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https://github.com/torvalds/linux
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Merge branch 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, pat: Update the page flags for memtype atomically instead of using memtype_lock x86, pat: In rbt_memtype_check_insert(), update new->type only if valid x86, pat: Migrate to rbtree only backend for pat memtype management x86, pat: Preparatory changes in pat.c for bigger rbtree change rbtree: Add support for augmented rbtrees
This commit is contained in:
Linus Torvalds
commit
c4fd308ed6
8 changed files with 470 additions and 244 deletions
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@ -190,3 +190,61 @@ Example:
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for (node = rb_first(&mytree); node; node = rb_next(node))
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printk("key=%s\n", rb_entry(node, struct mytype, node)->keystring);
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Support for Augmented rbtrees
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-----------------------------
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Augmented rbtree is an rbtree with "some" additional data stored in each node.
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This data can be used to augment some new functionality to rbtree.
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Augmented rbtree is an optional feature built on top of basic rbtree
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infrastructure. rbtree user who wants this feature will have an augment
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callback function in rb_root initialized.
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This callback function will be called from rbtree core routines whenever
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a node has a change in one or both of its children. It is the responsibility
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of the callback function to recalculate the additional data that is in the
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rb node using new children information. Note that if this new additional
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data affects the parent node's additional data, then callback function has
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to handle it and do the recursive updates.
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Interval tree is an example of augmented rb tree. Reference -
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"Introduction to Algorithms" by Cormen, Leiserson, Rivest and Stein.
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More details about interval trees:
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Classical rbtree has a single key and it cannot be directly used to store
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interval ranges like [lo:hi] and do a quick lookup for any overlap with a new
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lo:hi or to find whether there is an exact match for a new lo:hi.
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However, rbtree can be augmented to store such interval ranges in a structured
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way making it possible to do efficient lookup and exact match.
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This "extra information" stored in each node is the maximum hi
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(max_hi) value among all the nodes that are its descendents. This
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information can be maintained at each node just be looking at the node
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and its immediate children. And this will be used in O(log n) lookup
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for lowest match (lowest start address among all possible matches)
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with something like:
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find_lowest_match(lo, hi, node)
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{
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lowest_match = NULL;
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while (node) {
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if (max_hi(node->left) > lo) {
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// Lowest overlap if any must be on left side
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node = node->left;
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} else if (overlap(lo, hi, node)) {
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lowest_match = node;
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break;
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} else if (lo > node->lo) {
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// Lowest overlap if any must be on right side
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node = node->right;
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} else {
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break;
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}
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}
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return lowest_match;
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}
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Finding exact match will be to first find lowest match and then to follow
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successor nodes looking for exact match, until the start of a node is beyond
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the hi value we are looking for.
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@ -44,9 +44,6 @@ static inline void copy_from_user_page(struct vm_area_struct *vma,
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memcpy(dst, src, len);
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}
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#define PG_WC PG_arch_1
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PAGEFLAG(WC, WC)
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#ifdef CONFIG_X86_PAT
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/*
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* X86 PAT uses page flags WC and Uncached together to keep track of
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@ -55,16 +52,24 @@ PAGEFLAG(WC, WC)
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* _PAGE_CACHE_UC_MINUS and fourth state where page's memory type has not
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* been changed from its default (value of -1 used to denote this).
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* Note we do not support _PAGE_CACHE_UC here.
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*
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* Caller must hold memtype_lock for atomicity.
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*/
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#define _PGMT_DEFAULT 0
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#define _PGMT_WC (1UL << PG_arch_1)
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#define _PGMT_UC_MINUS (1UL << PG_uncached)
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#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1)
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#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
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#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
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static inline unsigned long get_page_memtype(struct page *pg)
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{
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if (!PageUncached(pg) && !PageWC(pg))
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unsigned long pg_flags = pg->flags & _PGMT_MASK;
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if (pg_flags == _PGMT_DEFAULT)
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return -1;
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else if (!PageUncached(pg) && PageWC(pg))
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else if (pg_flags == _PGMT_WC)
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return _PAGE_CACHE_WC;
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else if (PageUncached(pg) && !PageWC(pg))
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else if (pg_flags == _PGMT_UC_MINUS)
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return _PAGE_CACHE_UC_MINUS;
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else
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return _PAGE_CACHE_WB;
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@ -72,25 +77,26 @@ static inline unsigned long get_page_memtype(struct page *pg)
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static inline void set_page_memtype(struct page *pg, unsigned long memtype)
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{
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unsigned long memtype_flags = _PGMT_DEFAULT;
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unsigned long old_flags;
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unsigned long new_flags;
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switch (memtype) {
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case _PAGE_CACHE_WC:
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ClearPageUncached(pg);
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SetPageWC(pg);
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memtype_flags = _PGMT_WC;
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break;
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case _PAGE_CACHE_UC_MINUS:
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SetPageUncached(pg);
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ClearPageWC(pg);
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memtype_flags = _PGMT_UC_MINUS;
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break;
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case _PAGE_CACHE_WB:
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SetPageUncached(pg);
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SetPageWC(pg);
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break;
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default:
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case -1:
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ClearPageUncached(pg);
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ClearPageWC(pg);
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memtype_flags = _PGMT_WB;
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break;
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}
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do {
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old_flags = pg->flags;
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new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
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} while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
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}
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#else
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static inline unsigned long get_page_memtype(struct page *pg) { return -1; }
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@ -6,6 +6,7 @@ nostackp := $(call cc-option, -fno-stack-protector)
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CFLAGS_physaddr.o := $(nostackp)
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CFLAGS_setup_nx.o := $(nostackp)
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obj-$(CONFIG_X86_PAT) += pat_rbtree.o
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obj-$(CONFIG_SMP) += tlb.o
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obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o
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@ -30,6 +30,8 @@
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#include <asm/pat.h>
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#include <asm/io.h>
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#include "pat_internal.h"
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#ifdef CONFIG_X86_PAT
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int __read_mostly pat_enabled = 1;
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@ -53,19 +55,15 @@ static inline void pat_disable(const char *reason)
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#endif
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static int debug_enable;
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int pat_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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pat_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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@ -132,84 +130,7 @@ void pat_init(void)
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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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* The data structure is a list that is also organized as an rbtree
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* sorted on the start address of memtype range.
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*
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* memtype_lock protects both the linear list and rbtree.
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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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struct rb_node rb;
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};
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static struct rb_root memtype_rbroot = RB_ROOT;
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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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static struct memtype *memtype_rb_search(struct rb_root *root, u64 start)
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{
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struct rb_node *node = root->rb_node;
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struct memtype *last_lower = NULL;
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while (node) {
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struct memtype *data = container_of(node, struct memtype, rb);
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if (data->start < start) {
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last_lower = data;
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node = node->rb_right;
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} else if (data->start > start) {
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node = node->rb_left;
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} else
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return data;
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}
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/* Will return NULL if there is no entry with its start <= start */
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return last_lower;
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}
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static void memtype_rb_insert(struct rb_root *root, struct memtype *data)
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{
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struct rb_node **new = &(root->rb_node);
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struct rb_node *parent = NULL;
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while (*new) {
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struct memtype *this = container_of(*new, struct memtype, rb);
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parent = *new;
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if (data->start <= this->start)
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new = &((*new)->rb_left);
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else if (data->start > this->start)
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new = &((*new)->rb_right);
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}
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rb_link_node(&data->rb, parent, new);
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rb_insert_color(&data->rb, root);
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}
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static DEFINE_SPINLOCK(memtype_lock); /* protects memtype accesses */
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/*
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* Does intersection of PAT memory type and MTRR memory type and returns
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|
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@ -237,33 +158,6 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
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return req_type;
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}
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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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|
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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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}
|
||||
|
||||
static int pat_pagerange_is_ram(unsigned long start, unsigned long end)
|
||||
{
|
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int ram_page = 0, not_rampage = 0;
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|
|
@ -296,8 +190,6 @@ static int pat_pagerange_is_ram(unsigned long start, unsigned long end)
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|||
* Here we do two pass:
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||||
* - Find the memtype of all the pages in the range, look for any conflicts
|
||||
* - In case of no conflicts, set the new memtype for pages in the range
|
||||
*
|
||||
* Caller must hold memtype_lock for atomicity.
|
||||
*/
|
||||
static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type,
|
||||
unsigned long *new_type)
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||||
|
|
@ -364,9 +256,8 @@ static int free_ram_pages_type(u64 start, u64 end)
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|||
int reserve_memtype(u64 start, u64 end, unsigned long req_type,
|
||||
unsigned long *new_type)
|
||||
{
|
||||
struct memtype *new, *entry;
|
||||
struct memtype *new;
|
||||
unsigned long actual_type;
|
||||
struct list_head *where;
|
||||
int is_range_ram;
|
||||
int err = 0;
|
||||
|
||||
|
|
@ -404,9 +295,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
|
|||
is_range_ram = pat_pagerange_is_ram(start, end);
|
||||
if (is_range_ram == 1) {
|
||||
|
||||
spin_lock(&memtype_lock);
|
||||
err = reserve_ram_pages_type(start, end, req_type, new_type);
|
||||
spin_unlock(&memtype_lock);
|
||||
|
||||
return err;
|
||||
} else if (is_range_ram < 0) {
|
||||
|
|
@ -423,42 +312,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
|
|||
|
||||
spin_lock(&memtype_lock);
|
||||
|
||||
/* Search for existing mapping that overlaps the current range */
|
||||
where = NULL;
|
||||
list_for_each_entry(entry, &memtype_list, nd) {
|
||||
if (end <= entry->start) {
|
||||
where = entry->nd.prev;
|
||||
break;
|
||||
} else if (start <= entry->start) { /* end > entry->start */
|
||||
err = chk_conflict(new, entry, new_type);
|
||||
if (!err) {
|
||||
dprintk("Overlap at 0x%Lx-0x%Lx\n",
|
||||
entry->start, entry->end);
|
||||
where = entry->nd.prev;
|
||||
}
|
||||
break;
|
||||
} else if (start < entry->end) { /* start > entry->start */
|
||||
err = chk_conflict(new, entry, new_type);
|
||||
if (!err) {
|
||||
dprintk("Overlap at 0x%Lx-0x%Lx\n",
|
||||
entry->start, entry->end);
|
||||
|
||||
/*
|
||||
* Move to right position in the linked
|
||||
* list to add this new entry
|
||||
*/
|
||||
list_for_each_entry_continue(entry,
|
||||
&memtype_list, nd) {
|
||||
if (start <= entry->start) {
|
||||
where = entry->nd.prev;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
err = rbt_memtype_check_insert(new, new_type);
|
||||
if (err) {
|
||||
printk(KERN_INFO "reserve_memtype failed 0x%Lx-0x%Lx, "
|
||||
"track %s, req %s\n",
|
||||
|
|
@ -469,13 +323,6 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
|
|||
return err;
|
||||
}
|
||||
|
||||
if (where)
|
||||
list_add(&new->nd, where);
|
||||
else
|
||||
list_add_tail(&new->nd, &memtype_list);
|
||||
|
||||
memtype_rb_insert(&memtype_rbroot, new);
|
||||
|
||||
spin_unlock(&memtype_lock);
|
||||
|
||||
dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
|
||||
|
|
@ -487,7 +334,6 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
|
|||
|
||||
int free_memtype(u64 start, u64 end)
|
||||
{
|
||||
struct memtype *entry, *saved_entry;
|
||||
int err = -EINVAL;
|
||||
int is_range_ram;
|
||||
|
||||
|
|
@ -501,9 +347,7 @@ int free_memtype(u64 start, u64 end)
|
|||
is_range_ram = pat_pagerange_is_ram(start, end);
|
||||
if (is_range_ram == 1) {
|
||||
|
||||
spin_lock(&memtype_lock);
|
||||
err = free_ram_pages_type(start, end);
|
||||
spin_unlock(&memtype_lock);
|
||||
|
||||
return err;
|
||||
} else if (is_range_ram < 0) {
|
||||
|
|
@ -511,46 +355,7 @@ int free_memtype(u64 start, u64 end)
|
|||
}
|
||||
|
||||
spin_lock(&memtype_lock);
|
||||
|
||||
entry = memtype_rb_search(&memtype_rbroot, start);
|
||||
if (unlikely(entry == NULL))
|
||||
goto unlock_ret;
|
||||
|
||||
/*
|
||||
* Saved entry points to an entry with start same or less than what
|
||||
* we searched for. Now go through the list in both directions to look
|
||||
* for the entry that matches with both start and end, with list stored
|
||||
* in sorted start address
|
||||
*/
|
||||
saved_entry = entry;
|
||||
list_for_each_entry_from(entry, &memtype_list, nd) {
|
||||
if (entry->start == start && entry->end == end) {
|
||||
rb_erase(&entry->rb, &memtype_rbroot);
|
||||
list_del(&entry->nd);
|
||||
kfree(entry);
|
||||
err = 0;
|
||||
break;
|
||||
} else if (entry->start > start) {
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (!err)
|
||||
goto unlock_ret;
|
||||
|
||||
entry = saved_entry;
|
||||
list_for_each_entry_reverse(entry, &memtype_list, nd) {
|
||||
if (entry->start == start && entry->end == end) {
|
||||
rb_erase(&entry->rb, &memtype_rbroot);
|
||||
list_del(&entry->nd);
|
||||
kfree(entry);
|
||||
err = 0;
|
||||
break;
|
||||
} else if (entry->start < start) {
|
||||
break;
|
||||
}
|
||||
}
|
||||
unlock_ret:
|
||||
err = rbt_memtype_erase(start, end);
|
||||
spin_unlock(&memtype_lock);
|
||||
|
||||
if (err) {
|
||||
|
|
@ -583,10 +388,8 @@ static unsigned long lookup_memtype(u64 paddr)
|
|||
|
||||
if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
|
||||
struct page *page;
|
||||
spin_lock(&memtype_lock);
|
||||
page = pfn_to_page(paddr >> PAGE_SHIFT);
|
||||
rettype = get_page_memtype(page);
|
||||
spin_unlock(&memtype_lock);
|
||||
/*
|
||||
* -1 from get_page_memtype() implies RAM page is in its
|
||||
* default state and not reserved, and hence of type WB
|
||||
|
|
@ -599,7 +402,7 @@ static unsigned long lookup_memtype(u64 paddr)
|
|||
|
||||
spin_lock(&memtype_lock);
|
||||
|
||||
entry = memtype_rb_search(&memtype_rbroot, paddr);
|
||||
entry = rbt_memtype_lookup(paddr);
|
||||
if (entry != NULL)
|
||||
rettype = entry->type;
|
||||
else
|
||||
|
|
@ -936,29 +739,25 @@ EXPORT_SYMBOL_GPL(pgprot_writecombine);
|
|||
|
||||
#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;
|
||||
struct memtype *print_entry;
|
||||
int ret;
|
||||
|
||||
print_entry = kmalloc(sizeof(struct memtype), GFP_KERNEL);
|
||||
print_entry = kzalloc(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;
|
||||
}
|
||||
ret = rbt_memtype_copy_nth_element(print_entry, pos);
|
||||
spin_unlock(&memtype_lock);
|
||||
kfree(print_entry);
|
||||
|
||||
return NULL;
|
||||
if (!ret) {
|
||||
return print_entry;
|
||||
} else {
|
||||
kfree(print_entry);
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
|
||||
static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
|
||||
|
|
|
|||
46
arch/x86/mm/pat_internal.h
Normal file
46
arch/x86/mm/pat_internal.h
Normal file
|
|
@ -0,0 +1,46 @@
|
|||
#ifndef __PAT_INTERNAL_H_
|
||||
#define __PAT_INTERNAL_H_
|
||||
|
||||
extern int pat_debug_enable;
|
||||
|
||||
#define dprintk(fmt, arg...) \
|
||||
do { if (pat_debug_enable) printk(KERN_INFO fmt, ##arg); } while (0)
|
||||
|
||||
struct memtype {
|
||||
u64 start;
|
||||
u64 end;
|
||||
u64 subtree_max_end;
|
||||
unsigned long type;
|
||||
struct rb_node rb;
|
||||
};
|
||||
|
||||
static inline char *cattr_name(unsigned long flags)
|
||||
{
|
||||
switch (flags & _PAGE_CACHE_MASK) {
|
||||
case _PAGE_CACHE_UC: return "uncached";
|
||||
case _PAGE_CACHE_UC_MINUS: return "uncached-minus";
|
||||
case _PAGE_CACHE_WB: return "write-back";
|
||||
case _PAGE_CACHE_WC: return "write-combining";
|
||||
default: return "broken";
|
||||
}
|
||||
}
|
||||
|
||||
#ifdef CONFIG_X86_PAT
|
||||
extern int rbt_memtype_check_insert(struct memtype *new,
|
||||
unsigned long *new_type);
|
||||
extern int rbt_memtype_erase(u64 start, u64 end);
|
||||
extern struct memtype *rbt_memtype_lookup(u64 addr);
|
||||
extern int rbt_memtype_copy_nth_element(struct memtype *out, loff_t pos);
|
||||
#else
|
||||
static inline int rbt_memtype_check_insert(struct memtype *new,
|
||||
unsigned long *new_type)
|
||||
{ return 0; }
|
||||
static inline int rbt_memtype_erase(u64 start, u64 end)
|
||||
{ return 0; }
|
||||
static inline struct memtype *rbt_memtype_lookup(u64 addr)
|
||||
{ return NULL; }
|
||||
static inline int rbt_memtype_copy_nth_element(struct memtype *out, loff_t pos)
|
||||
{ return 0; }
|
||||
#endif
|
||||
|
||||
#endif /* __PAT_INTERNAL_H_ */
|
||||
273
arch/x86/mm/pat_rbtree.c
Normal file
273
arch/x86/mm/pat_rbtree.c
Normal file
|
|
@ -0,0 +1,273 @@
|
|||
/*
|
||||
* Handle caching attributes in page tables (PAT)
|
||||
*
|
||||
* Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
|
||||
* Suresh B Siddha <suresh.b.siddha@intel.com>
|
||||
*
|
||||
* Interval tree (augmented rbtree) used to store the PAT memory type
|
||||
* reservations.
|
||||
*/
|
||||
|
||||
#include <linux/seq_file.h>
|
||||
#include <linux/debugfs.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/gfp.h>
|
||||
|
||||
#include <asm/pgtable.h>
|
||||
#include <asm/pat.h>
|
||||
|
||||
#include "pat_internal.h"
|
||||
|
||||
/*
|
||||
* The memtype tree keeps track of memory type for specific
|
||||
* physical memory areas. Without proper tracking, conflicting memory
|
||||
* types in different mappings can cause CPU cache corruption.
|
||||
*
|
||||
* The tree is an interval tree (augmented rbtree) with tree ordered
|
||||
* on starting address. Tree can contain multiple entries for
|
||||
* different regions which overlap. All the aliases have the same
|
||||
* cache attributes of course.
|
||||
*
|
||||
* memtype_lock protects the rbtree.
|
||||
*/
|
||||
|
||||
static void memtype_rb_augment_cb(struct rb_node *node);
|
||||
static struct rb_root memtype_rbroot = RB_AUGMENT_ROOT(&memtype_rb_augment_cb);
|
||||
|
||||
static int is_node_overlap(struct memtype *node, u64 start, u64 end)
|
||||
{
|
||||
if (node->start >= end || node->end <= start)
|
||||
return 0;
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static u64 get_subtree_max_end(struct rb_node *node)
|
||||
{
|
||||
u64 ret = 0;
|
||||
if (node) {
|
||||
struct memtype *data = container_of(node, struct memtype, rb);
|
||||
ret = data->subtree_max_end;
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Update 'subtree_max_end' for a node, based on node and its children */
|
||||
static void update_node_max_end(struct rb_node *node)
|
||||
{
|
||||
struct memtype *data;
|
||||
u64 max_end, child_max_end;
|
||||
|
||||
if (!node)
|
||||
return;
|
||||
|
||||
data = container_of(node, struct memtype, rb);
|
||||
max_end = data->end;
|
||||
|
||||
child_max_end = get_subtree_max_end(node->rb_right);
|
||||
if (child_max_end > max_end)
|
||||
max_end = child_max_end;
|
||||
|
||||
child_max_end = get_subtree_max_end(node->rb_left);
|
||||
if (child_max_end > max_end)
|
||||
max_end = child_max_end;
|
||||
|
||||
data->subtree_max_end = max_end;
|
||||
}
|
||||
|
||||
/* Update 'subtree_max_end' for a node and all its ancestors */
|
||||
static void update_path_max_end(struct rb_node *node)
|
||||
{
|
||||
u64 old_max_end, new_max_end;
|
||||
|
||||
while (node) {
|
||||
struct memtype *data = container_of(node, struct memtype, rb);
|
||||
|
||||
old_max_end = data->subtree_max_end;
|
||||
update_node_max_end(node);
|
||||
new_max_end = data->subtree_max_end;
|
||||
|
||||
if (new_max_end == old_max_end)
|
||||
break;
|
||||
|
||||
node = rb_parent(node);
|
||||
}
|
||||
}
|
||||
|
||||
/* Find the first (lowest start addr) overlapping range from rb tree */
|
||||
static struct memtype *memtype_rb_lowest_match(struct rb_root *root,
|
||||
u64 start, u64 end)
|
||||
{
|
||||
struct rb_node *node = root->rb_node;
|
||||
struct memtype *last_lower = NULL;
|
||||
|
||||
while (node) {
|
||||
struct memtype *data = container_of(node, struct memtype, rb);
|
||||
|
||||
if (get_subtree_max_end(node->rb_left) > start) {
|
||||
/* Lowest overlap if any must be on left side */
|
||||
node = node->rb_left;
|
||||
} else if (is_node_overlap(data, start, end)) {
|
||||
last_lower = data;
|
||||
break;
|
||||
} else if (start >= data->start) {
|
||||
/* Lowest overlap if any must be on right side */
|
||||
node = node->rb_right;
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
return last_lower; /* Returns NULL if there is no overlap */
|
||||
}
|
||||
|
||||
static struct memtype *memtype_rb_exact_match(struct rb_root *root,
|
||||
u64 start, u64 end)
|
||||
{
|
||||
struct memtype *match;
|
||||
|
||||
match = memtype_rb_lowest_match(root, start, end);
|
||||
while (match != NULL && match->start < end) {
|
||||
struct rb_node *node;
|
||||
|
||||
if (match->start == start && match->end == end)
|
||||
return match;
|
||||
|
||||
node = rb_next(&match->rb);
|
||||
if (node)
|
||||
match = container_of(node, struct memtype, rb);
|
||||
else
|
||||
match = NULL;
|
||||
}
|
||||
|
||||
return NULL; /* Returns NULL if there is no exact match */
|
||||
}
|
||||
|
||||
static int memtype_rb_check_conflict(struct rb_root *root,
|
||||
u64 start, u64 end,
|
||||
unsigned long reqtype, unsigned long *newtype)
|
||||
{
|
||||
struct rb_node *node;
|
||||
struct memtype *match;
|
||||
int found_type = reqtype;
|
||||
|
||||
match = memtype_rb_lowest_match(&memtype_rbroot, start, end);
|
||||
if (match == NULL)
|
||||
goto success;
|
||||
|
||||
if (match->type != found_type && newtype == NULL)
|
||||
goto failure;
|
||||
|
||||
dprintk("Overlap at 0x%Lx-0x%Lx\n", match->start, match->end);
|
||||
found_type = match->type;
|
||||
|
||||
node = rb_next(&match->rb);
|
||||
while (node) {
|
||||
match = container_of(node, struct memtype, rb);
|
||||
|
||||
if (match->start >= end) /* Checked all possible matches */
|
||||
goto success;
|
||||
|
||||
if (is_node_overlap(match, start, end) &&
|
||||
match->type != found_type) {
|
||||
goto failure;
|
||||
}
|
||||
|
||||
node = rb_next(&match->rb);
|
||||
}
|
||||
success:
|
||||
if (newtype)
|
||||
*newtype = found_type;
|
||||
|
||||
return 0;
|
||||
|
||||
failure:
|
||||
printk(KERN_INFO "%s:%d conflicting memory types "
|
||||
"%Lx-%Lx %s<->%s\n", current->comm, current->pid, start,
|
||||
end, cattr_name(found_type), cattr_name(match->type));
|
||||
return -EBUSY;
|
||||
}
|
||||
|
||||
static void memtype_rb_augment_cb(struct rb_node *node)
|
||||
{
|
||||
if (node)
|
||||
update_path_max_end(node);
|
||||
}
|
||||
|
||||
static void memtype_rb_insert(struct rb_root *root, struct memtype *newdata)
|
||||
{
|
||||
struct rb_node **node = &(root->rb_node);
|
||||
struct rb_node *parent = NULL;
|
||||
|
||||
while (*node) {
|
||||
struct memtype *data = container_of(*node, struct memtype, rb);
|
||||
|
||||
parent = *node;
|
||||
if (newdata->start <= data->start)
|
||||
node = &((*node)->rb_left);
|
||||
else if (newdata->start > data->start)
|
||||
node = &((*node)->rb_right);
|
||||
}
|
||||
|
||||
rb_link_node(&newdata->rb, parent, node);
|
||||
rb_insert_color(&newdata->rb, root);
|
||||
}
|
||||
|
||||
int rbt_memtype_check_insert(struct memtype *new, unsigned long *ret_type)
|
||||
{
|
||||
int err = 0;
|
||||
|
||||
err = memtype_rb_check_conflict(&memtype_rbroot, new->start, new->end,
|
||||
new->type, ret_type);
|
||||
|
||||
if (!err) {
|
||||
if (ret_type)
|
||||
new->type = *ret_type;
|
||||
|
||||
memtype_rb_insert(&memtype_rbroot, new);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
int rbt_memtype_erase(u64 start, u64 end)
|
||||
{
|
||||
struct memtype *data;
|
||||
|
||||
data = memtype_rb_exact_match(&memtype_rbroot, start, end);
|
||||
if (!data)
|
||||
return -EINVAL;
|
||||
|
||||
rb_erase(&data->rb, &memtype_rbroot);
|
||||
return 0;
|
||||
}
|
||||
|
||||
struct memtype *rbt_memtype_lookup(u64 addr)
|
||||
{
|
||||
struct memtype *data;
|
||||
data = memtype_rb_lowest_match(&memtype_rbroot, addr, addr + PAGE_SIZE);
|
||||
return data;
|
||||
}
|
||||
|
||||
#if defined(CONFIG_DEBUG_FS)
|
||||
int rbt_memtype_copy_nth_element(struct memtype *out, loff_t pos)
|
||||
{
|
||||
struct rb_node *node;
|
||||
int i = 1;
|
||||
|
||||
node = rb_first(&memtype_rbroot);
|
||||
while (node && pos != i) {
|
||||
node = rb_next(node);
|
||||
i++;
|
||||
}
|
||||
|
||||
if (node) { /* pos == i */
|
||||
struct memtype *this = container_of(node, struct memtype, rb);
|
||||
*out = *this;
|
||||
return 0;
|
||||
} else {
|
||||
return 1;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
|
@ -110,6 +110,7 @@ struct rb_node
|
|||
struct rb_root
|
||||
{
|
||||
struct rb_node *rb_node;
|
||||
void (*augment_cb)(struct rb_node *node);
|
||||
};
|
||||
|
||||
|
||||
|
|
@ -129,7 +130,9 @@ static inline void rb_set_color(struct rb_node *rb, int color)
|
|||
rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
|
||||
}
|
||||
|
||||
#define RB_ROOT (struct rb_root) { NULL, }
|
||||
#define RB_ROOT (struct rb_root) { NULL, NULL, }
|
||||
#define RB_AUGMENT_ROOT(x) (struct rb_root) { NULL, x}
|
||||
|
||||
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
|
||||
|
||||
#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
|
||||
|
|
|
|||
48
lib/rbtree.c
48
lib/rbtree.c
|
|
@ -44,6 +44,11 @@ static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
|
|||
else
|
||||
root->rb_node = right;
|
||||
rb_set_parent(node, right);
|
||||
|
||||
if (root->augment_cb) {
|
||||
root->augment_cb(node);
|
||||
root->augment_cb(right);
|
||||
}
|
||||
}
|
||||
|
||||
static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
|
||||
|
|
@ -67,12 +72,20 @@ static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
|
|||
else
|
||||
root->rb_node = left;
|
||||
rb_set_parent(node, left);
|
||||
|
||||
if (root->augment_cb) {
|
||||
root->augment_cb(node);
|
||||
root->augment_cb(left);
|
||||
}
|
||||
}
|
||||
|
||||
void rb_insert_color(struct rb_node *node, struct rb_root *root)
|
||||
{
|
||||
struct rb_node *parent, *gparent;
|
||||
|
||||
if (root->augment_cb)
|
||||
root->augment_cb(node);
|
||||
|
||||
while ((parent = rb_parent(node)) && rb_is_red(parent))
|
||||
{
|
||||
gparent = rb_parent(parent);
|
||||
|
|
@ -227,12 +240,15 @@ void rb_erase(struct rb_node *node, struct rb_root *root)
|
|||
else
|
||||
{
|
||||
struct rb_node *old = node, *left;
|
||||
int old_parent_cb = 0;
|
||||
int successor_parent_cb = 0;
|
||||
|
||||
node = node->rb_right;
|
||||
while ((left = node->rb_left) != NULL)
|
||||
node = left;
|
||||
|
||||
if (rb_parent(old)) {
|
||||
old_parent_cb = 1;
|
||||
if (rb_parent(old)->rb_left == old)
|
||||
rb_parent(old)->rb_left = node;
|
||||
else
|
||||
|
|
@ -247,8 +263,10 @@ void rb_erase(struct rb_node *node, struct rb_root *root)
|
|||
if (parent == old) {
|
||||
parent = node;
|
||||
} else {
|
||||
successor_parent_cb = 1;
|
||||
if (child)
|
||||
rb_set_parent(child, parent);
|
||||
|
||||
parent->rb_left = child;
|
||||
|
||||
node->rb_right = old->rb_right;
|
||||
|
|
@ -259,6 +277,24 @@ void rb_erase(struct rb_node *node, struct rb_root *root)
|
|||
node->rb_left = old->rb_left;
|
||||
rb_set_parent(old->rb_left, node);
|
||||
|
||||
if (root->augment_cb) {
|
||||
/*
|
||||
* Here, three different nodes can have new children.
|
||||
* The parent of the successor node that was selected
|
||||
* to replace the node to be erased.
|
||||
* The node that is getting erased and is now replaced
|
||||
* by its successor.
|
||||
* The parent of the node getting erased-replaced.
|
||||
*/
|
||||
if (successor_parent_cb)
|
||||
root->augment_cb(parent);
|
||||
|
||||
root->augment_cb(node);
|
||||
|
||||
if (old_parent_cb)
|
||||
root->augment_cb(rb_parent(old));
|
||||
}
|
||||
|
||||
goto color;
|
||||
}
|
||||
|
||||
|
|
@ -267,15 +303,19 @@ void rb_erase(struct rb_node *node, struct rb_root *root)
|
|||
|
||||
if (child)
|
||||
rb_set_parent(child, parent);
|
||||
if (parent)
|
||||
{
|
||||
|
||||
if (parent) {
|
||||
if (parent->rb_left == node)
|
||||
parent->rb_left = child;
|
||||
else
|
||||
parent->rb_right = child;
|
||||
}
|
||||
else
|
||||
|
||||
if (root->augment_cb)
|
||||
root->augment_cb(parent);
|
||||
|
||||
} else {
|
||||
root->rb_node = child;
|
||||
}
|
||||
|
||||
color:
|
||||
if (color == RB_BLACK)
|
||||
|
|
|
|||
Loading…
Reference in a new issue