn_range(paddr
, vma_size
, prot
);
781 /* reserve page by page using pfn and size */
782 base_paddr
= (resource_size_t
)pfn
<< PAGE_SHIFT
;
783 for (i
= 0; i
< size
; i
+= PAGE_SIZE
) {
784 paddr
= base_paddr
+ i
;
785 retval
= reserve_pfn_range(paddr
, PAGE_SIZE
, prot
);
792 /* Reserve error: Cleanup partial reservation and return error */
793 for (j
= 0; j
< i
; j
+= PAGE_SIZE
) {
794 paddr
= base_paddr
+ j
;
795 free_pfn_range(paddr
, PAGE_SIZE
);
802 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
803 * untrack can be called for a specific region indicated by pfn and size or
804 * can be for the entire vma (in which case size can be zero).
806 void untrack_pfn_vma(struct vm_area_struct
*vma
, unsigned long pfn
,
810 resource_size_t paddr
;
812 unsigned long vma_start
= vma
->vm_start
;
813 unsigned long vma_end
= vma
->vm_end
;
814 unsigned long vma_size
= vma_end
- vma_start
;
819 if (is_linear_pfn_mapping(vma
)) {
820 /* free the whole chunk starting from vm_pgoff */
821 paddr
= (resource_size_t
)vma
->vm_pgoff
<< PAGE_SHIFT
;
822 free_pfn_range(paddr
, vma_size
);
826 if (size
!= 0 && size
!= vma_size
) {
827 /* free page by page, using pfn and size */
828 paddr
= (resource_size_t
)pfn
<< PAGE_SHIFT
;
829 for (i
= 0; i
< size
; i
+= PAGE_SIZE
) {
831 free_pfn_range(paddr
, PAGE_SIZE
);
834 /* free entire vma, page by page, using the pfn from pte */
835 for (i
= 0; i
< vma_size
; i
+= PAGE_SIZE
) {
836 if (follow_phys(vma
, vma_start
+ i
, 0, &prot
, &paddr
))
839 free_pfn_range(paddr
, PAGE_SIZE
);
844 pgprot_t
pgprot_writecombine(pgprot_t prot
)
847 return __pgprot(pgprot_val(prot
) | _PAGE_CACHE_WC
);
849 return pgprot_noncached(prot
);
852 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
854 /* get Nth element of the linked list */
855 static struct memtype
*memtype_get_idx(loff_t pos
)
857 struct memtype
*list_node
, *print_entry
;
860 print_entry
= kmalloc(sizeof(struct memtype
), GFP_KERNEL
);
864 spin_lock(&memtype_lock
);
865 list_for_each_entry(list_node
, &memtype_list
, nd
) {
867 *print_entry
= *list_node
;
868 spin_unlock(&memtype_lock
);
873 spin_unlock(&memtype_lock
);
879 static void *memtype_seq_start(struct seq_file
*seq
, loff_t
*pos
)
883 seq_printf(seq
, "PAT memtype list:\n");
886 return memtype_get_idx(*pos
);
889 static void *memtype_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
892 return memtype_get_idx(*pos
);
895 static void memtype_seq_stop(struct seq_file
*seq
, void *v
)
899 static int memtype_seq_show(struct seq_file
*seq
, void *v
)
901 struct memtype
*print_entry
= (struct memtype
*)v
;
903 seq_printf(seq
, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry
->type
),
904 print_entry
->start
, print_entry
->end
);
910 static struct seq_operations memtype_seq_ops
= {
911 .start
= memtype_seq_start
,
912 .next
= memtype_seq_next
,
913 .stop
= memtype_seq_stop
,
914 .show
= memtype_seq_show
,
917 static int memtype_seq_open(struct inode
*inode
, struct file
*file
)
919 return seq_open(file
, &memtype_seq_ops
);
922 static const struct file_operations memtype_fops
= {
923 .open
= memtype_seq_open
,
926 .release
= seq_release
,
929 static int __init
pat_memtype_list_init(void)
931 debugfs_create_file("pat_memtype_list", S_IRUSR
, arch_debugfs_dir
,
932 NULL
, &memtype_fops
);
936 late_initcall(pat_memtype_list_init
);
938 #endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */