| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20220508200755.24586-1-fmdefrancesco@gmail.com>
Date: Sun, 8 May 2022 22:07:55 +0200
From: "Fabio M. De Francesco" <fmdefrancesco@...il.com>
To: Evgeniy Dushistov <dushistov@...l.ru>,
Ira Weiny <ira.weiny@...el.com>, linux-kernel@...r.kernel.org
Cc: "Fabio M. De Francesco" <fmdefrancesco@...il.com>
Subject: [PATCH] fs/ufs: Replace kmap() with kmap_local_page()
The use of kmap() is being deprecated in favor of kmap_local_page(). With
kmap_local_page(), the mapping is per thread, CPU local and not globally
visible.
The usage of kmap_local_page() in fs/ufs is pre-thread, therefore replace
kmap() / kunmap() calls with kmap_local_page() / kunmap_local().
kunmap_local() requires the mapping address, so return that address from
ufs_get_page() to be used in ufs_put_page().
These changes are essentially ported from fs/ext2 and relie largely on
commit 782b76d7abdf ("fs/ext2: Replace kmap() with kmap_local_page()").
Suggested-by: Ira Weiny <ira.weiny@...el.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@...il.com>
---
fs/ufs/dir.c | 116 +++++++++++++++++++++++++++++++------------------
fs/ufs/namei.c | 38 ++++++++--------
fs/ufs/ufs.h | 12 +++--
3 files changed, 102 insertions(+), 64 deletions(-)
diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
index b721d0bda5e5..39e81547ebb9 100644
--- a/fs/ufs/dir.c
+++ b/fs/ufs/dir.c
@@ -61,9 +61,9 @@ static int ufs_commit_chunk(struct page *page, loff_t pos, unsigned len)
return err;
}
-static inline void ufs_put_page(struct page *page)
+inline void ufs_put_page(struct page *page, void *page_addr)
{
- kunmap(page);
+ kunmap_local(page_addr);
put_page(page);
}
@@ -72,11 +72,12 @@ ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr)
ino_t res = 0;
struct ufs_dir_entry *de;
struct page *page;
-
- de = ufs_find_entry(dir, qstr, &page);
+ void *page_addr;
+
+ de = ufs_find_entry(dir, qstr, &page, &page_addr);
if (de) {
res = fs32_to_cpu(dir->i_sb, de->d_ino);
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
}
return res;
}
@@ -84,11 +85,11 @@ ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr)
/* Releases the page */
void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
- struct page *page, struct inode *inode,
- bool update_times)
+ struct page *page, void *page_addr,
+ struct inode *inode, bool update_times)
{
loff_t pos = page_offset(page) +
- (char *) de - (char *) page_address(page);
+ (char *)de - (char *)page_addr;
unsigned len = fs16_to_cpu(dir->i_sb, de->d_reclen);
int err;
@@ -100,18 +101,17 @@ void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
ufs_set_de_type(dir->i_sb, de, inode->i_mode);
err = ufs_commit_chunk(page, pos, len);
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
if (update_times)
dir->i_mtime = dir->i_ctime = current_time(dir);
mark_inode_dirty(dir);
}
-static bool ufs_check_page(struct page *page)
+static bool ufs_check_page(struct page *page, char *kaddr)
{
struct inode *dir = page->mapping->host;
struct super_block *sb = dir->i_sb;
- char *kaddr = page_address(page);
unsigned offs, rec_len;
unsigned limit = PAGE_SIZE;
const unsigned chunk_mask = UFS_SB(sb)->s_uspi->s_dirblksize - 1;
@@ -186,21 +186,28 @@ static bool ufs_check_page(struct page *page)
return false;
}
-static struct page *ufs_get_page(struct inode *dir, unsigned long n)
+/*
+ * Calls to ufs_get_page()/ufs_put_page() must be nested according to the
+ * rules documented in kmap_local_page()/kunmap_local().
+ *
+ * NOTE: ufs_find_entry() and ufs_dotdot() act as calls to ufs_get_page()
+ * and must be treated accordingly for nesting purposes.
