constify-static-data-that-is-never-modified

   1 ext4: constify static data that is never modified
   2
   3 From: Eric Biggers <ebiggers@google.com>
   4
   5 Constify static data in ext4 that is never (intentionally) modified so
   6 that it is placed in .rodata and benefits from memory protection.
   7
   8 Signed-off-by: Eric Biggers <ebiggers@google.com>
   9 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  10 ---
  11  fs/ext4/ext4.h    | 4 ++--
  12  fs/ext4/mballoc.c | 2 +-
  13  fs/ext4/super.c   | 5 +++--
  14  fs/ext4/sysfs.c   | 8 ++++----
  15  fs/ext4/xattr.c   | 2 +-
  16  5 files changed, 11 insertions(+), 10 deletions(-)
  17
  18 diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
  19 index f493af666591..55f41bb14a5f 100644
  20 --- a/fs/ext4/ext4.h
  21 +++ b/fs/ext4/ext4.h
  22 @@ -2366,7 +2366,7 @@ static inline void ext4_update_dx_flag(struct inode *inode)
  23         if (!ext4_has_feature_dir_index(inode->i_sb))
  24                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
  25  }
  26 -static unsigned char ext4_filetype_table[] = {
  27 +static const unsigned char ext4_filetype_table[] = {
  28         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
  29  };
  30
  31 @@ -3050,7 +3050,7 @@ extern int ext4_handle_dirty_dirent_node(handle_t *handle,
  32                                          struct inode *inode,
  33                                          struct buffer_head *bh);
  34  #define S_SHIFT 12
  35 -static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
  36 +static const unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
  37         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
  38         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
  39         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
  40 diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
  41 index 354dc1a894c2..dbe51301c2bb 100644
  42 --- a/fs/ext4/mballoc.c
  43 +++ b/fs/ext4/mballoc.c
  44 @@ -357,7 +357,7 @@ static struct kmem_cache *ext4_free_data_cachep;
  45  #define NR_GRPINFO_CACHES 8
  46  static struct kmem_cache *ext4_groupinfo_caches[NR_GRPINFO_CACHES];
  47
  48 -static const char *ext4_groupinfo_slab_names[NR_GRPINFO_CACHES] = {
  49 +static const char * const ext4_groupinfo_slab_names[NR_GRPINFO_CACHES] = {
  50         "ext4_groupinfo_1k", "ext4_groupinfo_2k", "ext4_groupinfo_4k",
  51         "ext4_groupinfo_8k", "ext4_groupinfo_16k", "ext4_groupinfo_32k",
  52         "ext4_groupinfo_64k", "ext4_groupinfo_128k"
  53 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
  54 index 2e03a0a88d92..b3af13f808f1 100644
  55 --- a/fs/ext4/super.c
  56 +++ b/fs/ext4/super.c
  57 @@ -1210,7 +1210,7 @@ static const struct fscrypt_operations ext4_cryptops = {
  58  #endif
  59
  60  #ifdef CONFIG_QUOTA
  61 -static char *quotatypes[] = INITQFNAMES;
  62 +static const char * const quotatypes[] = INITQFNAMES;
  63  #define QTYPE2NAME(t) (quotatypes[t])
  64
  65  static int ext4_write_dquot(struct dquot *dquot);
  66 @@ -1424,7 +1424,8 @@ static ext4_fsblk_t get_sb_block(void **data)
  67  }
  68
  69  #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
  70 -static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
  71 +static const char deprecated_msg[] =
  72 +       "Mount option \"%s\" will be removed by %s\n"
  73         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
  74
  75  #ifdef CONFIG_QUOTA
  76 diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
  77 index 42145be5c6b4..d74dc5f81a04 100644
  78 --- a/fs/ext4/sysfs.c
  79 +++ b/fs/ext4/sysfs.c
  80 @@ -34,7 +34,7 @@ typedef enum {
  81         ptr_ext4_super_block_offset,
  82  } attr_ptr_t;
  83
  84 -static const char *proc_dirname = "fs/ext4";
  85 +static const char proc_dirname[] = "fs/ext4";
  86  static struct proc_dir_entry *ext4_proc_root;
  87
  88  struct ext4_attr {
  89 @@ -375,7 +375,7 @@ static const struct file_operations ext4_seq_##name##_fops = { \
  90  PROC_FILE_SHOW_DEFN(es_shrinker_info);
  91  PROC_FILE_SHOW_DEFN(options);
  92
  93 -static struct ext4_proc_files {
  94 +static const struct ext4_proc_files {
  95         const char *name;
  96         const struct file_operations *fops;
  97  } proc_files[] = {
  98 @@ -388,7 +388,7 @@ static struct ext4_proc_files {
  99  int ext4_register_sysfs(struct super_block *sb)
 100  {
 101         struct ext4_sb_info *sbi = EXT4_SB(sb);
 102 -       struct ext4_proc_files *p;
 103 +       const struct ext4_proc_files *p;
 104         int err;
 105
 106         sbi->s_kobj.kset = &ext4_kset;
 107 @@ -412,7 +412,7 @@ int ext4_register_sysfs(struct super_block *sb)
 108  void ext4_unregister_sysfs(struct super_block *sb)
 109  {
 110         struct ext4_sb_info *sbi = EXT4_SB(sb);
 111 -       struct ext4_proc_files *p;
 112 +       const struct ext4_proc_files *p;
 113
 114         if (sbi->s_proc) {
 115                 for (p = proc_files; p->name; p++)
 116 diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
 117 index 67636acf7624..9ab8f334233b 100644
 118 --- a/fs/ext4/xattr.c
 119 +++ b/fs/ext4/xattr.c
 120 @@ -81,7 +81,7 @@ static void ext4_xattr_rehash(struct ext4_xattr_header *,
 121  static int ext4_xattr_list(struct dentry *dentry, char *buffer,
 122                            size_t buffer_size);
 123
 124 -static const struct xattr_handler *ext4_xattr_handler_map[] = {
 125 +static const struct xattr_handler * const ext4_xattr_handler_map[] = {
 126         [EXT4_XATTR_INDEX_USER]              = &ext4_xattr_user_handler,
 127  #ifdef CONFIG_EXT4_FS_POSIX_ACL
 128         [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS]  = &posix_acl_access_xattr_handler,
 129 --
 130 2.12.0
 131
 132