linux/fs/hfsplus/catalog.c
Al Viro 323ee8fc54 hfsplus: switch to ->iterate_shared()
We need to protect the list of hfsplus_readdir_data against parallel
insertions (in readdir) and removals (in release).  Add a spinlock
for that.  Note that it has nothing to do with protection of
hfsplus_readdir_data->key - we have an exclusion between hfsplus_readdir()
and hfsplus_delete_cat() on directory lock and between several
hfsplus_readdir() for the same struct file on ->f_pos_lock.  The spinlock
is strictly for list changes.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-12 20:08:40 -04:00

525 lines
13 KiB
C

/*
* linux/fs/hfsplus/catalog.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Handling of catalog records
*/
#include "hfsplus_fs.h"
#include "hfsplus_raw.h"
int hfsplus_cat_case_cmp_key(const hfsplus_btree_key *k1,
const hfsplus_btree_key *k2)
{
__be32 k1p, k2p;
k1p = k1->cat.parent;
k2p = k2->cat.parent;
if (k1p != k2p)
return be32_to_cpu(k1p) < be32_to_cpu(k2p) ? -1 : 1;
return hfsplus_strcasecmp(&k1->cat.name, &k2->cat.name);
}
int hfsplus_cat_bin_cmp_key(const hfsplus_btree_key *k1,
const hfsplus_btree_key *k2)
{
__be32 k1p, k2p;
k1p = k1->cat.parent;
k2p = k2->cat.parent;
if (k1p != k2p)
return be32_to_cpu(k1p) < be32_to_cpu(k2p) ? -1 : 1;
return hfsplus_strcmp(&k1->cat.name, &k2->cat.name);
}
/* Generates key for catalog file/folders record. */
int hfsplus_cat_build_key(struct super_block *sb,
hfsplus_btree_key *key, u32 parent, struct qstr *str)
{
int len, err;
key->cat.parent = cpu_to_be32(parent);
err = hfsplus_asc2uni(sb, &key->cat.name, HFSPLUS_MAX_STRLEN,
str->name, str->len);
if (unlikely(err < 0))
return err;
len = be16_to_cpu(key->cat.name.length);
key->key_len = cpu_to_be16(6 + 2 * len);
return 0;
}
/* Generates key for catalog thread record. */
void hfsplus_cat_build_key_with_cnid(struct super_block *sb,
hfsplus_btree_key *key, u32 parent)
{
key->cat.parent = cpu_to_be32(parent);
key->cat.name.length = 0;
key->key_len = cpu_to_be16(6);
}
static void hfsplus_cat_build_key_uni(hfsplus_btree_key *key, u32 parent,
struct hfsplus_unistr *name)
{
int ustrlen;
ustrlen = be16_to_cpu(name->length);
key->cat.parent = cpu_to_be32(parent);
key->cat.name.length = cpu_to_be16(ustrlen);
ustrlen *= 2;
memcpy(key->cat.name.unicode, name->unicode, ustrlen);
key->key_len = cpu_to_be16(6 + ustrlen);
}
void hfsplus_cat_set_perms(struct inode *inode, struct hfsplus_perm *perms)
{
if (inode->i_flags & S_IMMUTABLE)
perms->rootflags |= HFSPLUS_FLG_IMMUTABLE;
else
perms->rootflags &= ~HFSPLUS_FLG_IMMUTABLE;
if (inode->i_flags & S_APPEND)
perms->rootflags |= HFSPLUS_FLG_APPEND;
else
perms->rootflags &= ~HFSPLUS_FLG_APPEND;
perms->userflags = HFSPLUS_I(inode)->userflags;
perms->mode = cpu_to_be16(inode->i_mode);
perms->owner = cpu_to_be32(i_uid_read(inode));
perms->group = cpu_to_be32(i_gid_read(inode));
if (S_ISREG(inode->i_mode))
perms->dev = cpu_to_be32(inode->i_nlink);
else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode))
perms->dev = cpu_to_be32(inode->i_rdev);
else
perms->dev = 0;
}
static int hfsplus_cat_build_record(hfsplus_cat_entry *entry,
u32 cnid, struct inode *inode)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
if (S_ISDIR(inode->i_mode)) {
