linux/fs/hfs/inode.c
Arjan van de Ven 92e1d5be91 [PATCH] mark struct inode_operations const 2
Many struct inode_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00

624 lines
17 KiB
C

/*
* linux/fs/hfs/inode.c
*
* Copyright (C) 1995-1997 Paul H. Hargrove
* (C) 2003 Ardis Technologies <roman@ardistech.com>
* This file may be distributed under the terms of the GNU General Public License.
*
* This file contains inode-related functions which do not depend on
* which scheme is being used to represent forks.
*
* Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
*/
#include <linux/pagemap.h>
#include <linux/mpage.h>
#include "hfs_fs.h"
#include "btree.h"
static const struct file_operations hfs_file_operations;
static const struct inode_operations hfs_file_inode_operations;
/*================ Variable-like macros ================*/
#define HFS_VALID_MODE_BITS (S_IFREG | S_IFDIR | S_IRWXUGO)
static int hfs_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page, hfs_get_block, wbc);
}
static int hfs_readpage(struct file *file, struct page *page)
{
return block_read_full_page(page, hfs_get_block);
}
static int hfs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
{
return cont_prepare_write(page, from, to, hfs_get_block,
&HFS_I(page->mapping->host)->phys_size);
}
static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping, block, hfs_get_block);
}
static int hfs_releasepage(struct page *page, gfp_t mask)
{
struct inode *inode = page->mapping->host;
struct super_block *sb = inode->i_sb;
struct hfs_btree *tree;
struct hfs_bnode *node;
u32 nidx;
int i, res = 1;
switch (inode->i_ino) {
case HFS_EXT_CNID:
tree = HFS_SB(sb)->ext_tree;
break;
case HFS_CAT_CNID:
tree = HFS_SB(sb)->cat_tree;
break;
default:
BUG();
return 0;
}
if (tree->node_size >= PAGE_CACHE_SIZE) {
nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
spin_lock(&tree->hash_lock);
node = hfs_bnode_findhash(tree, nidx);
if (!node)
;
else if (atomic_read(&node->refcnt))
res = 0;
if (res && node) {
hfs_bnode_unhash(node);
hfs_bnode_free(node);
}
spin_unlock(&tree->hash_lock);
} else {
nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
spin_lock(&tree->hash_lock);
do {
node = hfs_bnode_findhash(tree, nidx++);
if (!node)
continue;
if (atomic_read(&node->refcnt)) {
res = 0;
break;
}
hfs_bnode_unhash(node);
hfs_bnode_free(node);
} while (--i && nidx < tree->node_count);
spin_unlock(&tree->hash_lock);
}
return res ? try_to_free_buffers(page) : 0;
}
static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
const struct iovec *iov, loff_t offset, unsigned long nr_segs)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_path.dentry->d_inode->i_mapping->host;
return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
offset, nr_segs, hfs_get_block, NULL);
}
static int hfs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
return mpage_writepages(mapping, wbc, hfs_get_block);
}
const struct address_space_operations hfs_btree_aops = {
.readpage = hfs_readpage,
.writepage = hfs_writepage,
.sync_page = block_sync_page,
.prepare_write = hfs_prepare_write,
.commit_write = generic_commit_write,
.bmap = hfs_bmap,
.releasepage = hfs_releasepage,
};
const struct address_space_operations hfs_aops = {
.readpage = hfs_readpage,
.writepage = hfs_writepage,
.sync_page = block_sync_page,
.prepare_write = hfs_prepare_write,
.commit_write = generic_commit_write,
.bmap = hfs_bmap,
.direct_IO = hfs_direct_IO,
.writepages = hfs_writepages,
};
/*
* hfs_new_inode
*/
struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, int mode)
{
struct super_block *sb = dir->i_sb;
struct inode *inode = new_inode(sb);
if (!inode)
return NULL;
init_MUTEX(&HFS_I(inode)->extents_lock);
INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
inode->i_ino = HFS_SB(sb)->next_id++;
inode->i_mode = mode;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_nlink = 1;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
HFS_I(inode)->flags = 0;
HFS_I(inode)->rsrc_inode = NULL;
HFS_I(inode)->fs_blocks = 0;
if (S_ISDIR(mode)) {
inode->i_size = 2;
HFS_SB(sb)->folder_count++;
if (dir->i_ino == HFS_ROOT_CNID)
HFS_SB(sb)->root_dirs++;
inode->i_op = &hfs_dir_inode_operations;
inode->i_fop = &hfs_dir_operations;
inode->i_mode |= S_IRWXUGO;
inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
} else if (S_ISREG(mode)) {
HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
HFS_SB(sb)->file_count++;
if (dir->i_ino == HFS_ROOT_CNID)
HFS_SB(sb)->root_files++;
inode->i_op = &hfs_file_inode_operations;
inode->i_fop = &hfs_file_operations;
inode->i_mapping->a_ops = &hfs_aops;
inode->i_mode |= S_IRUGO|S_IXUGO;
if (mode & S_IWUSR)
inode->i_mode |= S_IWUGO;
inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
HFS_I(inode)->phys_size = 0;
HFS_I(inode)->alloc_blocks = 0;
HFS_I(inode)->first_blocks = 0;
HFS_I(inode)->cached_start = 0;
HFS_I(inode)->cached_blocks = 0;
memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
}
insert_inode_hash(inode);
mark_inode_dirty(inode);
set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
sb->s_dirt = 1;
return inode;
}
void hfs_delete_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
if (S_ISDIR(inode->i_mode)) {
HFS_SB(sb)->folder_count--;
if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
HFS_SB(sb)->root_dirs--;
set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
sb->s_dirt = 1;
return;
}
HFS_SB(sb)->file_count--;
if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
HFS_SB(sb)->root_files--;
if (S_ISREG(inode->i_mode)) {
if (!inode->i_nlink) {
inode->i_size = 0;
hfs_file_truncate(inode);
}
}
set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
sb->s_dirt = 1;
}
void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
__be32 __log_size, __be32 phys_size, u32 clump_size)
{
struct super_block *sb = inode->i_sb;
u32 log_size = be32_to_cpu(__log_size);
u16 count;
int i;
memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
for (count = 0, i = 0; i < 3; i++)
count += be16_to_cpu(ext[i].count);
HFS_I(inode)->first_blocks = count;
inode->i_size = HFS_I(inode)->phys_size = log_size;
HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
HFS_SB(sb)->alloc_blksz;
HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
if (!HFS_I(inode)->clump_blocks)
HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
}
struct hfs_iget_data {
struct hfs_cat_key *key;
hfs_cat_rec *rec;
};
static int hfs_test_inode(struct inode *inode, void *data)
{
struct hfs_iget_data *idata = data;
hfs_cat_rec *rec;
rec = idata->rec;
switch (rec->type) {
case HFS_CDR_DIR:
return inode->i_ino == be32_to_cpu(rec->dir.DirID);
case HFS_CDR_FIL:
return inode->i_ino == be32_to_cpu(rec->file.FlNum);
default:
BUG();
return 1;
}
}
/*
* hfs_read_inode
*/
static int hfs_read_inode(struct inode *inode, void *data)
{
struct hfs_iget_data *idata = data;
struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
hfs_cat_rec *rec;
HFS_I(inode)->flags = 0;
HFS_I(inode)->rsrc_inode = NULL;
init_MUTEX(&HFS_I(inode)->extents_lock);
INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
/* Initialize the inode */
inode->i_uid = hsb->s_uid;
inode->i_gid = hsb->s_gid;
inode->i_nlink = 1;
if (idata->key)
HFS_I(inode)->cat_key = *idata->key;
else
HFS_I(inode)->flags |= HFS_FLG_RSRC;
HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
rec = idata->rec;
switch (rec->type) {
case HFS_CDR_FIL:
if (!HFS_IS_RSRC(inode)) {
hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
} else {
hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
}
inode->i_ino = be32_to_cpu(rec->file.FlNum);
inode->i_mode = S_IRUGO | S_IXUGO;
if (!(rec->file.Flags & HFS_FIL_LOCK))
inode->i_mode |= S_IWUGO;
inode->i_mode &= ~hsb->s_file_umask;
inode->i_mode |= S_IFREG;
inode->i_ctime = inode->i_atime = inode->i_mtime =
hfs_m_to_utime(rec->file.MdDat);
inode->i_op = &hfs_file_inode_operations;
inode->i_fop = &hfs_file_operations;
inode->i_mapping->a_ops = &hfs_aops;
break;
case HFS_CDR_DIR:
inode->i_ino = be32_to_cpu(rec->dir.DirID);
inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
HFS_I(inode)->fs_blocks = 0;
inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
inode->i_ctime = inode->i_atime = inode->i_mtime =
hfs_m_to_utime(rec->dir.MdDat);
inode->i_op = &hfs_dir_inode_operations;
inode->i_fop = &hfs_dir_operations;
break;
default:
make_bad_inode(inode);
}
return 0;
}
/*
* __hfs_iget()
*
* Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
* the catalog B-tree and the 'type' of the desired file return the
* inode for that file/directory or NULL. Note that 'type' indicates
* whether we want the actual file or directory, or the corresponding
* metadata (AppleDouble header file or CAP metadata file).