+ */
+static struct page *ufs_get_page(struct inode *dir, unsigned long n, void **page_addr)
{
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
- kmap(page);
+ *page_addr = kmap_local_page(page);
if (unlikely(!PageChecked(page))) {
- if (PageError(page) || !ufs_check_page(page))
+ if (PageError(page) || !ufs_check_page(page, *page_addr))
goto fail;
}
}
return page;
fail:
- ufs_put_page(page);
+ ufs_put_page(page, *page_addr);
return ERR_PTR(-EIO);
}
@@ -226,15 +233,29 @@ ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p)
fs16_to_cpu(sb, p->d_reclen));
}
-struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p)
+/*
+ * Return the '..' directory entry and the page in which the entry was found
+ * (as a parameter - p).
+ *
+ * On Success ufs_put_page() should be called on *p.
+ *
+ * NOTE: Calls to ufs_get_page()/ufs_put_page() must be nested according to
+ * the rules documented in kmap_local_page()/kunmap_local().
+ *
+ * ufs_find_entry() and ufs_dotdot() act as calls to ufs_get_page() and
+ * must be treated accordingly for nesting purposes.
+ */
+struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p, void **pa)
{
- struct page *page = ufs_get_page(dir, 0);
+ void *page_addr;
+ struct page *page = ufs_get_page(dir, 0, &page_addr);
struct ufs_dir_entry *de = NULL;
if (!IS_ERR(page)) {
de = ufs_next_entry(dir->i_sb,
- (struct ufs_dir_entry *)page_address(page));
+ (struct ufs_dir_entry *)page_addr);
*p = page;
+ *pa = page_addr;
}
return de;
}
@@ -246,9 +267,17 @@ struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p)
* returns the page in which the entry was found, and the entry itself
* (as a parameter - res_dir). Page is returned mapped and unlocked.
* Entry is guaranteed to be valid.
+ *
+ * On Success ufs_put_page() should be called on *res_page.
+ *
+ * NOTE: Calls to ufs_get_page()/ufs_put_page() must be nested according to
+ * the rules documented in kmap_local_page()/kunmap_local().
+ *
+ * ufs_find_entry() and ufs_dotdot() act as calls to ufs_get_page() and
+ * must be treated accordingly for nesting purposes.
*/
struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
- struct page **res_page)
+ struct page **res_page, void **res_page_addr)
{
struct super_block *sb = dir->i_sb;
const unsigned char *name = qstr->name;
@@ -259,6 +288,7 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
struct page *page = NULL;
struct ufs_inode_info *ui = UFS_I(dir);
struct ufs_dir_entry *de;
+ void *page_addr;
UFSD("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen);
@@ -267,6 +297,7 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
/* OFFSET_CACHE */
*res_page = NULL;
+ *res_page_addr = NULL;
start = ui->i_dir_start_lookup;
@@ -275,9 +306,10 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
n = start;
do {
char *kaddr;
- page = ufs_get_page(dir, n);
+
+ page = ufs_get_page(dir, n, &page_addr);
if (!IS_ERR(page)) {
- kaddr = page_address(page);
+ kaddr = page_addr;
de = (struct ufs_dir_entry *) kaddr;
kaddr += ufs_last_byte(dir, n) - reclen;
while ((char *) de <= kaddr) {
@@ -285,7 +317,7 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
goto found;
de = ufs_next_entry(sb, de);
}
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
}
if (++n >= npages)
n = 0;
@@ -295,6 +327,7 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
found:
*res_page = page;
+ *res_page_addr = page_addr;
ui->i_dir_start_lookup = n;
return de;
}
@@ -312,6 +345,7 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode)
const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize;
unsigned short rec_len, name_len;
struct page *page = NULL;
+ void *page_addr = NULL;
struct ufs_dir_entry *de;
unsigned long npages = dir_pages(dir);
unsigned long n;
@@ -329,12 +363,12 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode)
for (n = 0; n <= npages; n++) {
char *dir_end;
- page = ufs_get_page(dir, n);
+ page = ufs_get_page(dir, n, &page_addr);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
lock_page(page);
