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(const 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
);
46 static inline void pat_disable(const char *reason
)
53 static int debug_enable
;
55 static int __init
pat_debug_setup(char *str
)
60 __setup("debugpat", pat_debug_setup
);
62 #define dprintk(fmt, arg...) \
63 do { if (debug_enable) printk(KERN_INFO fmt, ##arg); } while (0)
66 static u64 __read_mostly boot_pat_state
;
69 PAT_UC
= 0, /* uncached */
70 PAT_WC
= 1, /* Write combining */
71 PAT_WT
= 4, /* Write Through */
72 PAT_WP
= 5, /* Write Protected */
73 PAT_WB
= 6, /* Write Back (default) */
74 PAT_UC_MINUS
= 7, /* UC, but can be overriden by MTRR */
77 #define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
87 if (!boot_pat_state
) {
88 pat_disable("PAT not supported by CPU.");
92 * If this happens we are on a secondary CPU, but
93 * switched to PAT on the boot CPU. We have no way to
96 printk(KERN_ERR
"PAT enabled, "
97 "but not supported by secondary CPU\n");
102 /* Set PWT to Write-Combining. All other bits stay the same */
104 * PTE encoding used in Linux:
109 * 000 WB _PAGE_CACHE_WB
110 * 001 WC _PAGE_CACHE_WC
111 * 010 UC- _PAGE_CACHE_UC_MINUS
112 * 011 UC _PAGE_CACHE_UC
115 pat
= PAT(0, WB
) | PAT(1, WC
) | PAT(2, UC_MINUS
) | PAT(3, UC
) |
116 PAT(4, WB
) | PAT(5, WC
) | PAT(6, UC_MINUS
) | PAT(7, UC
);
120 rdmsrl(MSR_IA32_CR_PAT
, boot_pat_state
);
122 wrmsrl(MSR_IA32_CR_PAT
, pat
);
123 printk(KERN_INFO
"x86 PAT enabled: cpu %d, old 0x%Lx, new 0x%Lx\n",
124 smp_processor_id(), boot_pat_state
, pat
);
129 static char *cattr_name(unsigned long flags
)
131 switch (flags
& _PAGE_CACHE_MASK
) {
132 case _PAGE_CACHE_UC
: return "uncached";
133 case _PAGE_CACHE_UC_MINUS
: return "uncached-minus";
134 case _PAGE_CACHE_WB
: return "write-back";
135 case _PAGE_CACHE_WC
: return "write-combining";
136 default: return "broken";
141 * The global memtype list keeps track of memory type for specific
142 * physical memory areas. Conflicting memory types in different
143 * mappings can cause CPU cache corruption. To avoid this we keep track.
145 * The list is sorted based on starting address and can contain multiple
146 * entries for each address (this allows reference counting for overlapping
147 * areas). All the aliases have the same cache attributes of course.
148 * Zero attributes are represented as holes.
150 * Currently the data structure is a list because the number of mappings
151 * are expected to be relatively small. If this should be a problem
152 * it could be changed to a rbtree or similar.
154 * memtype_lock protects the whole list.
164 static LIST_HEAD(memtype_list
);
165 static DEFINE_SPINLOCK(memtype_lock
); /* protects memtype list */
168 * Does intersection of PAT memory type and MTRR memory type and returns
169 * the resulting memory type as PAT understands it.
170 * (Type in pat and mtrr will not have same value)
171 * The intersection is based on "Effective Memory Type" tables in IA-32
174 static unsigned long pat_x_mtrr_type(u64 start
, u64 end
, unsigned long req_type
)
177 * Look for MTRR hint to get the effective type in case where PAT
180 if (req_type
== _PAGE_CACHE_WB
) {
183 mtrr_type
= mtrr_type_lookup(start
, end
);
184 if (mtrr_type
== MTRR_TYPE_UNCACHABLE
)
185 return _PAGE_CACHE_UC
;
186 if (mtrr_type
== MTRR_TYPE_WRCOMB
)
187 return _PAGE_CACHE_WC
;
194 chk_conflict(struct memtype
*new, struct memtype
*entry
, unsigned long *type
)
196 if (new->type
!= entry
->type
) {
198 new->type
= entry
->type
;
204 /* check overlaps with more than one entry in the list */
205 list_for_each_entry_continue(entry
, &memtype_list
, nd
) {
206 if (new->end
<= entry
->start
)
208 else if (new->type
!= entry
->type
)
214 printk(KERN_INFO
"%s:%d conflicting memory types "
215 "%Lx-%Lx %s<->%s\n", current
->comm
, current
->pid
, new->start
,
216 new->end
, cattr_name(new->type
), cattr_name(entry
->type
));
220 static struct memtype
*cached_entry
;
221 static u64 cached_start
;
223 static int pat_pagerange_is_ram(unsigned long start
, unsigned long end
)
225 int ram_page
= 0, not_rampage
= 0;
226 unsigned long page_nr
;
228 for (page_nr
= (start
>> PAGE_SHIFT
); page_nr
< (end
>> PAGE_SHIFT
);
231 * For legacy reasons, physical address range in the legacy ISA
232 * region is tracked as non-RAM. This will allow users of
233 * /dev/mem to map portions of legacy ISA region, even when
234 * some of those portions are listed(or not even listed) with
235 * different e820 types(RAM/reserved/..)
237 if (page_nr
>= (ISA_END_ADDRESS
>> PAGE_SHIFT
) &&
238 page_is_ram(page_nr
))
243 if (ram_page
== not_rampage
)
251 * For RAM pages, mark the pages as non WB memory type using
252 * PageNonWB (PG_arch_1). We allow only one set_memory_uc() or
253 * set_memory_wc() on a RAM page at a time before marking it as WB again.
254 * This is ok, because only one driver will be owning the page and
255 * doing set_memory_*() calls.
257 * For now, we use PageNonWB to track that the RAM page is being mapped
258 * as non WB. In future, we will have to use one more flag
259 * (or some other mechanism in page_struct) to distinguish between
262 static int reserve_ram_pages_type(u64 start
, u64 end
, unsigned long req_type
,
263 unsigned long *new_type
)
268 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< (end
>> PAGE_SHIFT
); ++pfn
) {
269 page
= pfn_to_page(pfn
);
270 if (page_mapped(page
) || PageNonWB(page
))
279 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< end_pfn
; ++pfn
) {
280 page
= pfn_to_page(pfn
);
281 ClearPageNonWB(page
);
287 static int free_ram_pages_type(u64 start
, u64 end
)
292 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< (end
>> PAGE_SHIFT
); ++pfn
) {
293 page
= pfn_to_page(pfn
);
294 if (page_mapped(page
) || !PageNonWB(page
))
297 ClearPageNonWB(page
);
303 for (pfn
= (start
>> PAGE_SHIFT
); pfn
< end_pfn
; ++pfn
) {
304 page
= pfn_to_page(pfn
);
311 * req_type typically has one of the:
314 * - _PAGE_CACHE_UC_MINUS
317 * req_type will have a special case value '-1', when requester want to inherit
318 * the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
320 * If new_type is NULL, function will return an error if it cannot reserve the
321 * region with req_type. If new_type is non-NULL, function will return
322 * available type in new_type in case of no error. In case of any error
323 * it will return a negative return value.
325 int reserve_memtype(u64 start
, u64 end
, unsigned long req_type
,
326 unsigned long *new_type
)
328 struct memtype
*new, *entry
;
329 unsigned long actual_type
;
330 struct list_head
*where
;
334 BUG_ON(start
>= end
); /* end is exclusive */
337 /* This is identical to page table setting without PAT */
340 *new_type
= _PAGE_CACHE_WB
;
342 *new_type
= req_type
& _PAGE_CACHE_MASK
;
347 /* Low ISA region is always mapped WB in page table. No need to track */
348 if (is_ISA_range(start
, end
- 1)) {
350 *new_type
= _PAGE_CACHE_WB
;
354 if (req_type
== -1) {
356 * Call mtrr_lookup to get the type hint. This is an
357 * optimization for /dev/mem mmap'ers into WB memory (BIOS
358 * tools and ACPI tools). Use WB request for WB memory and use
359 * UC_MINUS otherwise.
361 u8 mtrr_type
= mtrr_type_lookup(start
, end
);
363 if (mtrr_type
== MTRR_TYPE_WRBACK
)
364 actual_type
= _PAGE_CACHE_WB
;
366 actual_type
= _PAGE_CACHE_UC_MINUS
;
368 actual_type
= pat_x_mtrr_type(start
, end
,
369 req_type
& _PAGE_CACHE_MASK
);
373 *new_type
= actual_type
;
375 is_range_ram
= pat_pagerange_is_ram(start
, end
);
376 if (is_range_ram
== 1)
377 return reserve_ram_pages_type(start
, end
, req_type
,
379 else if (is_range_ram
< 0)
382 new = kmalloc(sizeof(struct memtype
), GFP_KERNEL
);
388 new->type
= actual_type
;
390 spin_lock(&memtype_lock
);
392 if (cached_entry
&& start
>= cached_start
)
393 entry
= cached_entry
;
395 entry
= list_entry(&memtype_list
, struct memtype
, nd
);
397 /* Search for existing mapping that overlaps the current range */
399 list_for_each_entry_continue(entry
, &memtype_list
, nd
) {
400 if (end
<= entry
->start
) {
401 where
= entry
->nd
.prev
;
402 cached_entry
= list_entry(where
, struct memtype
, nd
);
404 } else if (start
<= entry
->start
) { /* end > entry->start */
405 err
= chk_conflict(new, entry
, new_type
);
407 dprintk("Overlap at 0x%Lx-0x%Lx\n",
408 entry
->start
, entry
->end
);
409 where
= entry
->nd
.prev
;
410 cached_entry
= list_entry(where
,
414 } else if (start
< entry
->end
) { /* start > entry->start */
415 err
= chk_conflict(new, entry
, new_type
);
417 dprintk("Overlap at 0x%Lx-0x%Lx\n",
418 entry
->start
, entry
->end
);
419 cached_entry
= list_entry(entry
->nd
.prev
,
423 * Move to right position in the linked
424 * list to add this new entry
426 list_for_each_entry_continue(entry
,
428 if (start
<= entry
->start
) {
429 where
= entry
->nd
.prev
;
439 printk(KERN_INFO
"reserve_memtype failed 0x%Lx-0x%Lx, "
440 "track %s, req %s\n",
441 start
, end
, cattr_name(new->type
), cattr_name(req_type
));
443 spin_unlock(&memtype_lock
);
448 cached_start
= start
;
451 list_add(&new->nd
, where
);
453 list_add_tail(&new->nd
, &memtype_list
);
455 spin_unlock(&memtype_lock
);
457 dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
458 start
, end
, cattr_name(new->type
), cattr_name(req_type
),
459 new_type
? cattr_name(*new_type
) : "-");
464 int free_memtype(u64 start
, u64 end
)
466 struct memtype
*entry
;
473 /* Low ISA region is always mapped WB. No need to track */
474 if (is_ISA_range(start
, end
- 1))
477 is_range_ram
= pat_pagerange_is_ram(start
, end
);
478 if (is_range_ram
== 1)
479 return free_ram_pages_type(start
, end
);
480 else if (is_range_ram
< 0)
483 spin_lock(&memtype_lock
);
484 list_for_each_entry(entry
, &memtype_list
, nd
) {
485 if (entry
->start
== start
&& entry
->end
== end
) {
486 if (cached_entry
== entry
|| cached_start
== start
)
489 list_del(&entry
->nd
);
495 spin_unlock(&memtype_lock
);
498 printk(KERN_INFO
"%s:%d freeing invalid memtype %Lx-%Lx\n",
499 current
->comm
, current
->pid
, start
, end
);
502 dprintk("free_memtype request 0x%Lx-0x%Lx\n", start
, end
);
508 pgprot_t
phys_mem_access_prot(struct file
*file
, unsigned long pfn
,
509 unsigned long size
, pgprot_t vma_prot
)
514 #ifdef CONFIG_STRICT_DEVMEM
515 /* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/
516 static inline int range_is_allowed(unsigned long pfn
, unsigned long size
)
521 /* This check is needed to avoid cache aliasing when PAT is enabled */
522 static inline int range_is_allowed(unsigned long pfn
, unsigned long size
)
524 u64 from
= ((u64
)pfn
) << PAGE_SHIFT
;
525 u64 to
= from
+ size
;
531 while (cursor
< to
) {
532 if (!devmem_is_allowed(pfn
)) {
534 "Program %s tried to access /dev/mem between %Lx->%Lx.\n",
535 current
->comm
, from
, to
);
543 #endif /* CONFIG_STRICT_DEVMEM */
545 int phys_mem_access_prot_allowed(struct file
*file
, unsigned long pfn
,
546 unsigned long size
, pgprot_t
*vma_prot
)
548 u64 offset
= ((u64
) pfn
) << PAGE_SHIFT
;
549 unsigned long flags
= -1;
552 if (!range_is_allowed(pfn
, size
))
555 if (file
->f_flags
& O_SYNC
) {
556 flags
= _PAGE_CACHE_UC_MINUS
;
561 * On the PPro and successors, the MTRRs are used to set
562 * memory types for physical addresses outside main memory,
563 * so blindly setting UC or PWT on those pages is wrong.