struct hfsplus_cat_folder *folder;
folder = &entry->folder;
memset(folder, 0, sizeof(*folder));
folder->type = cpu_to_be16(HFSPLUS_FOLDER);
if (test_bit(HFSPLUS_SB_HFSX, &sbi->flags))
folder->flags |= cpu_to_be16(HFSPLUS_HAS_FOLDER_COUNT);
folder->id = cpu_to_be32(inode->i_ino);
HFSPLUS_I(inode)->create_date =
folder->create_date =
folder->content_mod_date =
folder->attribute_mod_date =
folder->access_date = hfsp_now2mt();
hfsplus_cat_set_perms(inode, &folder->permissions);
if (inode == sbi->hidden_dir)
/* invisible and namelocked */
folder->user_info.frFlags = cpu_to_be16(0x5000);
return sizeof(*folder);
} else {
struct hfsplus_cat_file *file;
file = &entry->file;
memset(file, 0, sizeof(*file));
file->type = cpu_to_be16(HFSPLUS_FILE);
file->flags = cpu_to_be16(HFSPLUS_FILE_THREAD_EXISTS);
file->id = cpu_to_be32(cnid);
HFSPLUS_I(inode)->create_date =
file->create_date =
file->content_mod_date =
file->attribute_mod_date =
file->access_date = hfsp_now2mt();
if (cnid == inode->i_ino) {
hfsplus_cat_set_perms(inode, &file->permissions);
if (S_ISLNK(inode->i_mode)) {
file->user_info.fdType =
cpu_to_be32(HFSP_SYMLINK_TYPE);
file->user_info.fdCreator =
cpu_to_be32(HFSP_SYMLINK_CREATOR);
} else {
file->user_info.fdType =
cpu_to_be32(sbi->type);
file->user_info.fdCreator =
cpu_to_be32(sbi->creator);
}
if (HFSPLUS_FLG_IMMUTABLE &
(file->permissions.rootflags |
file->permissions.userflags))
file->flags |=
cpu_to_be16(HFSPLUS_FILE_LOCKED);
} else {
file->user_info.fdType =
cpu_to_be32(HFSP_HARDLINK_TYPE);
file->user_info.fdCreator =
cpu_to_be32(HFSP_HFSPLUS_CREATOR);
file->user_info.fdFlags =
cpu_to_be16(0x100);
file->create_date =
HFSPLUS_I(sbi->hidden_dir)->create_date;
file->permissions.dev =
cpu_to_be32(HFSPLUS_I(inode)->linkid);
}
return sizeof(*file);
}
}
static int hfsplus_fill_cat_thread(struct super_block *sb,
hfsplus_cat_entry *entry, int type,
u32 parentid, struct qstr *str)
{
int err;
entry->type = cpu_to_be16(type);
entry->thread.reserved = 0;
entry->thread.parentID = cpu_to_be32(parentid);
err = hfsplus_asc2uni(sb, &entry->thread.nodeName, HFSPLUS_MAX_STRLEN,
str->name, str->len);
if (unlikely(err < 0))
return err;
return 10 + be16_to_cpu(entry->thread.nodeName.length) * 2;
}
/* Try to get a catalog entry for given catalog id */
int hfsplus_find_cat(struct super_block *sb, u32 cnid,
struct hfs_find_data *fd)
{
hfsplus_cat_entry tmp;
int err;
u16 type;
hfsplus_cat_build_key_with_cnid(sb, fd->search_key, cnid);
err = hfs_brec_read(fd, &tmp, sizeof(hfsplus_cat_entry));
if (err)
return err;
type = be16_to_cpu(tmp.type);
if (type != HFSPLUS_FOLDER_THREAD && type != HFSPLUS_FILE_THREAD) {
pr_err("found bad thread record in catalog\n");
return -EIO;
}
if (be16_to_cpu(tmp.thread.nodeName.length) > 255) {
pr_err("catalog name length corrupted\n");
return -EIO;
}
hfsplus_cat_build_key_uni(fd->search_key,
be32_to_cpu(tmp.thread.parentID),
&tmp.thread.nodeName);
return hfs_brec_find(fd, hfs_find_rec_by_key);
}
static void hfsplus_subfolders_inc(struct inode *dir)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
if (test_bit(HFSPLUS_SB_HFSX, &sbi->flags)) {
/*
* Increment subfolder count. Note, the value is only meaningful
* for folders with HFSPLUS_HAS_FOLDER_COUNT flag set.
