tmp_suning_uos_patched/fs/hpfs/dir.c
Arnd Bergmann 9a311b96c3 hpfs: remove the BKL
This removes the BKL in hpfs in a rather awful
way, by making the code only work on uniprocessor
systems without kernel preemption, as suggested
by Andi Kleen.

The HPFS code probably has close to zero remaining
users on current kernels, all archeological uses of
the file system can probably be done with the significant
restrictions.

The hpfs_lock/hpfs_unlock functions are left in the
code, sincen Mikulas has indicated that he is still
interested in fixing it in a better way.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: linux-fsdevel@vger.kernel.org
2011-03-02 22:27:36 +01:00

325 lines
8.4 KiB
C

/*
* linux/fs/hpfs/dir.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* directory VFS functions
*/
#include <linux/slab.h>
#include "hpfs_fn.h"
static int hpfs_dir_release(struct inode *inode, struct file *filp)
{
hpfs_lock(inode->i_sb);
hpfs_del_pos(inode, &filp->f_pos);
/*hpfs_write_if_changed(inode);*/
hpfs_unlock(inode->i_sb);
return 0;
}
/* This is slow, but it's not used often */
static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
{
loff_t new_off = off + (whence == 1 ? filp->f_pos : 0);
loff_t pos;
struct quad_buffer_head qbh;
struct inode *i = filp->f_path.dentry->d_inode;
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct super_block *s = i->i_sb;
hpfs_lock(s);
/*printk("dir lseek\n");*/
if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
mutex_lock(&i->i_mutex);
pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
while (pos != new_off) {
if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
else goto fail;
if (pos == 12) goto fail;
}
mutex_unlock(&i->i_mutex);
ok:
hpfs_unlock(s);
return filp->f_pos = new_off;
fail:
mutex_unlock(&i->i_mutex);
/*printk("illegal lseek: %016llx\n", new_off);*/
hpfs_unlock(s);
return -ESPIPE;
}
static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_path.dentry->d_inode;
struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
int lc;
long old_pos;
unsigned char *tempname;
int c1, c2 = 0;
int ret = 0;
hpfs_lock(inode->i_sb);
if (hpfs_sb(inode->i_sb)->sb_chk) {
if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
ret = -EFSERROR;
goto out;
}
if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
ret = -EFSERROR;
goto out;
}
}
if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
struct buffer_head *bh;
struct fnode *fno;
int e = 0;
if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
ret = -EIOERROR;
goto out;
}
if (!fno->dirflag) {
e = 1;
hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
(unsigned long)inode->i_ino);
}
if (hpfs_inode->i_dno != fno->u.external[0].disk_secno) {
e = 1;
hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, fno->u.external[0].disk_secno);
}
brelse(bh);
if (e) {
ret = -EFSERROR;
goto out;
}
}
lc = hpfs_sb(inode->i_sb)->sb_lowercase;
if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
goto out;
}
if (filp->f_pos == 13) {
ret = -ENOENT;
goto out;
}
while (1) {
again:
/* This won't work when cycle is longer than number of dirents
accepted by filldir, but what can I do?
maybe killall -9 ls helps */
if (hpfs_sb(inode->i_sb)->sb_chk)
if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
ret = -EFSERROR;
goto out;
}
if (filp->f_pos == 12)
goto out;
if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
printk("HPFS: warning: pos==%d\n",(int)filp->f_pos);
goto out;
}
if (filp->f_pos == 0) {
if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
goto out;
filp->f_pos = 11;
}
if (filp->f_pos == 11) {
if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
goto out;
filp->f_pos = 1;
}
if (filp->f_pos == 1) {
filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
hpfs_add_pos(inode, &filp->f_pos);
filp->f_version = inode->i_version;
}
old_pos = filp->f_pos;
if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
ret = -EIOERROR;
goto out;
}
if (de->first || de->last) {
if (hpfs_sb(inode->i_sb)->sb_chk) {
if (de->first && !de->last && (de->namelen != 2
|| de ->name[0] != 1 || de->name[1] != 1))
hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
if (de->last && (de->namelen != 1 || de ->name[0] != 255))
hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);
}
hpfs_brelse4(&qbh);
goto again;
}
tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
if (filldir(dirent, tempname, de->namelen, old_pos, de->fnode, DT_UNKNOWN) < 0) {
filp->f_pos = old_pos;
if (tempname != de->name) kfree(tempname);
hpfs_brelse4(&qbh);
goto out;
}
if (tempname != de->name) kfree(tempname);
hpfs_brelse4(&qbh);
}
out:
hpfs_unlock(inode->i_sb);
return ret;
}
/*
* lookup. Search the specified directory for the specified name, set
* *result to the corresponding inode.
*
* lookup uses the inode number to tell read_inode whether it is reading
* the inode of a directory or a file -- file ino's are odd, directory
* ino's are even. read_inode avoids i/o for file inodes; everything
* needed is up here in the directory. (And file fnodes are out in
* the boondocks.)
*
* - M.P.: this is over, sometimes we've got to read file's fnode for eas
* inode numbers are just fnode sector numbers; iget lock is used
* to tell read_inode to read fnode or not.
*/
struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
const unsigned char *name = dentry->d_name.name;
unsigned len = dentry->d_name.len;
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
ino_t ino;
int err;
struct inode *result = NULL;
struct hpfs_inode_info *hpfs_result;
hpfs_lock(dir->i_sb);
if ((err = hpfs_chk_name(name, &len))) {
if (err == -ENAMETOOLONG) {
hpfs_unlock(dir->i_sb);
return ERR_PTR(-ENAMETOOLONG);
}
goto end_add;
}
/*
* '.' and '..' will never be passed here.
*/
de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
/*
* This is not really a bailout, just means file not found.
*/
if (!de) goto end;
/*
* Get inode number, what we're after.
*/
ino = de->fnode;
/*
* Go find or make an inode.
*/
result = iget_locked(dir->i_sb, ino);
if (!result) {
hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
goto bail1;
}
if (result->i_state & I_NEW) {
hpfs_init_inode(result);
if (de->directory)
hpfs_read_inode(result);
else if (de->ea_size && hpfs_sb(dir->i_sb)->sb_eas)
hpfs_read_inode(result);
else {
result->i_mode |= S_IFREG;
result->i_mode &= ~0111;
result->i_op = &hpfs_file_iops;
result->i_fop = &hpfs_file_ops;
result->i_nlink = 1;
}
unlock_new_inode(result);
}
hpfs_result = hpfs_i(result);
if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
hpfs_decide_conv(result, name, len);
if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
hpfs_error(result->i_sb, "ACLs or XPERM found. This is probably HPFS386. This driver doesn't support it now. Send me some info on these structures");
goto bail1;
}
/*
* Fill in the info from the directory if this is a newly created
* inode.
*/
if (!result->i_ctime.tv_sec) {
if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, de->creation_date)))
result->i_ctime.tv_sec = 1;
result->i_ctime.tv_nsec = 0;
result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, de->write_date);
result->i_mtime.tv_nsec = 0;
result->i_atime.tv_sec = local_to_gmt(dir->i_sb, de->read_date);
result->i_atime.tv_nsec = 0;
hpfs_result->i_ea_size = de->ea_size;
if (!hpfs_result->i_ea_mode && de->read_only)
result->i_mode &= ~0222;
if (!de->directory) {
if (result->i_size == -1) {
result->i_size = de->file_size;
result->i_data.a_ops = &hpfs_aops;
hpfs_i(result)->mmu_private = result->i_size;
/*
* i_blocks should count the fnode and any anodes.
* We count 1 for the fnode and don't bother about
* anodes -- the disk heads are on the directory band
* and we want them to stay there.
*/
result->i_blocks = 1 + ((result->i_size + 511) >> 9);
}
}
}
hpfs_brelse4(&qbh);
/*
* Made it.
*/
end:
end_add:
hpfs_unlock(dir->i_sb);
d_add(dentry, result);
return NULL;
/*
* Didn't.
*/
bail1:
hpfs_brelse4(&qbh);
/*bail:*/
hpfs_unlock(dir->i_sb);
return ERR_PTR(-ENOENT);
}
const struct file_operations hpfs_dir_ops =
{
.llseek = hpfs_dir_lseek,
.read = generic_read_dir,
.readdir = hpfs_readdir,
.release = hpfs_dir_release,
.fsync = hpfs_file_fsync,
};