*/
struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
{
struct hfs_iget_data data = { key, rec };
struct inode *inode;
u32 cnid;
switch (rec->type) {
case HFS_CDR_DIR:
cnid = be32_to_cpu(rec->dir.DirID);
break;
case HFS_CDR_FIL:
cnid = be32_to_cpu(rec->file.FlNum);
break;
default:
return NULL;
}
inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
if (inode && (inode->i_state & I_NEW))
unlock_new_inode(inode);
return inode;
}
void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
__be32 *log_size, __be32 *phys_size)
{
memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
if (log_size)
*log_size = cpu_to_be32(inode->i_size);
if (phys_size)
*phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
HFS_SB(inode->i_sb)->alloc_blksz);
}
int hfs_write_inode(struct inode *inode, int unused)
{
struct inode *main_inode = inode;
struct hfs_find_data fd;
hfs_cat_rec rec;
dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
hfs_ext_write_extent(inode);
if (inode->i_ino < HFS_FIRSTUSER_CNID) {
switch (inode->i_ino) {
case HFS_ROOT_CNID:
break;
case HFS_EXT_CNID:
hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
return 0;
case HFS_CAT_CNID:
hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
return 0;
default:
BUG();
return -EIO;
}
}
if (HFS_IS_RSRC(inode))
main_inode = HFS_I(inode)->rsrc_inode;
if (!main_inode->i_nlink)
return 0;
if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
/* panic? */
return -EIO;
fd.search_key->cat = HFS_I(main_inode)->cat_key;
if (hfs_brec_find(&fd))
/* panic? */
goto out;
if (S_ISDIR(main_inode->i_mode)) {
if (fd.entrylength < sizeof(struct hfs_cat_dir))
/* panic? */;
hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_dir));
if (rec.type != HFS_CDR_DIR ||
be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
}
rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
rec.dir.Val = cpu_to_be16(inode->i_size - 2);
hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_dir));
} else if (HFS_IS_RSRC(inode)) {
hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_file));
hfs_inode_write_fork(inode, rec.file.RExtRec,
&rec.file.RLgLen, &rec.file.RPyLen);
hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_file));
} else {
if (fd.entrylength < sizeof(struct hfs_cat_file))
/* panic? */;
hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_file));
if (rec.type != HFS_CDR_FIL ||
be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
}
if (inode->i_mode & S_IWUSR)
rec.file.Flags &= ~HFS_FIL_LOCK;
else
rec.file.Flags |= HFS_FIL_LOCK;
hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
sizeof(struct hfs_cat_file));
}
out:
hfs_find_exit(&fd);
return 0;
}
static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct inode *inode = NULL;
hfs_cat_rec rec;
struct hfs_find_data fd;
int res;
if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
goto out;
inode = HFS_I(dir)->rsrc_inode;
if (inode)
goto out;
inode = new_inode(dir->i_sb);
if (!inode)
return ERR_PTR(-ENOMEM);
hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
fd.search_key->cat = HFS_I(dir)->cat_key;
res = hfs_brec_read(&fd, &rec, sizeof(rec));
if (!res) {
struct hfs_iget_data idata = { NULL, &rec };
hfs_read_inode(inode, &idata);
}
hfs_find_exit(&fd);
if (res) {
iput(inode);
return ERR_PTR(res);
}
HFS_I(inode)->rsrc_inode = dir;
HFS_I(dir)->rsrc_inode = inode;
igrab(dir);
hlist_add_head(&inode->i_hash, &HFS_SB(dir->i_sb)->rsrc_inodes);
mark_inode_dirty(inode);
out:
d_add(dentry, inode);
return NULL;
}
void hfs_clear_inode(struct inode *inode)
{
if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
iput(HFS_I(inode)->rsrc_inode);
}
}
static int hfs_permission(struct inode *inode, int mask,
struct nameidata *nd)
{
if (S_ISREG(inode->i_mode) && mask & MAY_EXEC)
return 0;
return generic_permission(inode, mask, NULL);
}
static int hfs_file_open(struct inode *inode, struct file *file)
{
if (HFS_IS_RSRC(inode))
inode = HFS_I(inode)->rsrc_inode;
if (atomic_read(&file->f_count) != 1)
return 0;
atomic_inc(&HFS_I(inode)->opencnt);
return 0;
}
static int hfs_file_release(struct inode *inode, struct file *file)
{
//struct super_block *sb = inode->i_sb;
if (HFS_IS_RSRC(inode))
inode = HFS_I(inode)->rsrc_inode;
if (atomic_read(&file->f_count) != 0)
return 0;
if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
mutex_lock(&inode->i_mutex);
hfs_file_truncate(inode);
//if (inode->i_flags & S_DEAD) {
// hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
// hfs_delete_inode(inode);
//}
mutex_unlock(&inode->i_mutex);
}
return 0;
}
/*
* hfs_notify_change()
*
* Based very closely on fs/msdos/inode.c by Werner Almesberger
*
* This is the notify_change() field in the super_operations structure
* for HFS file systems. The purpose is to take that changes made to
* an inode and apply then in a filesystem-dependent manner. In this
* case the process has a few of tasks to do:
* 1) prevent changes to the i_uid and i_gid fields.
* 2) map file permissions to the closest allowable permissions
* 3) Since multiple Linux files can share the same on-disk inode under
* HFS (for instance the data and resource forks of a file) a change
* to permissions must be applied to all other in-core inodes which
* correspond to the same HFS file.
*/
int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
{
struct inode *inode = dentry->d_inode;
struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
int error;
error = inode_change_ok(inode, attr); /* basic permission checks */
if (error)
return error;
/* no uig/gid changes and limit which mode bits can be set */
if (((attr->ia_valid & ATTR_UID) &&
(attr->ia_uid != hsb->s_uid)) ||
((attr->ia_valid & ATTR_GID) &&
(attr->ia_gid != hsb->s_gid)) ||
((attr->ia_valid & ATTR_MODE) &&
((S_ISDIR(inode->i_mode) &&
(attr->ia_mode != inode->i_mode)) ||
(attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
return hsb->s_quiet ? 0 : error;
}
if (attr->ia_valid & ATTR_MODE) {
/* Only the 'w' bits can ever change and only all together. */
if (attr->ia_mode & S_IWUSR)
attr->ia_mode = inode->i_mode | S_IWUGO;
else
attr->ia_mode = inode->i_mode & ~S_IWUGO;
attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
}
error = inode_setattr(inode, attr);
if (error)
return error;
return 0;
}
static const struct file_operations hfs_file_operations = {
.llseek = generic_file_llseek,
.read = do_sync_read,
.aio_read = generic_file_aio_read,
.write = do_sync_write,
.aio_write = generic_file_aio_write,
.mmap = generic_file_mmap,
.sendfile = generic_file_sendfile,
.fsync = file_fsync,
.open = hfs_file_open,
.release = hfs_file_release,
};
static const struct inode_operations hfs_file_inode_operations = {
.lookup = hfs_file_lookup,
.truncate = hfs_file_truncate,
.setattr = hfs_inode_setattr,
.permission = hfs_permission,
.setxattr = hfs_setxattr,
.getxattr = hfs_getxattr,
.listxattr = hfs_listxattr,
};