mm, hugetlb: unify region structure handling
Currently, to track reserved and allocated regions, we use two different
ways, depending on the mapping. For MAP_SHARED, we use
address_mapping's private_list and, while for MAP_PRIVATE, we use a
resv_map.
Now, we are preparing to change a coarse grained lock which protect a
region structure to fine grained lock, and this difference hinder it.
So, before changing it, unify region structure handling, consistently
using a resv_map regardless of the kind of mapping.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index d19b30a..2040275 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -366,7 +366,13 @@
static void hugetlbfs_evict_inode(struct inode *inode)
{
+ struct resv_map *resv_map;
+
truncate_hugepages(inode, 0);
+ resv_map = (struct resv_map *)inode->i_mapping->private_data;
+ /* root inode doesn't have the resv_map, so we should check it */
+ if (resv_map)
+ resv_map_release(&resv_map->refs);
clear_inode(inode);
}
@@ -476,6 +482,11 @@
umode_t mode, dev_t dev)
{
struct inode *inode;
+ struct resv_map *resv_map;
+
+ resv_map = resv_map_alloc();
+ if (!resv_map)
+ return NULL;
inode = new_inode(sb);
if (inode) {
@@ -487,7 +498,7 @@
inode->i_mapping->a_ops = &hugetlbfs_aops;
inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- INIT_LIST_HEAD(&inode->i_mapping->private_list);
+ inode->i_mapping->private_data = resv_map;
info = HUGETLBFS_I(inode);
/*
* The policy is initialized here even if we are creating a
@@ -517,7 +528,9 @@
break;
}
lockdep_annotate_inode_mutex_key(inode);
- }
+ } else
+ kref_put(&resv_map->refs, resv_map_release);
+
return inode;
}
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8c43cc4..f62c2f6 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -6,6 +6,8 @@
#include <linux/fs.h>
#include <linux/hugetlb_inline.h>
#include <linux/cgroup.h>
+#include <linux/list.h>
+#include <linux/kref.h>
struct ctl_table;
struct user_struct;
@@ -23,6 +25,13 @@
long max_hpages, used_hpages;
};
+struct resv_map {
+ struct kref refs;
+ struct list_head regions;
+};
+extern struct resv_map *resv_map_alloc(void);
+void resv_map_release(struct kref *ref);
+
extern spinlock_t hugetlb_lock;
extern int hugetlb_max_hstate __read_mostly;
#define for_each_hstate(h) \
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 139b746..63699af 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -376,12 +376,7 @@
vma->vm_private_data = (void *)value;
}
-struct resv_map {
- struct kref refs;
- struct list_head regions;
-};
-
-static struct resv_map *resv_map_alloc(void)
+struct resv_map *resv_map_alloc(void)
{
struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
if (!resv_map)
@@ -393,7 +388,7 @@
return resv_map;
}
-static void resv_map_release(struct kref *ref)
+void resv_map_release(struct kref *ref)
{
struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
@@ -1155,8 +1150,9 @@
if (vma->vm_flags & VM_MAYSHARE) {
pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- return region_chg(&inode->i_mapping->private_list,
- idx, idx + 1);
+ struct resv_map *resv = inode->i_mapping->private_data;
+
+ return region_chg(&resv->regions, idx, idx + 1);
} else if (!is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
return 1;
@@ -1180,7 +1176,9 @@
if (vma->vm_flags & VM_MAYSHARE) {
pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- region_add(&inode->i_mapping->private_list, idx, idx + 1);
+ struct resv_map *resv = inode->i_mapping->private_data;
+
+ region_add(&resv->regions, idx, idx + 1);
} else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
pgoff_t idx = vma_hugecache_offset(h, vma, addr);
@@ -3161,6 +3159,7 @@
long ret, chg;
struct hstate *h = hstate_inode(inode);
struct hugepage_subpool *spool = subpool_inode(inode);
+ struct resv_map *resv_map;
/*
* Only apply hugepage reservation if asked. At fault time, an
@@ -3176,10 +3175,13 @@
* to reserve the full area even if read-only as mprotect() may be
* called to make the mapping read-write. Assume !vma is a shm mapping
*/
- if (!vma || vma->vm_flags & VM_MAYSHARE)
- chg = region_chg(&inode->i_mapping->private_list, from, to);
- else {
- struct resv_map *resv_map = resv_map_alloc();
+ if (!vma || vma->vm_flags & VM_MAYSHARE) {
+ resv_map = inode->i_mapping->private_data;
+
+ chg = region_chg(&resv_map->regions, from, to);
+
+ } else {
+ resv_map = resv_map_alloc();
if (!resv_map)
return -ENOMEM;
@@ -3222,7 +3224,7 @@
* else has to be done for private mappings here
*/
if (!vma || vma->vm_flags & VM_MAYSHARE)
- region_add(&inode->i_mapping->private_list, from, to);
+ region_add(&resv_map->regions, from, to);
return 0;
out_err:
if (vma)
@@ -3233,9 +3235,12 @@
void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
{
struct hstate *h = hstate_inode(inode);
- long chg = region_truncate(&inode->i_mapping->private_list, offset);
+ struct resv_map *resv_map = inode->i_mapping->private_data;
+ long chg = 0;
struct hugepage_subpool *spool = subpool_inode(inode);
+ if (resv_map)
+ chg = region_truncate(&resv_map->regions, offset);
spin_lock(&inode->i_lock);
inode->i_blocks -= (blocks_per_huge_page(h) * freed);
spin_unlock(&inode->i_lock);