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x86: pat.c choose more crisp variable names
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 - parse/ml => entry (within list_for_each and friends)
 - new_entry => new
 - ret_type => new_type (to avoid confusion with req_type)

(... to make it more readable...)

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Suresh B Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Andreas Herrmann authored and Ingo Molnar committed Jun 24, 2008
1 parent bcc643d commit ac97991
Showing 1 changed file with 62 additions and 65 deletions.
127 changes: 62 additions & 65 deletions arch/x86/mm/pat.c
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Original file line number Diff line number Diff line change
Expand Up @@ -188,37 +188,34 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
* 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;
int err = 0;

/* Only track when pat_enabled */
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 & _PAGE_CACHE_MASK;
}
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 (is_ISA_range(start, end - 1)) {
if (ret_type)
*ret_type = _PAGE_CACHE_WB;

if (new_type)
*new_type = _PAGE_CACHE_WB;
return 0;
}

Expand All @@ -243,65 +240,65 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
actual_type = pat_x_mtrr_type(start, end, req_type);
}

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) {
list_for_each_entry(entry, &memtype_list, nd) {
struct memtype *saved_ptr;

if (parse->start >= end) {
if (entry->start >= end) {
dprintk("New Entry\n");
list_add(&new_entry->nd, parse->nd.prev);
new_entry = NULL;
list_add(&new->nd, entry->nd.prev);
new = NULL;
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 (start <= entry->start && end >= entry->start) {
if (actual_type != entry->type && new_type) {
actual_type = entry->type;
*new_type = actual_type;
new->type = actual_type;
}

if (actual_type != parse->type) {
if (actual_type != entry->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));
cattr_name(entry->type));
err = -EBUSY;
break;
}

saved_ptr = parse;
saved_ptr = entry;
/*
* 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) {
list_for_each_entry_continue(entry, &memtype_list, nd) {
if (end <= entry->start) {
break;
}

if (actual_type != parse->type) {
if (actual_type != entry->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));
cattr_name(entry->type));
err = -EBUSY;
break;
}
Expand All @@ -314,46 +311,46 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
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;
list_add(&new->nd, saved_ptr->nd.prev);
new = 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 (start < entry->end) {
if (actual_type != entry->type && new_type) {
actual_type = entry->type;
*new_type = actual_type;
new->type = actual_type;
}

if (actual_type != parse->type) {
if (actual_type != entry->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));
cattr_name(entry->type));
err = -EBUSY;
break;
}

saved_ptr = parse;
saved_ptr = entry;
/*
* 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) {
list_for_each_entry_continue(entry, &memtype_list, nd) {
if (end <= entry->start) {
break;
}

if (actual_type != parse->type) {
if (actual_type != entry->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));
cattr_name(entry->type));
err = -EBUSY;
break;
}
Expand All @@ -366,33 +363,33 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
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;
list_add(&new->nd, &saved_ptr->nd);
new = 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),
start, end, cattr_name(new->type),
cattr_name(req_type));
kfree(new_entry);
kfree(new);
spin_unlock(&memtype_lock);
return err;
}

if (new_entry) {
if (new) {
/* No conflict. Not yet added to the list. Add to the tail */
list_add_tail(&new_entry->nd, &memtype_list);
list_add_tail(&new->nd, &memtype_list);
dprintk("New Entry\n");
}

if (ret_type) {
if (new_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));
cattr_name(req_type), cattr_name(*new_type));
} else {
dprintk(
"reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s\n",
Expand All @@ -406,7 +403,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,

int free_memtype(u64 start, u64 end)
{
struct memtype *ml;
struct memtype *entry;
int err = -EINVAL;

/* Only track when pat_enabled */
Expand All @@ -419,10 +416,10 @@ int free_memtype(u64 start, u64 end)
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) {
list_del(&entry->nd);
kfree(entry);
err = 0;
break;
}
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