- kaddr = page_address(page);
+ kaddr = page_addr;
dir_end = kaddr + ufs_last_byte(dir, n);
de = (struct ufs_dir_entry *)kaddr;
kaddr += PAGE_SIZE - reclen;
@@ -365,14 +399,14 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode)
de = (struct ufs_dir_entry *) ((char *) de + rec_len);
}
unlock_page(page);
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
}
BUG();
return -EINVAL;
got_it:
pos = page_offset(page) +
- (char*)de - (char*)page_address(page);
+ (char *)de - (char *)page_addr;
err = ufs_prepare_chunk(page, pos, rec_len);
if (err)
goto out_unlock;
@@ -396,7 +430,7 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode)
mark_inode_dirty(dir);
/* OFFSET_CACHE */
out_put:
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
out:
return err;
out_unlock:
@@ -441,7 +475,7 @@ ufs_readdir(struct file *file, struct dir_context *ctx)
char *kaddr, *limit;
struct ufs_dir_entry *de;
- struct page *page = ufs_get_page(inode, n);
+ struct page *page = ufs_get_page(inode, n, (void **)&kaddr);
if (IS_ERR(page)) {
ufs_error(sb, __func__,
@@ -450,7 +484,6 @@ ufs_readdir(struct file *file, struct dir_context *ctx)
ctx->pos += PAGE_SIZE - offset;
return -EIO;
}
- kaddr = page_address(page);
if (unlikely(need_revalidate)) {
if (offset) {
offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask);
@@ -476,13 +509,13 @@ ufs_readdir(struct file *file, struct dir_context *ctx)
ufs_get_de_namlen(sb, de),
fs32_to_cpu(sb, de->d_ino),
d_type)) {
- ufs_put_page(page);
+ ufs_put_page(page, kaddr);
return 0;
}
}
ctx->pos += fs16_to_cpu(sb, de->d_reclen);
}
- ufs_put_page(page);
+ ufs_put_page(page, kaddr);
}
return 0;
}
@@ -493,10 +526,9 @@ ufs_readdir(struct file *file, struct dir_context *ctx)
* previous entry.
*/
int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir,
- struct page * page)
+ struct page *page, char *kaddr)
{
struct super_block *sb = inode->i_sb;
- char *kaddr = page_address(page);
unsigned from = ((char*)dir - kaddr) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1);
unsigned to = ((char*)dir - kaddr) + fs16_to_cpu(sb, dir->d_reclen);
loff_t pos;
@@ -522,7 +554,7 @@ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir,
de = ufs_next_entry(sb, de);
}
if (pde)
- from = (char*)pde - (char*)page_address(page);
+ from = (char *)pde - kaddr;
pos = page_offset(page) + from;
lock_page(page);
@@ -535,7 +567,7 @@ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir,
inode->i_ctime = inode->i_mtime = current_time(inode);
mark_inode_dirty(inode);
out:
- ufs_put_page(page);
+ ufs_put_page(page, kaddr);
UFSD("EXIT\n");
return err;
}
@@ -559,8 +591,7 @@ int ufs_make_empty(struct inode * inode, struct inode *dir)
goto fail;
}
- kmap(page);
- base = (char*)page_address(page);
+ base = kmap_local_page(page);
memset(base, 0, PAGE_SIZE);
de = (struct ufs_dir_entry *) base;
@@ -577,7 +608,7 @@ int ufs_make_empty(struct inode * inode, struct inode *dir)
de->d_reclen = cpu_to_fs16(sb, chunk_size - UFS_DIR_REC_LEN(1));
ufs_set_de_namlen(sb, de, 2);
strcpy (de->d_name, "..");
- kunmap(page);
+ kunmap_local(base);
err = ufs_commit_chunk(page, 0, chunk_size);
fail:
@@ -592,17 +623,18 @@ int ufs_empty_dir(struct inode * inode)
{
struct super_block *sb = inode->i_sb;
struct page *page = NULL;
+ void *page_addr;
unsigned long i, npages = dir_pages(inode);
for (i = 0; i < npages; i++) {
char *kaddr;
struct ufs_dir_entry *de;
- page = ufs_get_page(inode, i);
+ page = ufs_get_page(inode, i, &page_addr);
if (IS_ERR(page))
continue;
- kaddr = page_address(page);
+ kaddr = page_addr;
de = (struct ufs_dir_entry *)kaddr;
kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1);
@@ -629,12 +661,12 @@ int ufs_empty_dir(struct inode * inode)
}
de = ufs_next_entry(sb, de);
}
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
}
return 1;
not_empty:
- ufs_put_page(page);
+ ufs_put_page(page, page_addr);
return 0;
}
diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c
index 29d5a0e0c8f0..bc7060d10dd2 100644
--- a/fs/ufs/namei.c
+++ b/fs/ufs/namei.c
@@ -210,13 +210,14 @@ static int ufs_unlink(struct inode *dir, struct dentry *dentry)
struct inode * inode = d_inode(dentry);
struct ufs_dir_entry *de;
struct page *page;
+ void *page_addr;
int err = -ENOENT;
- de = ufs_find_entry(dir, &dentry->d_name, &page);
+ de = ufs_find_entry(dir, &dentry->d_name, &page, &page_addr);
if (!de)
goto out;
- err = ufs_delete_entry(dir, de, page);
+ err = ufs_delete_entry(dir, de, page, page_addr);
if (err)
goto out;
@@ -250,27 +251,31 @@ static int ufs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
struct inode *old_inode = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct page *dir_page = NULL;
+ void *dir_page_addr;
struct ufs_dir_entry * dir_de = NULL;
struct page *old_page;
+ void *old_page_addr;
struct ufs_dir_entry *old_de;
int err = -ENOENT;
if (flags & ~RENAME_NOREPLACE)
return -EINVAL;
- old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page);
+ old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page,
+ &old_page_addr);
if (!old_de)
goto out;
if (S_ISDIR(old_inode->i_mode)) {
err = -EIO;
- dir_de = ufs_dotdot(old_inode, &dir_page);
+ dir_de = ufs_dotdot(old_inode, &dir_page, &dir_page_addr);
if (!dir_de)
goto out_old;
}
if (new_inode) {
struct page *new_page;
+ void *page_addr;
struct ufs_dir_entry *new_de;
err = -ENOTEMPTY;
@@ -278,10 +283,11 @@ static int ufs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
goto out_dir;
err = -ENOENT;
- new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_page);
+ new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_page,
+ &page_addr);
if (!new_de)
goto out_dir;
- ufs_set_link(new_dir, new_de, new_page, old_inode, 1);
+ ufs_set_link(new_dir, new_de, new_page, page_addr, old_inode, 1);
new_inode->i_ctime = current_time(new_inode);
if (dir_de)
drop_nlink(new_inode);
@@ -300,29 +306,25 @@ static int ufs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
*/
old_inode->i_ctime = current_time(old_inode);
- ufs_delete_entry(old_dir, old_de, old_page);
+ ufs_delete_entry(old_dir, old_de, old_page, old_page_addr);
mark_inode_dirty(old_inode);
if (dir_de) {
if (old_dir != new_dir)
- ufs_set_link(old_inode, dir_de, dir_page, new_dir, 0);
- else {
- kunmap(dir_page);
- put_page(dir_page);
- }
+ ufs_set_link(old_inode, dir_de, dir_page,
+ dir_page_addr, new_dir, 0);
+ else
+ ufs_put_page(dir_page, dir_page_addr);
inode_dec_link_count(old_dir);
}
return 0;
out_dir:
- if (dir_de) {
- kunmap(dir_page);
- put_page(dir_page);
- }
+ if (dir_de)
+ ufs_put_page(dir_page, dir_page_addr);
out_old:
- kunmap(old_page);
- put_page(old_page);
+ ufs_put_page(old_page, old_page_addr);
out:
return err;
}
diff --git a/fs/ufs/ufs.h b/fs/ufs/ufs.h
index 550f7c5a3636..be02e5d1886b 100644
--- a/fs/ufs/ufs.h
+++ b/fs/ufs/ufs.h
@@ -102,12 +102,16 @@ extern const struct inode_operations ufs_dir_inode_operations;
extern int ufs_add_link (struct dentry *, struct inode *);
extern ino_t ufs_inode_by_name(struct inode *, const struct qstr *);
extern int ufs_make_empty(struct inode *, struct inode *);
-extern struct ufs_dir_entry *ufs_find_entry(struct inode *, const struct qstr *, struct page **);
-extern int ufs_delete_entry(struct inode *, struct ufs_dir_entry *, struct page *);
+extern struct ufs_dir_entry *ufs_find_entry(struct inode *, const struct qstr *,
+ struct page **, void **);
+extern int ufs_delete_entry(struct inode *, struct ufs_dir_entry *, struct page *,
+ char *);
extern int ufs_empty_dir (struct inode *);
-extern struct ufs_dir_entry *ufs_dotdot(struct inode *, struct page **);
+extern struct ufs_dir_entry *ufs_dotdot(struct inode *, struct page **, void **);
extern void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
- struct page *page, struct inode *inode, bool update_times);
+ struct page *page, void *page_addr,
+ struct inode *inode, bool update_times);
+extern inline void ufs_put_page(struct page *page, void *page_addr);
/* file.c */
extern const struct inode_operations ufs_file_inode_operations;
--
2.34.1
Powered by blists - more mailing lists