*/
HFSPLUS_I(dir)->subfolders++;
}
}
static void hfsplus_subfolders_dec(struct inode *dir)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
if (test_bit(HFSPLUS_SB_HFSX, &sbi->flags)) {
/*
* Decrement subfolder count. Note, the value is only meaningful
* for folders with HFSPLUS_HAS_FOLDER_COUNT flag set.
*
* Check for zero. Some subfolders may have been created
* by an implementation ignorant of this counter.
*/
if (HFSPLUS_I(dir)->subfolders)
HFSPLUS_I(dir)->subfolders--;
}
}
int hfsplus_create_cat(u32 cnid, struct inode *dir,
struct qstr *str, struct inode *inode)
{
struct super_block *sb = dir->i_sb;
struct hfs_find_data fd;
hfsplus_cat_entry entry;
int entry_size;
int err;
hfs_dbg(CAT_MOD, "create_cat: %s,%u(%d)\n",
str->name, cnid, inode->i_nlink);
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
if (err)
return err;
hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid);
entry_size = hfsplus_fill_cat_thread(sb, &entry,
S_ISDIR(inode->i_mode) ?
HFSPLUS_FOLDER_THREAD : HFSPLUS_FILE_THREAD,
dir->i_ino, str);
if (unlikely(entry_size < 0)) {
err = entry_size;
goto err2;
}
err = hfs_brec_find(&fd, hfs_find_rec_by_key);
if (err != -ENOENT) {
if (!err)
err = -EEXIST;
goto err2;
}
err = hfs_brec_insert(&fd, &entry, entry_size);
if (err)
goto err2;
err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, str);
if (unlikely(err))
goto err1;
entry_size = hfsplus_cat_build_record(&entry, cnid, inode);
err = hfs_brec_find(&fd, hfs_find_rec_by_key);
if (err != -ENOENT) {
/* panic? */
if (!err)
err = -EEXIST;
goto err1;
}
err = hfs_brec_insert(&fd, &entry, entry_size);
if (err)
goto err1;
dir->i_size++;
if (S_ISDIR(inode->i_mode))
hfsplus_subfolders_inc(dir);
dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
hfsplus_mark_inode_dirty(dir, HFSPLUS_I_CAT_DIRTY);
hfs_find_exit(&fd);
return 0;
err1:
hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid);
if (!hfs_brec_find(&fd, hfs_find_rec_by_key))
hfs_brec_remove(&fd);
err2:
hfs_find_exit(&fd);
return err;
}
int hfsplus_delete_cat(u32 cnid, struct inode *dir, struct qstr *str)
{
struct super_block *sb = dir->i_sb;
struct hfs_find_data fd;
struct hfsplus_fork_raw fork;
struct list_head *pos;
int err, off;
u16 type;
hfs_dbg(CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
if (err)
return err;
if (!str) {
int len;
hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid);
err = hfs_brec_find(&fd, hfs_find_rec_by_key);
if (err)
goto out;
off = fd.entryoffset +
offsetof(struct hfsplus_cat_thread, nodeName);
fd.search_key->cat.parent = cpu_to_be32(dir->i_ino);
hfs_bnode_read(fd.bnode,
&fd.search_key->cat.name.length, off, 2);
len = be16_to_cpu(fd.search_key->cat.name.length) * 2;
hfs_bnode_read(fd.bnode,
&fd.search_key->cat.name.unicode,
off + 2, len);
fd.search_key->key_len = cpu_to_be16(6 + len);
} else {
err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, str);
if (unlikely(err))
goto out;
}
err = hfs_brec_find(&fd, hfs_find_rec_by_key);
if (err)
goto out;
type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
if (type == HFSPLUS_FILE) {
#if 0
off = fd.entryoffset + offsetof(hfsplus_cat_file, data_fork);
hfs_bnode_read(fd.bnode, &fork, off, sizeof(fork));
hfsplus_free_fork(sb, cnid, &fork, HFSPLUS_TYPE_DATA);
#endif
off = fd.entryoffset +
offsetof(struct hfsplus_cat_file, rsrc_fork);
hfs_bnode_read(fd.bnode, &fork, off, sizeof(fork));
hfsplus_free_fork(sb, cnid, &fork, HFSPLUS_TYPE_RSRC);
}
/* we only need to take spinlock for exclusion with ->release() */
spin_lock(&HFSPLUS_I(dir)->open_dir_lock);
list_for_each(pos, &HFSPLUS_I(dir)->open_dir_list) {
struct hfsplus_readdir_data *rd =
list_entry(pos, struct hfsplus_readdir_data, list);
if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
rd->file->f_pos--;
}
spin_unlock(&HFSPLUS_I(dir)->open_dir_lock);
err = hfs_brec_remove(&fd);
if (err)
goto out;
hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid);
err = hfs_brec_find(&fd, hfs_find_rec_by_key);
if (err)
goto out;
err = hfs_brec_remove(&fd);
if (err)
goto out;
dir->i_size--;
if (type == HFSPLUS_FOLDER)
hfsplus_subfolders_dec(dir);
dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
hfsplus_mark_inode_dirty(dir, HFSPLUS_I_CAT_DIRTY);
if (type == HFSPLUS_FILE || type == HFSPLUS_FOLDER) {
if (HFSPLUS_SB(sb)->attr_tree)
hfsplus_delete_all_attrs(dir, cnid);
}
out:
hfs_find_exit(&fd);
return err;
}
int hfsplus_rename_cat(u32 cnid,
struct inode *src_dir, struct qstr *src_name,
struct inode *dst_dir, struct qstr *dst_name)
{
struct super_block *sb = src_dir->i_sb;
struct hfs_find_data src_fd, dst_fd;
hfsplus_cat_entry entry;
int entry_size, type;
int err;
hfs_dbg(CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n",
cnid, src_dir->i_ino, src_name->name,
dst_dir->i_ino, dst_name->name);
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &src_fd);
if (err)
return err;
dst_fd = src_fd;
/* find the old dir entry and read the data */
err = hfsplus_cat_build_key(sb, src_fd.search_key,
src_dir->i_ino, src_name);
if (unlikely(err))
goto out;
err = hfs_brec_find(&src_fd, hfs_find_rec_by_key);
if (err)
goto out;
if (src_fd.entrylength > sizeof(entry) || src_fd.entrylength < 0) {
err = -EIO;
goto out;
}
hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
src_fd.entrylength);
type = be16_to_cpu(entry.type);
/* create new dir entry with the data from the old entry */
err = hfsplus_cat_build_key(sb, dst_fd.search_key,
dst_dir->i_ino, dst_name);
if (unlikely(err))
goto out;
err = hfs_brec_find(&dst_fd, hfs_find_rec_by_key);
if (err != -ENOENT) {
if (!err)
err = -EEXIST;
goto out;
}
err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
if (err)
goto out;
dst_dir->i_size++;
if (type == HFSPLUS_FOLDER)
hfsplus_subfolders_inc(dst_dir);
dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
/* finally remove the old entry */
err = hfsplus_cat_build_key(sb, src_fd.search_key,
src_dir->i_ino, src_name);
if (unlikely(err))
goto out;
err = hfs_brec_find(&src_fd, hfs_find_rec_by_key);
if (err)
goto out;
err = hfs_brec_remove(&src_fd);
if (err)
goto out;
src_dir->i_size--;
if (type == HFSPLUS_FOLDER)
hfsplus_subfolders_dec(src_dir);
src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
/* remove old thread entry */
hfsplus_cat_build_key_with_cnid(sb, src_fd.search_key, cnid);
err = hfs_brec_find(&src_fd, hfs_find_rec_by_key);
if (err)
goto out;
type = hfs_bnode_read_u16(src_fd.bnode, src_fd.entryoffset);
err = hfs_brec_remove(&src_fd);
if (err)
goto out;
/* create new thread entry */
hfsplus_cat_build_key_with_cnid(sb, dst_fd.search_key, cnid);
entry_size = hfsplus_fill_cat_thread(sb, &entry, type,
dst_dir->i_ino, dst_name);
if (unlikely(entry_size < 0)) {
err = entry_size;
goto out;
}
err = hfs_brec_find(&dst_fd, hfs_find_rec_by_key);
if (err != -ENOENT) {
if (!err)
err = -EEXIST;
goto out;
}
err = hfs_brec_insert(&dst_fd, &entry, entry_size);
hfsplus_mark_inode_dirty(dst_dir, HFSPLUS_I_CAT_DIRTY);
hfsplus_mark_inode_dirty(src_dir, HFSPLUS_I_CAT_DIRTY);
out:
hfs_bnode_put(dst_fd.bnode);
hfs_find_exit(&src_fd);
return err;
}