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-rw-r--r--fs/Makefile2
-rw-r--r--fs/aio.c21
-rw-r--r--fs/btrfs/ctree.c14
-rw-r--r--fs/btrfs/locking.c24
-rw-r--r--fs/btrfs/locking.h2
-rw-r--r--fs/dcache.c1
-rw-r--r--fs/isofs/inode.c42
-rw-r--r--fs/overlayfs/Kconfig2
-rw-r--r--fs/overlayfs/Makefile4
-rw-r--r--fs/overlayfs/dir.c31
-rw-r--r--fs/overlayfs/inode.c27
-rw-r--r--fs/overlayfs/readdir.c39
-rw-r--r--fs/overlayfs/super.c61
13 files changed, 167 insertions, 103 deletions
diff --git a/fs/Makefile b/fs/Makefile
index 34a1b9de..da0bbb4 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -104,7 +104,7 @@ obj-$(CONFIG_QNX6FS_FS) += qnx6/
obj-$(CONFIG_AUTOFS4_FS) += autofs4/
obj-$(CONFIG_ADFS_FS) += adfs/
obj-$(CONFIG_FUSE_FS) += fuse/
-obj-$(CONFIG_OVERLAYFS_FS) += overlayfs/
+obj-$(CONFIG_OVERLAY_FS) += overlayfs/
obj-$(CONFIG_UDF_FS) += udf/
obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/
obj-$(CONFIG_OMFS_FS) += omfs/
diff --git a/fs/aio.c b/fs/aio.c
index 84a7510..14b9315 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -165,6 +165,15 @@ static struct vfsmount *aio_mnt;
static const struct file_operations aio_ring_fops;
static const struct address_space_operations aio_ctx_aops;
+/* Backing dev info for aio fs.
+ * -no dirty page accounting or writeback happens
+ */
+static struct backing_dev_info aio_fs_backing_dev_info = {
+ .name = "aiofs",
+ .state = 0,
+ .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK | BDI_CAP_MAP_COPY,
+};
+
static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)
{
struct qstr this = QSTR_INIT("[aio]", 5);
@@ -176,6 +185,7 @@ static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)
inode->i_mapping->a_ops = &aio_ctx_aops;
inode->i_mapping->private_data = ctx;
+ inode->i_mapping->backing_dev_info = &aio_fs_backing_dev_info;
inode->i_size = PAGE_SIZE * nr_pages;
path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb, &this);
@@ -220,6 +230,9 @@ static int __init aio_setup(void)
if (IS_ERR(aio_mnt))
panic("Failed to create aio fs mount.");
+ if (bdi_init(&aio_fs_backing_dev_info))
+ panic("Failed to init aio fs backing dev info.");
+
kiocb_cachep = KMEM_CACHE(kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
@@ -281,11 +294,6 @@ static const struct file_operations aio_ring_fops = {
.mmap = aio_ring_mmap,
};
-static int aio_set_page_dirty(struct page *page)
-{
- return 0;
-}
-
#if IS_ENABLED(CONFIG_MIGRATION)
static int aio_migratepage(struct address_space *mapping, struct page *new,
struct page *old, enum migrate_mode mode)
@@ -357,7 +365,7 @@ out:
#endif
static const struct address_space_operations aio_ctx_aops = {
- .set_page_dirty = aio_set_page_dirty,
+ .set_page_dirty = __set_page_dirty_no_writeback,
#if IS_ENABLED(CONFIG_MIGRATION)
.migratepage = aio_migratepage,
#endif
@@ -412,7 +420,6 @@ static int aio_setup_ring(struct kioctx *ctx)
pr_debug("pid(%d) page[%d]->count=%d\n",
current->pid, i, page_count(page));
SetPageUptodate(page);
- SetPageDirty(page);
unlock_page(page);
ctx->ring_pages[i] = page;
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 19bc616..150822e 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -80,13 +80,6 @@ noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
{
int i;
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- /* lockdep really cares that we take all of these spinlocks
- * in the right order. If any of the locks in the path are not
- * currently blocking, it is going to complain. So, make really
- * really sure by forcing the path to blocking before we clear
- * the path blocking.
- */
if (held) {
btrfs_set_lock_blocking_rw(held, held_rw);
if (held_rw == BTRFS_WRITE_LOCK)
@@ -95,7 +88,6 @@ noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
held_rw = BTRFS_READ_LOCK_BLOCKING;
}
btrfs_set_path_blocking(p);
-#endif
for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) {
if (p->nodes[i] && p->locks[i]) {
@@ -107,10 +99,8 @@ noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
}
}
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
if (held)
btrfs_clear_lock_blocking_rw(held, held_rw);
-#endif
}
/* this also releases the path */
@@ -2893,7 +2883,7 @@ cow_done:
}
p->locks[level] = BTRFS_WRITE_LOCK;
} else {
- err = btrfs_try_tree_read_lock(b);
+ err = btrfs_tree_read_lock_atomic(b);
if (!err) {
btrfs_set_path_blocking(p);
btrfs_tree_read_lock(b);
@@ -3025,7 +3015,7 @@ again:
}
level = btrfs_header_level(b);
- err = btrfs_try_tree_read_lock(b);
+ err = btrfs_tree_read_lock_atomic(b);
if (!err) {
btrfs_set_path_blocking(p);
btrfs_tree_read_lock(b);
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 5665d21..f8229ef 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -128,6 +128,26 @@ again:
}
/*
+ * take a spinning read lock.
+ * returns 1 if we get the read lock and 0 if we don't
+ * this won't wait for blocking writers
+ */
+int btrfs_tree_read_lock_atomic(struct extent_buffer *eb)
+{
+ if (atomic_read(&eb->blocking_writers))
+ return 0;
+
+ read_lock(&eb->lock);
+ if (atomic_read(&eb->blocking_writers)) {
+ read_unlock(&eb->lock);
+ return 0;
+ }
+ atomic_inc(&eb->read_locks);
+ atomic_inc(&eb->spinning_readers);
+ return 1;
+}
+
+/*
* returns 1 if we get the read lock and 0 if we don't
* this won't wait for blocking writers
*/
@@ -158,9 +178,7 @@ int btrfs_try_tree_write_lock(struct extent_buffer *eb)
atomic_read(&eb->blocking_readers))
return 0;
- if (!write_trylock(&eb->lock))
- return 0;
-
+ write_lock(&eb->lock);
if (atomic_read(&eb->blocking_writers) ||
atomic_read(&eb->blocking_readers)) {
write_unlock(&eb->lock);
diff --git a/fs/btrfs/locking.h b/fs/btrfs/locking.h
index b81e0e9..c44a9d5 100644
--- a/fs/btrfs/locking.h
+++ b/fs/btrfs/locking.h
@@ -35,6 +35,8 @@ void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw);
void btrfs_assert_tree_locked(struct extent_buffer *eb);
int btrfs_try_tree_read_lock(struct extent_buffer *eb);
int btrfs_try_tree_write_lock(struct extent_buffer *eb);
+int btrfs_tree_read_lock_atomic(struct extent_buffer *eb);
+
static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw)
{
diff --git a/fs/dcache.c b/fs/dcache.c
index 3ffef7f..5bc72b0 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -778,6 +778,7 @@ restart:
struct dentry *parent = lock_parent(dentry);
if (likely(!dentry->d_lockref.count)) {
__dentry_kill(dentry);
+ dput(parent);
goto restart;
}
if (parent)
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index fe839b9..d67a16f 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -174,27 +174,6 @@ struct iso9660_options{
* Compute the hash for the isofs name corresponding to the dentry.
*/
static int
-isofs_hash_common(struct qstr *qstr, int ms)
-{
- const char *name;
- int len;
-
- len = qstr->len;
- name = qstr->name;
- if (ms) {
- while (len && name[len-1] == '.')
- len--;
- }
-
- qstr->hash = full_name_hash(name, len);
-
- return 0;
-}
-
-/*
- * Compute the hash for the isofs name corresponding to the dentry.
- */
-static int
isofs_hashi_common(struct qstr *qstr, int ms)
{
const char *name;
@@ -263,6 +242,27 @@ isofs_dentry_cmpi(const struct dentry *parent, const struct dentry *dentry,
}
#ifdef CONFIG_JOLIET
+/*
+ * Compute the hash for the isofs name corresponding to the dentry.
+ */
+static int
+isofs_hash_common(struct qstr *qstr, int ms)
+{
+ const char *name;
+ int len;
+
+ len = qstr->len;
+ name = qstr->name;
+ if (ms) {
+ while (len && name[len-1] == '.')
+ len--;
+ }
+
+ qstr->hash = full_name_hash(name, len);
+
+ return 0;
+}
+
static int
isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
{
diff --git a/fs/overlayfs/Kconfig b/fs/overlayfs/Kconfig
index e601259..3435581 100644
--- a/fs/overlayfs/Kconfig
+++ b/fs/overlayfs/Kconfig
@@ -1,4 +1,4 @@
-config OVERLAYFS_FS
+config OVERLAY_FS
tristate "Overlay filesystem support"
help
An overlay filesystem combines two filesystems - an 'upper' filesystem
diff --git a/fs/overlayfs/Makefile b/fs/overlayfs/Makefile
index 8f91889..900daed 100644
--- a/fs/overlayfs/Makefile
+++ b/fs/overlayfs/Makefile
@@ -2,6 +2,6 @@
# Makefile for the overlay filesystem.
#
-obj-$(CONFIG_OVERLAYFS_FS) += overlayfs.o
+obj-$(CONFIG_OVERLAY_FS) += overlay.o
-overlayfs-objs := super.o inode.o dir.o readdir.o copy_up.o
+overlay-objs := super.o inode.o dir.o readdir.o copy_up.o
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 15cd91a..8ffc4b9 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -284,8 +284,7 @@ out:
return ERR_PTR(err);
}
-static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry,
- enum ovl_path_type type)
+static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry)
{
int err;
struct dentry *ret = NULL;
@@ -294,8 +293,17 @@ static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry,
err = ovl_check_empty_dir(dentry, &list);
if (err)
ret = ERR_PTR(err);
- else if (type == OVL_PATH_MERGE)
- ret = ovl_clear_empty(dentry, &list);
+ else {
+ /*
+ * If no upperdentry then skip clearing whiteouts.
+ *
+ * Can race with copy-up, since we don't hold the upperdir
+ * mutex. Doesn't matter, since copy-up can't create a
+ * non-empty directory from an empty one.
+ */
+ if (ovl_dentry_upper(dentry))
+ ret = ovl_clear_empty(dentry, &list);
+ }
ovl_cache_free(&list);
@@ -487,8 +495,7 @@ out:
return err;
}
-static int ovl_remove_and_whiteout(struct dentry *dentry,
- enum ovl_path_type type, bool is_dir)
+static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
{
struct dentry *workdir = ovl_workdir(dentry);
struct inode *wdir = workdir->d_inode;
@@ -500,7 +507,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry,
int err;
if (is_dir) {
- opaquedir = ovl_check_empty_and_clear(dentry, type);
+ opaquedir = ovl_check_empty_and_clear(dentry);
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir))
goto out;
@@ -515,9 +522,10 @@ static int ovl_remove_and_whiteout(struct dentry *dentry,
if (IS_ERR(whiteout))
goto out_unlock;
- if (type == OVL_PATH_LOWER) {
+ upper = ovl_dentry_upper(dentry);
+ if (!upper) {
upper = lookup_one_len(dentry->d_name.name, upperdir,
- dentry->d_name.len);
+ dentry->d_name.len);
err = PTR_ERR(upper);
if (IS_ERR(upper))
goto kill_whiteout;
@@ -529,7 +537,6 @@ static int ovl_remove_and_whiteout(struct dentry *dentry,
} else {
int flags = 0;
- upper = ovl_dentry_upper(dentry);
if (opaquedir)
upper = opaquedir;
err = -ESTALE;
@@ -648,7 +655,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir)
cap_raise(override_cred->cap_effective, CAP_CHOWN);
old_cred = override_creds(override_cred);
- err = ovl_remove_and_whiteout(dentry, type, is_dir);
+ err = ovl_remove_and_whiteout(dentry, is_dir);
revert_creds(old_cred);
put_cred(override_cred);
@@ -781,7 +788,7 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old,
}
if (overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) {
- opaquedir = ovl_check_empty_and_clear(new, new_type);
+ opaquedir = ovl_check_empty_and_clear(new);
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir)) {
opaquedir = NULL;
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index af2d18c..07d74b2 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -235,26 +235,36 @@ out:
return err;
}
+static bool ovl_need_xattr_filter(struct dentry *dentry,
+ enum ovl_path_type type)
+{
+ return type == OVL_PATH_UPPER && S_ISDIR(dentry->d_inode->i_mode);
+}
+
ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
void *value, size_t size)
{
- if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
- ovl_is_private_xattr(name))
+ struct path realpath;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
+
+ if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
return -ENODATA;
- return vfs_getxattr(ovl_dentry_real(dentry), name, value, size);
+ return vfs_getxattr(realpath.dentry, name, value, size);
}
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
{
+ struct path realpath;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
ssize_t res;
int off;
- res = vfs_listxattr(ovl_dentry_real(dentry), list, size);
+ res = vfs_listxattr(realpath.dentry, list, size);
if (res <= 0 || size == 0)
return res;
- if (ovl_path_type(dentry->d_parent) != OVL_PATH_MERGE)
+ if (!ovl_need_xattr_filter(dentry, type))
return res;
/* filter out private xattrs */
@@ -279,17 +289,16 @@ int ovl_removexattr(struct dentry *dentry, const char *name)
{
int err;
struct path realpath;
- enum ovl_path_type type;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
err = ovl_want_write(dentry);
if (err)
goto out;
- if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
- ovl_is_private_xattr(name))
+ err = -ENODATA;
+ if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
goto out_drop_write;
- type = ovl_path_real(dentry, &realpath);
if (type == OVL_PATH_LOWER) {
err = vfs_getxattr(realpath.dentry, name, NULL, 0);
if (err < 0)
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 2a7ef4f..ab1e3dc 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -274,11 +274,11 @@ static int ovl_dir_mark_whiteouts(struct dentry *dir,
return 0;
}
-static inline int ovl_dir_read_merged(struct path *upperpath,
- struct path *lowerpath,
- struct list_head *list)
+static int ovl_dir_read_merged(struct dentry *dentry, struct list_head *list)
{
int err;
+ struct path lowerpath;
+ struct path upperpath;
struct ovl_readdir_data rdd = {
.ctx.actor = ovl_fill_merge,
.list = list,
@@ -286,25 +286,28 @@ static inline int ovl_dir_read_merged(struct path *upperpath,
.is_merge = false,
};
- if (upperpath->dentry) {
- err = ovl_dir_read(upperpath, &rdd);
+ ovl_path_lower(dentry, &lowerpath);
+ ovl_path_upper(dentry, &upperpath);
+
+ if (upperpath.dentry) {
+ err = ovl_dir_read(&upperpath, &rdd);
if (err)
goto out;
- if (lowerpath->dentry) {
- err = ovl_dir_mark_whiteouts(upperpath->dentry, &rdd);
+ if (lowerpath.dentry) {
+ err = ovl_dir_mark_whiteouts(upperpath.dentry, &rdd);
if (err)
goto out;
}
}
- if (lowerpath->dentry) {
+ if (lowerpath.dentry) {
/*
* Insert lowerpath entries before upperpath ones, this allows
* offsets to be reasonably constant
*/
list_add(&rdd.middle, rdd.list);
rdd.is_merge = true;
- err = ovl_dir_read(lowerpath, &rdd);
+ err = ovl_dir_read(&lowerpath, &rdd);
list_del(&rdd.middle);
}
out:
@@ -329,8 +332,6 @@ static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
{
int res;
- struct path lowerpath;
- struct path upperpath;
struct ovl_dir_cache *cache;
cache = ovl_dir_cache(dentry);
@@ -347,10 +348,7 @@ static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
cache->refcount = 1;
INIT_LIST_HEAD(&cache->entries);
- ovl_path_lower(dentry, &lowerpath);
- ovl_path_upper(dentry, &upperpath);
-
- res = ovl_dir_read_merged(&upperpath, &lowerpath, &cache->entries);
+ res = ovl_dir_read_merged(dentry, &cache->entries);
if (res) {
ovl_cache_free(&cache->entries);
kfree(cache);
@@ -452,10 +450,10 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
/*
* Need to check if we started out being a lower dir, but got copied up
*/
- if (!od->is_upper && ovl_path_type(dentry) == OVL_PATH_MERGE) {
+ if (!od->is_upper && ovl_path_type(dentry) != OVL_PATH_LOWER) {
struct inode *inode = file_inode(file);
- realfile =lockless_dereference(od->upperfile);
+ realfile = lockless_dereference(od->upperfile);
if (!realfile) {
struct path upperpath;
@@ -538,14 +536,9 @@ const struct file_operations ovl_dir_operations = {
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)
{
int err;
- struct path lowerpath;
- struct path upperpath;
struct ovl_cache_entry *p;
- ovl_path_upper(dentry, &upperpath);
- ovl_path_lower(dentry, &lowerpath);
-
- err = ovl_dir_read_merged(&upperpath, &lowerpath, list);
+ err = ovl_dir_read_merged(dentry, list);
if (err)
return err;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 08b704c..f16d318 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -24,7 +24,7 @@ MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
MODULE_DESCRIPTION("Overlay filesystem");
MODULE_LICENSE("GPL");
-#define OVERLAYFS_SUPER_MAGIC 0x794c764f
+#define OVERLAYFS_SUPER_MAGIC 0x794c7630
struct ovl_config {
char *lowerdir;
@@ -84,12 +84,7 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry)
static struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe)
{
- struct dentry *upperdentry = ACCESS_ONCE(oe->__upperdentry);
- /*
- * Make sure to order reads to upperdentry wrt ovl_dentry_update()
- */
- smp_read_barrier_depends();
- return upperdentry;
+ return lockless_dereference(oe->__upperdentry);
}
void ovl_path_upper(struct dentry *dentry, struct path *path)
@@ -462,11 +457,34 @@ static const match_table_t ovl_tokens = {
{OPT_ERR, NULL}
};
+static char *ovl_next_opt(char **s)
+{
+ char *sbegin = *s;
+ char *p;
+
+ if (sbegin == NULL)
+ return NULL;
+
+ for (p = sbegin; *p; p++) {
+ if (*p == '\\') {
+ p++;
+ if (!*p)
+ break;
+ } else if (*p == ',') {
+ *p = '\0';
+ *s = p + 1;
+ return sbegin;
+ }
+ }
+ *s = NULL;
+ return sbegin;
+}
+
static int ovl_parse_opt(char *opt, struct ovl_config *config)
{
char *p;
- while ((p = strsep(&opt, ",")) != NULL) {
+ while ((p = ovl_next_opt(&opt)) != NULL) {
int token;
substring_t args[MAX_OPT_ARGS];
@@ -554,15 +572,34 @@ out_dput:
goto out_unlock;
}
+static void ovl_unescape(char *s)
+{
+ char *d = s;
+
+ for (;; s++, d++) {
+ if (*s == '\\')
+ s++;
+ *d = *s;
+ if (!*s)
+ break;
+ }
+}
+
static int ovl_mount_dir(const char *name, struct path *path)
{
int err;
+ char *tmp = kstrdup(name, GFP_KERNEL);
+
+ if (!tmp)
+ return -ENOMEM;
- err = kern_path(name, LOOKUP_FOLLOW, path);
+ ovl_unescape(tmp);
+ err = kern_path(tmp, LOOKUP_FOLLOW, path);
if (err) {
- pr_err("overlayfs: failed to resolve '%s': %i\n", name, err);
+ pr_err("overlayfs: failed to resolve '%s': %i\n", tmp, err);
err = -EINVAL;
}
+ kfree(tmp);
return err;
}
@@ -776,11 +813,11 @@ static struct dentry *ovl_mount(struct file_system_type *fs_type, int flags,
static struct file_system_type ovl_fs_type = {
.owner = THIS_MODULE,
- .name = "overlayfs",
+ .name = "overlay",
.mount = ovl_mount,
.kill_sb = kill_anon_super,
};
-MODULE_ALIAS_FS("overlayfs");
+MODULE_ALIAS_FS("overlay");
static int __init ovl_init(void)
{
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