564 * For Pentiums and earlier, the surround logic should disable
565 * caching for the high addresses through the KEN pin, but
566 * we maintain the tradition of paranoia in this code.
569 !(boot_cpu_has(X86_FEATURE_MTRR
) ||
570 boot_cpu_has(X86_FEATURE_K6_MTRR
) ||
571 boot_cpu_has(X86_FEATURE_CYRIX_ARR
) ||
572 boot_cpu_has(X86_FEATURE_CENTAUR_MCR
)) &&
573 (pfn
<< PAGE_SHIFT
) >= __pa(high_memory
)) {
574 flags
= _PAGE_CACHE_UC
;
579 * With O_SYNC, we can only take UC_MINUS mapping. Fail if we cannot.
581 * Without O_SYNC, we want to get
582 * - WB for WB-able memory and no other conflicting mappings
583 * - UC_MINUS for non-WB-able memory with no other conflicting mappings
584 * - Inherit from confliting mappings otherwise
587 retval
= reserve_memtype(offset
, offset
+ size
, flags
, NULL
);
589 retval
= reserve_memtype(offset
, offset
+ size
, -1, &flags
);
595 if (((pfn
< max_low_pfn_mapped
) ||
596 (pfn
>= (1UL<<(32 - PAGE_SHIFT
)) && pfn
< max_pfn_mapped
)) &&
597 ioremap_change_attr((unsigned long)__va(offset
), size
, flags
) < 0) {
598 free_memtype(offset
, offset
+ size
);
600 "%s:%d /dev/mem ioremap_change_attr failed %s for %Lx-%Lx\n",
601 current
->comm
, current
->pid
,
603 offset
, (unsigned long long)(offset
+ size
));
607 *vma_prot
= __pgprot((pgprot_val(*vma_prot
) & ~_PAGE_CACHE_MASK
) |
612 void map_devmem(unsigned long pfn
, unsigned long size
, pgprot_t vma_prot
)
614 unsigned long want_flags
= (pgprot_val(vma_prot
) & _PAGE_CACHE_MASK
);
615 u64 addr
= (u64
)pfn
<< PAGE_SHIFT
;
618 reserve_memtype(addr
, addr
+ size
, want_flags
, &flags
);
619 if (flags
!= want_flags
) {
621 "%s:%d /dev/mem expected mapping type %s for %Lx-%Lx, got %s\n",
622 current
->comm
, current
->pid
,
623 cattr_name(want_flags
),
624 addr
, (unsigned long long)(addr
+ size
),
629 void unmap_devmem(unsigned long pfn
, unsigned long size
, pgprot_t vma_prot
)
631 u64 addr
= (u64
)pfn
<< PAGE_SHIFT
;
633 free_memtype(addr
, addr
+ size
);
637 * Internal interface to reserve a range of physical memory with prot.
638 * Reserved non RAM regions only and after successful reserve_memtype,
639 * this func also keeps identity mapping (if any) in sync with this new prot.
641 static int reserve_pfn_range(u64 paddr
, unsigned long size
, pgprot_t
*vma_prot
,
647 unsigned long want_flags
= (pgprot_val(*vma_prot
) & _PAGE_CACHE_MASK
);
649 is_ram
= pat_pagerange_is_ram(paddr
, paddr
+ size
);
652 * reserve_pfn_range() doesn't support RAM pages.
657 ret
= reserve_memtype(paddr
, paddr
+ size
, want_flags
, &flags
);
661 if (flags
!= want_flags
) {
662 if (strict_prot
|| !is_new_memtype_allowed(want_flags
, flags
)) {
663 free_memtype(paddr
, paddr
+ size
);
664 printk(KERN_ERR
"%s:%d map pfn expected mapping type %s"
665 " for %Lx-%Lx, got %s\n",
666 current
->comm
, current
->pid
,
667 cattr_name(want_flags
),
668 (unsigned long long)paddr
,
669 (unsigned long long)(paddr
+ size
),
674 * We allow returning different type than the one requested in
677 *vma_prot
= __pgprot((pgprot_val(*vma_prot
) &
678 (~_PAGE_CACHE_MASK
)) |
682 /* Need to keep identity mapping in sync */
683 if (paddr
>= __pa(high_memory
))
686 id_sz
= (__pa(high_memory
) < paddr
+ size
) ?
687 __pa(high_memory
) - paddr
:
690 if (ioremap_change_attr((unsigned long)__va(paddr
), id_sz
, flags
) < 0) {
691 free_memtype(paddr
, paddr
+ size
);
693 "%s:%d reserve_pfn_range ioremap_change_attr failed %s "
695 current
->comm
, current
->pid
,
697 (unsigned long long)paddr
,
698 (unsigned long long)(paddr
+ size
));
705 * Internal interface to free a range of physical memory.
706 * Frees non RAM regions only.
708 static void free_pfn_range(u64 paddr
, unsigned long size
)
712 is_ram
= pat_pagerange_is_ram(paddr
, paddr
+ size
);
714 free_memtype(paddr
, paddr
+ size
);
718 * track_pfn_vma_copy is called when vma that is covering the pfnmap gets
719 * copied through copy_page_range().
721 * If the vma has a linear pfn mapping for the entire range, we get the prot
722 * from pte and reserve the entire vma range with single reserve_pfn_range call.
723 * Otherwise, we reserve the entire vma range, my ging through the PTEs page
724 * by page to get physical address and protection.
726 int track_pfn_vma_copy(struct vm_area_struct
*vma
)
730 resource_size_t paddr
;
732 unsigned long vma_start
= vma
->vm_start
;
733 unsigned long vma_end
= vma
->vm_end
;
734 unsigned long vma_size
= vma_end
- vma_start
;
740 if (is_linear_pfn_mapping(vma
)) {
742 * reserve the whole chunk covered by vma. We need the
743 * starting address and protection from pte.
745 if (follow_phys(vma
, vma_start
, 0, &prot
, &paddr
)) {
749 pgprot
= __pgprot(prot
);
750 return reserve_pfn_range(paddr
, vma_size
, &pgprot
, 1);
753 /* reserve entire vma page by page, using pfn and prot from pte */
754 for (i
= 0; i
< vma_size
; i
+= PAGE_SIZE
) {
755 if (follow_phys(vma
, vma_start
+ i
, 0, &prot
, &paddr
))
758 pgprot
= __pgprot(prot
);
759 retval
= reserve_pfn_range(paddr
, PAGE_SIZE
, &pgprot
, 1);
766 /* Reserve error: Cleanup partial reservation and return error */
767 for (j
= 0; j
< i
; j
+= PAGE_SIZE
) {
768 if (follow_phys(vma
, vma_start
+ j
, 0, &prot
, &paddr
))
771 free_pfn_range(paddr
, PAGE_SIZE
);
778 * track_pfn_vma_new is called when a _new_ pfn mapping is being established
779 * for physical range indicated by pfn and size.
781 * prot is passed in as a parameter for the new mapping. If the vma has a
782 * linear pfn mapping for the entire range reserve the entire vma range with
783 * single reserve_pfn_range call.
784 * Otherwise, we look t the pfn and size and reserve only the specified range
787 * Note that this function can be called with caller trying to map only a
788 * subrange/page inside the vma.
790 int track_pfn_vma_new(struct vm_area_struct
*vma
, pgprot_t
*prot
,
791 unsigned long pfn
, unsigned long size
)
795 resource_size_t base_paddr
;
796 resource_size_t paddr
;
797 unsigned long vma_start
= vma
->vm_start
;
798 unsigned long vma_end
= vma
->vm_end
;
799 unsigned long vma_size
= vma_end
- vma_start
;
804 if (is_linear_pfn_mapping(vma
)) {
805 /* reserve the whole chunk starting from vm_pgoff */
806 paddr
= (resource_size_t
)vma
->vm_pgoff
<< PAGE_SHIFT
;
807 return reserve_pfn_range(paddr
, vma_size
, prot
, 0);
810 /* reserve page by page using pfn and size */
811 base_paddr
= (resource_size_t
)pfn
<< PAGE_SHIFT
;
812 for (i
= 0; i
< size
; i
+= PAGE_SIZE
) {
813 paddr
= base_paddr
+ i
;
814 retval
= reserve_pfn_range(paddr
, PAGE_SIZE
, prot
, 0);
821 /* Reserve error: Cleanup partial reservation and return error */
822 for (j
= 0; j
< i
; j
+= PAGE_SIZE
) {
823 paddr
= base_paddr
+ j
;
824 free_pfn_range(paddr
, PAGE_SIZE
);
831 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
832 * untrack can be called for a specific region indicated by pfn and size or
833 * can be for the entire vma (in which case size can be zero).
835 void untrack_pfn_vma(struct vm_area_struct
*vma
, unsigned long pfn
,
839 resource_size_t paddr
;
841 unsigned long vma_start
= vma
->vm_start
;
842 unsigned long vma_end
= vma
->vm_end
;
843 unsigned long vma_size
= vma_end
- vma_start
;
848 if (is_linear_pfn_mapping(vma
)) {
849 /* free the whole chunk starting from vm_pgoff */
850 paddr
= (resource_size_t
)vma
->vm_pgoff
<< PAGE_SHIFT
;
851 free_pfn_range(paddr
, vma_size
);
855 if (size
!= 0 && size
!= vma_size
) {
856 /* free page by page, using pfn and size */
857 paddr
= (resource_size_t
)pfn
<< PAGE_SHIFT
;
858 for (i
= 0; i
< size
; i
+= PAGE_SIZE
) {
860 free_pfn_range(paddr
, PAGE_SIZE
);
863 /* free entire vma, page by page, using the pfn from pte */
864 for (i
= 0; i
< vma_size
; i
+= PAGE_SIZE
) {
865 if (follow_phys(vma
, vma_start
+ i
, 0, &prot
, &paddr
))
868 free_pfn_range(paddr
, PAGE_SIZE
);
873 pgprot_t
pgprot_writecombine(pgprot_t prot
)
876 return __pgprot(pgprot_val(prot
) | _PAGE_CACHE_WC
);
878 return pgprot_noncached(prot
);
881 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
883 /* get Nth element of the linked list */
884 static struct memtype
*memtype_get_idx(loff_t pos
)
886 struct memtype
*list_node
, *print_entry
;
889 print_entry
= kmalloc(sizeof(struct memtype
), GFP_KERNEL
);
893 spin_lock(&memtype_lock
);
894 list_for_each_entry(list_node
, &memtype_list
, nd
) {
896 *print_entry
= *list_node
;
897 spin_unlock(&memtype_lock
);
902 spin_unlock(&memtype_lock
);
908 static void *memtype_seq_start(struct seq_file
*seq
, loff_t
*pos
)
912 seq_printf(seq
, "PAT memtype list:\n");
915 return memtype_get_idx(*pos
);
918 static void *memtype_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
921 return memtype_get_idx(*pos
);
924 static void memtype_seq_stop(struct seq_file
*seq
, void *v
)
928 static int memtype_seq_show(struct seq_file
*seq
, void *v
)
930 struct memtype
*print_entry
= (struct memtype
*)v
;
932 seq_printf(seq
, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry
->type
),
933 print_entry
->start
, print_entry
->end
);
939 static struct seq_operations memtype_seq_ops
= {
940 .start
= memtype_seq_start
,
941 .next
= memtype_seq_next
,
942 .stop
= memtype_seq_stop
,
943 .show
= memtype_seq_show
,
946 static int memtype_seq_open(struct inode
*inode
, struct file
*file
)
948 return seq_open(file
, &memtype_seq_ops
);
951 static const struct file_operations memtype_fops
= {
952 .open
= memtype_seq_open
,
955 .release
= seq_release
,
958 static int __init
pat_memtype_list_init(void)
960 debugfs_create_file("pat_memtype_list", S_IRUSR
, arch_debugfs_dir
,
961 NULL
, &memtype_fops
);
965 late_initcall(pat_memtype_list_init
);
967 #endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */