#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/bootmem.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
#include <asm/msr.h>
#include <asm/tlbflush.h>
#include <asm/io.h>
#ifdef CONFIG_X86_PAT
-int __read_mostly pat_wc_enabled = 1;
+int __read_mostly pat_enabled = 1;
void __cpuinit pat_disable(char *reason)
{
- pat_wc_enabled = 0;
+ pat_enabled = 0;
printk(KERN_INFO "%s\n", reason);
}
-static int nopat(char *str)
+static int __init nopat(char *str)
{
pat_disable("PAT support disabled.");
return 0;
PAT_UC_MINUS = 7, /* UC, but can be overriden by MTRR */
};
-#define PAT(x,y) ((u64)PAT_ ## y << ((x)*8))
+#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
void pat_init(void)
{
u64 pat;
- if (!pat_wc_enabled)
+ if (!pat_enabled)
return;
/* Paranoia check. */
- if (!cpu_has_pat) {
- printk(KERN_ERR "PAT enabled, but CPU feature cleared\n");
+ if (!cpu_has_pat && boot_pat_state) {
/*
- * Panic if this happens on the secondary CPU, and we
+ * If this happens we are on a secondary CPU, but
* switched to PAT on the boot CPU. We have no way to
* undo PAT.
- */
- BUG_ON(boot_pat_state);
+ */
+ printk(KERN_ERR "PAT enabled, "
+ "but not supported by secondary CPU\n");
+ BUG();
}
/* Set PWT to Write-Combining. All other bits stay the same */
* 011 UC _PAGE_CACHE_UC
* PAT bit unused
*/
- pat = PAT(0,WB) | PAT(1,WC) | PAT(2,UC_MINUS) | PAT(3,UC) |
- PAT(4,WB) | PAT(5,WC) | PAT(6,UC_MINUS) | PAT(7,UC);
+ pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
+ PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
/* Boot CPU check */
if (!boot_pat_state)
static 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";
+ 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";
}
}
* The intersection is based on "Effective Memory Type" tables in IA-32
* SDM vol 3a
*/
-static int pat_x_mtrr_type(u64 start, u64 end, unsigned long prot,
- unsigned long *ret_prot)
+static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
{
- unsigned long pat_type;
- u8 mtrr_type;
-
- pat_type = prot & _PAGE_CACHE_MASK;
- prot &= (~_PAGE_CACHE_MASK);
-
- /*
- * We return the PAT request directly for types where PAT takes
- * precedence with respect to MTRR and for UC_MINUS.
- * Consistency checks with other PAT requests is done later
- * while going through memtype list.
- */
- if (pat_type == _PAGE_CACHE_WC) {
- *ret_prot = prot | _PAGE_CACHE_WC;
- return 0;
- } else if (pat_type == _PAGE_CACHE_UC_MINUS) {
- *ret_prot = prot | _PAGE_CACHE_UC_MINUS;
- return 0;
- } else if (pat_type == _PAGE_CACHE_UC) {
- *ret_prot = prot | _PAGE_CACHE_UC;
- return 0;
- }
-
/*
* Look for MTRR hint to get the effective type in case where PAT
* request is for WB.
*/
- mtrr_type = mtrr_type_lookup(start, end);
+ if (req_type == _PAGE_CACHE_WB) {
+ u8 mtrr_type;
+
+ mtrr_type = mtrr_type_lookup(start, end);
+ if (mtrr_type == MTRR_TYPE_UNCACHABLE)
+ return _PAGE_CACHE_UC;
+ if (mtrr_type == MTRR_TYPE_WRCOMB)
+ return _PAGE_CACHE_WC;
+ }
- if (mtrr_type == MTRR_TYPE_UNCACHABLE) {
- *ret_prot = prot | _PAGE_CACHE_UC;
- } else if (mtrr_type == MTRR_TYPE_WRCOMB) {
- *ret_prot = prot | _PAGE_CACHE_WC;
- } else {
- *ret_prot = prot | _PAGE_CACHE_WB;
+ return req_type;
+}
+
+static int chk_conflict(struct memtype *new, struct memtype *entry,
+ unsigned long *type)
+{
+ if (new->type != entry->type) {
+ if (type) {
+ new->type = entry->type;
+ *type = entry->type;
+ } else
+ goto conflict;
}
+ /* check overlaps with more than one entry in the list */
+ list_for_each_entry_continue(entry, &memtype_list, nd) {
+ if (new->end <= entry->start)
+ break;
+ else if (new->type != entry->type)
+ goto conflict;
+ }
return 0;
+
+ conflict:
+ printk(KERN_INFO "%s:%d conflicting memory types "
+ "%Lx-%Lx %s<->%s\n", current->comm, current->pid, new->start,
+ new->end, cattr_name(new->type), cattr_name(entry->type));
+ return -EBUSY;
}
+static struct memtype *cached_entry;
+static u64 cached_start;
+
/*
* req_type typically has one of the:
* - _PAGE_CACHE_WB
* req_type will have a special case value '-1', when requester want to inherit
* the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
*
- * If ret_type is NULL, function will return an error if it cannot reserve the
- * region with req_type. If ret_type is non-null, function will return
- * available type in ret_type in case of no error. In case of any error
+ * If new_type is NULL, function will return an error if it cannot reserve the
+ * region with req_type. If new_type is non-NULL, function will return
+ * available type in new_type in case of no error. In case of any error
* it will return a negative return value.
*/
int reserve_memtype(u64 start, u64 end, unsigned long req_type,
- unsigned long *ret_type)
+ unsigned long *new_type)
{
- struct memtype *new_entry = NULL;
- struct memtype *parse;
+ struct memtype *new, *entry;
unsigned long actual_type;
+ struct list_head *where;
int err = 0;
- /* Only track when pat_wc_enabled */
- if (!pat_wc_enabled) {
+ BUG_ON(start >= end); /* end is exclusive */
+
+ if (!pat_enabled) {
/* This is identical to page table setting without PAT */
- if (ret_type) {
- if (req_type == -1) {
- *ret_type = _PAGE_CACHE_WB;
- } else {
- *ret_type = req_type;
- }
+ if (new_type) {
+ if (req_type == -1)
+ *new_type = _PAGE_CACHE_WB;
+ else
+ *new_type = req_type & _PAGE_CACHE_MASK;
}
return 0;
}
/* Low ISA region is always mapped WB in page table. No need to track */
- if (start >= ISA_START_ADDRESS && (end - 1) <= ISA_END_ADDRESS) {
- if (ret_type)
- *ret_type = _PAGE_CACHE_WB;
-
+ if (is_ISA_range(start, end - 1)) {
+ if (new_type)
+ *new_type = _PAGE_CACHE_WB;
return 0;
}
*/
u8 mtrr_type = mtrr_type_lookup(start, end);
- if (mtrr_type == MTRR_TYPE_WRBACK) {
- req_type = _PAGE_CACHE_WB;
+ if (mtrr_type == MTRR_TYPE_WRBACK)
actual_type = _PAGE_CACHE_WB;
- } else {
- req_type = _PAGE_CACHE_UC_MINUS;
+ else
actual_type = _PAGE_CACHE_UC_MINUS;
- }
- } else {
- req_type &= _PAGE_CACHE_MASK;
- err = pat_x_mtrr_type(start, end, req_type, &actual_type);
- }
-
- if (err) {
- if (ret_type)
- *ret_type = actual_type;
-
- return -EINVAL;
- }
+ } else
+ actual_type = pat_x_mtrr_type(start, end,
+ req_type & _PAGE_CACHE_MASK);
- new_entry = kmalloc(sizeof(struct memtype), GFP_KERNEL);
- if (!new_entry)
+ new = kmalloc(sizeof(struct memtype), GFP_KERNEL);
+ if (!new)
return -ENOMEM;
- new_entry->start = start;
- new_entry->end = end;
- new_entry->type = actual_type;
+ new->start = start;
+ new->end = end;
+ new->type = actual_type;
- if (ret_type)
- *ret_type = actual_type;
+ if (new_type)
+ *new_type = actual_type;
spin_lock(&memtype_lock);
- /* Search for existing mapping that overlaps the current range */
- list_for_each_entry(parse, &memtype_list, nd) {
- struct memtype *saved_ptr;
+ if (cached_entry && start >= cached_start)
+ entry = cached_entry;
+ else
+ entry = list_entry(&memtype_list, struct memtype, nd);
- if (parse->start >= end) {
- dprintk("New Entry\n");
- list_add(&new_entry->nd, parse->nd.prev);
- new_entry = NULL;
+ /* Search for existing mapping that overlaps the current range */
+ where = NULL;
+ list_for_each_entry_continue(entry, &memtype_list, nd) {
+ if (end <= entry->start) {
+ where = entry->nd.prev;
+ cached_entry = list_entry(where, struct memtype, nd);
break;
- }
-
- if (start <= parse->start && end >= parse->start) {
- if (actual_type != parse->type && ret_type) {
- actual_type = parse->type;
- *ret_type = actual_type;
- new_entry->type = actual_type;
- }
-
- if (actual_type != parse->type) {
- printk(
- KERN_INFO "%s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
- current->comm, current->pid,
- start, end,
- cattr_name(actual_type),
- cattr_name(parse->type));
- err = -EBUSY;
- break;
- }
-
- saved_ptr = parse;
- /*
- * Check to see whether the request overlaps more
- * than one entry in the list
- */
- list_for_each_entry_continue(parse, &memtype_list, nd) {
- if (end <= parse->start) {
- break;
- }
-
- if (actual_type != parse->type) {
- printk(
- KERN_INFO "%s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
- current->comm, current->pid,
- start, end,
- cattr_name(actual_type),
- cattr_name(parse->type));
- err = -EBUSY;
- break;
- }
- }
-
- if (err) {
- 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;
+ cached_entry = list_entry(where,
+ struct memtype, nd);
}
-
- dprintk("Overlap at 0x%Lx-0x%Lx\n",
- saved_ptr->start, saved_ptr->end);
- /* No conflict. Go ahead and add this new entry */
- list_add(&new_entry->nd, saved_ptr->nd.prev);
- new_entry = NULL;
break;
- }
-
- if (start < parse->end) {
- if (actual_type != parse->type && ret_type) {
- actual_type = parse->type;
- *ret_type = actual_type;
- new_entry->type = actual_type;
- }
-
- if (actual_type != parse->type) {
- printk(
- KERN_INFO "%s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
- current->comm, current->pid,
- start, end,
- cattr_name(actual_type),
- cattr_name(parse->type));
- err = -EBUSY;
- break;
- }
-
- saved_ptr = parse;
- /*
- * Check to see whether the request overlaps more
- * than one entry in the list
- */
- list_for_each_entry_continue(parse, &memtype_list, nd) {
- if (end <= parse->start) {
- 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);
+ cached_entry = list_entry(entry->nd.prev,
+ struct memtype, nd);
+
+ /*
+ * 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;
+ }
}
-
- if (actual_type != parse->type) {
- printk(
- KERN_INFO "%s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
- current->comm, current->pid,
- start, end,
- cattr_name(actual_type),
- cattr_name(parse->type));
- err = -EBUSY;
- break;
- }
- }
-
- if (err) {
- break;
}
-
- dprintk("Overlap at 0x%Lx-0x%Lx\n",
- saved_ptr->start, saved_ptr->end);
- /* No conflict. Go ahead and add this new entry */
- list_add(&new_entry->nd, &saved_ptr->nd);
- new_entry = NULL;
break;
}
}
if (err) {
- printk(KERN_INFO
- "reserve_memtype failed 0x%Lx-0x%Lx, track %s, req %s\n",
- start, end, cattr_name(new_entry->type),
- cattr_name(req_type));
- kfree(new_entry);
+ printk(KERN_INFO "reserve_memtype failed 0x%Lx-0x%Lx, "
+ "track %s, req %s\n",
+ start, end, cattr_name(new->type), cattr_name(req_type));
+ kfree(new);
spin_unlock(&memtype_lock);
return err;
}
- if (new_entry) {
- /* No conflict. Not yet added to the list. Add to the tail */
- list_add_tail(&new_entry->nd, &memtype_list);
- dprintk("New Entry\n");
- }
+ cached_start = start;
- if (ret_type) {
- dprintk(
- "reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
- start, end, cattr_name(actual_type),
- cattr_name(req_type), cattr_name(*ret_type));
- } else {
- dprintk(
- "reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s\n",
- start, end, cattr_name(actual_type),
- cattr_name(req_type));
- }
+ if (where)
+ list_add(&new->nd, where);
+ else
+ list_add_tail(&new->nd, &memtype_list);
spin_unlock(&memtype_lock);
+
+ dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
+ start, end, cattr_name(new->type), cattr_name(req_type),
+ new_type ? cattr_name(*new_type) : "-");
+
return err;
}
int free_memtype(u64 start, u64 end)
{
- struct memtype *ml;
+ struct memtype *entry;
int err = -EINVAL;
- /* Only track when pat_wc_enabled */
- if (!pat_wc_enabled) {
+ if (!pat_enabled)
return 0;
- }
/* Low ISA region is always mapped WB. No need to track */
- if (start >= ISA_START_ADDRESS && end <= ISA_END_ADDRESS) {
+ if (is_ISA_range(start, end - 1))
return 0;
- }
spin_lock(&memtype_lock);
- list_for_each_entry(ml, &memtype_list, nd) {
- if (ml->start == start && ml->end == end) {
- list_del(&ml->nd);
- kfree(ml);
+ list_for_each_entry(entry, &memtype_list, nd) {
+ if (entry->start == start && entry->end == end) {
+ if (cached_entry == entry || cached_start == start)
+ cached_entry = NULL;
+
+ list_del(&entry->nd);
+ kfree(entry);
err = 0;
break;
}
}
-/*
- * /dev/mem mmap interface. The memtype used for mapping varies:
- * - Use UC for mappings with O_SYNC flag
- * - Without O_SYNC flag, if there is any conflict in reserve_memtype,
- * inherit the memtype from existing mapping.
- * - Else use UC_MINUS memtype (for backward compatibility with existing
- * X drivers.
- */
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
return vma_prot;
}
-#ifdef CONFIG_NONPROMISC_DEVMEM
-/* This check is done in drivers/char/mem.c in case of NONPROMISC_DEVMEM*/
+#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;
}
return 1;
}
-#endif /* CONFIG_NONPROMISC_DEVMEM */
+#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 = _PAGE_CACHE_UC_MINUS;
+ unsigned long flags = -1;
int retval;
if (!range_is_allowed(pfn, size))
return 0;
if (file->f_flags & O_SYNC) {
- flags = _PAGE_CACHE_UC;
+ flags = _PAGE_CACHE_UC_MINUS;
}
#ifdef CONFIG_X86_32
* caching for the high addresses through the KEN pin, but
* we maintain the tradition of paranoia in this code.
*/
- if (!pat_wc_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)) {
+ 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 mapping. Fail if we cannot.
+ * 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 != _PAGE_CACHE_UC_MINUS) {
+ 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_pfn_mapped &&
- ioremap_change_attr((unsigned long)__va(offset), size, flags) < 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",
free_memtype(addr, addr + size);
}
+#if defined(CONFIG_DEBUG_FS)
+
+/* 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 */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff