[PATCH v4 10/21] NFS: Simplify struct nfs_cache_array_entry

trondmy
2020-11-07T14:13:46Z

We don't need to store a hash, so replace struct qstr with a simple
const char pointer and length.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
fs/nfs/dir.c | 46 +++++++++++++++++++++++++---------------------
1 file changed, 25 insertions(+), 21 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index b9001123ec84..be0e2891fecc 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -133,7 +133,8 @@ nfs_closedir(struct inode *inode, struct file *filp)
struct nfs_cache_array_entry {
u64 cookie;
u64 ino;
- struct qstr string;
+ const char *name;
+ unsigned int name_len;
unsigned char d_type;
};

@@ -192,7 +193,7 @@ void nfs_readdir_clear_array(struct page *page)

array = kmap_atomic(page);
for (i = 0; i < array->size; i++)
- kfree(array->array[i].string.name);
+ kfree(array->array[i].name);
nfs_readdir_array_init(array);
kunmap_atomic(array);
}
@@ -213,20 +214,17 @@ static bool nfs_readdir_array_is_full(struct nfs_cache_array *array)
* when called by nfs_readdir_add_to_array, the strings will be freed in
* nfs_clear_readdir_array()
*/
-static
-int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
+static const char *nfs_readdir_copy_name(const char *name, unsigned int len)
{
- string->len = len;
- string->name = kmemdup_nul(name, len, GFP_KERNEL);
- if (string->name == NULL)
- return -ENOMEM;
+ const char *ret = kmemdup_nul(name, len, GFP_KERNEL);
+
/*
* Avoid a kmemleak false positive. The pointer to the name is stored
* in a page cache page which kmemleak does not scan.
*/
- kmemleak_not_leak(string->name);
- string->hash = full_name_hash(NULL, name, len);
- return 0;
+ if (ret != NULL)
+ kmemleak_not_leak(ret);
+ return ret;
}

/*
@@ -249,27 +247,34 @@ static int nfs_readdir_array_can_expand(struct nfs_cache_array *array)
static
int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
{
- struct nfs_cache_array *array = kmap(page);
+ struct nfs_cache_array *array;
struct nfs_cache_array_entry *cache_entry;
+ const char *name;
int ret;

+ name = nfs_readdir_copy_name(entry->name, entry->len);
+ if (!name)
+ return -ENOMEM;
+
+ array = kmap_atomic(page);
ret = nfs_readdir_array_can_expand(array);
- if (ret)
+ if (ret) {
+ kfree(name);
goto out;
+ }

cache_entry = &array->array[array->size];
cache_entry->cookie = entry->prev_cookie;
cache_entry->ino = entry->ino;
cache_entry->d_type = entry->d_type;
- ret = nfs_readdir_make_qstr(&cache_entry->string, entry->name, entry->len);
- if (ret)
- goto out;
+ cache_entry->name_len = entry->len;
+ cache_entry->name = name;
array->last_cookie = entry->cookie;
array->size++;
if (entry->eof != 0)
nfs_readdir_array_set_eof(array);
out:
- kunmap(page);
+ kunmap_atomic(array);
return ret;
}

@@ -413,9 +418,8 @@ int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_des
if (printk_ratelimit()) {
pr_notice("NFS: directory %pD2 contains a readdir loop."
"Please contact your server vendor. "
- "The file: %.*s has duplicate cookie %llu\n",
- desc->file, array->array[i].string.len,
- array->array[i].string.name, desc->dir_cookie);
+ "The file: %s has duplicate cookie %llu\n",
+ desc->file, array->array[i].name, desc->dir_cookie);
}
status = -ELOOP;
goto out;
@@ -888,7 +892,7 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc)
struct nfs_cache_array_entry *ent;

ent = &array->array[i];
- if (!dir_emit(desc->ctx, ent->string.name, ent->string.len,
+ if (!dir_emit(desc->ctx, ent->name, ent->name_len,
nfs_compat_user_ino64(ent->ino), ent->d_type)) {
desc->eof = true;
break;
--
2.28.0