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-rw-r--r--arch/x86/mm/pat_interval.c185
1 files changed, 0 insertions, 185 deletions
diff --git a/arch/x86/mm/pat_interval.c b/arch/x86/mm/pat_interval.c
deleted file mode 100644
index 6855362eaf21..000000000000
--- a/arch/x86/mm/pat_interval.c
+++ /dev/null
@@ -1,185 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Handle caching attributes in page tables (PAT)
- *
- * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
- * Suresh B Siddha <suresh.b.siddha@intel.com>
- *
- * Interval tree used to store the PAT memory type reservations.
- */
-
-#include <linux/seq_file.h>
-#include <linux/debugfs.h>
-#include <linux/kernel.h>
-#include <linux/interval_tree_generic.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 inline u64 memtype_interval_start(struct memtype *memtype)
-{
- return memtype->start;
-}
-
-static inline u64 memtype_interval_end(struct memtype *memtype)
-{
- return memtype->end - 1;
-}
-INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
- memtype_interval_start, memtype_interval_end,
- static, memtype_interval)
-
-static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
-
-enum {
- MEMTYPE_EXACT_MATCH = 0,
- MEMTYPE_END_MATCH = 1
-};
-
-static struct memtype *memtype_match(u64 start, u64 end, int match_type)
-{
- struct memtype *match;
-
- match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
- while (match != NULL && match->start < end) {
- if ((match_type == MEMTYPE_EXACT_MATCH) &&
- (match->start == start) && (match->end == end))
- return match;
-
- if ((match_type == MEMTYPE_END_MATCH) &&
- (match->start < start) && (match->end == end))
- return match;
-
- match = memtype_interval_iter_next(match, start, end-1);
- }
-
- return NULL; /* Returns NULL if there is no match */
-}
-
-static int memtype_check_conflict(u64 start, u64 end,
- enum page_cache_mode reqtype,
- enum page_cache_mode *newtype)
-{
- struct memtype *match;
- enum page_cache_mode found_type = reqtype;
-
- match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
- 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;
-
- match = memtype_interval_iter_next(match, start, end-1);
- while (match) {
- if (match->type != found_type)
- goto failure;
-
- match = memtype_interval_iter_next(match, start, end-1);
- }
-success:
- if (newtype)
- *newtype = found_type;
-
- return 0;
-
-failure:
- pr_info("x86/PAT: %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;
-}
-
-int memtype_check_insert(struct memtype *new,
- enum page_cache_mode *ret_type)
-{
- int err = 0;
-
- err = memtype_check_conflict(new->start, new->end, new->type, ret_type);
- if (err)
- return err;
-
- if (ret_type)
- new->type = *ret_type;
-
- memtype_interval_insert(new, &memtype_rbroot);
- return 0;
-}
-
-struct memtype *memtype_erase(u64 start, u64 end)
-{
- struct memtype *data;
-
- /*
- * Since the memtype_rbroot tree allows overlapping ranges,
- * memtype_erase() checks with EXACT_MATCH first, i.e. free
- * a whole node for the munmap case. If no such entry is found,
- * it then checks with END_MATCH, i.e. shrink the size of a node
- * from the end for the mremap case.
- */
- data = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
- if (!data) {
- data = memtype_match(start, end, MEMTYPE_END_MATCH);
- if (!data)
- return ERR_PTR(-EINVAL);
- }
-
- if (data->start == start) {
- /* munmap: erase this node */
- memtype_interval_remove(data, &memtype_rbroot);
- } else {
- /* mremap: update the end value of this node */
- memtype_interval_remove(data, &memtype_rbroot);
- data->end = start;
- memtype_interval_insert(data, &memtype_rbroot);
- return NULL;
- }
-
- return data;
-}
-
-struct memtype *memtype_lookup(u64 addr)
-{
- return memtype_interval_iter_first(&memtype_rbroot, addr,
- addr + PAGE_SIZE-1);
-}
-
-#if defined(CONFIG_DEBUG_FS)
-int memtype_copy_nth_element(struct memtype *out, loff_t pos)
-{
- struct memtype *match;
- int i = 1;
-
- match = memtype_interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
- while (match && pos != i) {
- match = memtype_interval_iter_next(match, 0, ULONG_MAX);
- i++;
- }
-
- if (match) { /* pos == i */
- *out = *match;
- return 0;
- } else {
- return 1;
- }
-}
-#endif