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673db054d7
linux/fs/jffs2/dir.c
Christian Brauner e18275ae55
fs: port ->rename() to pass mnt_idmap 
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00

879 lines
23 KiB
C
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/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include "jffs2_fs_i.h"
#include "jffs2_fs_sb.h"
#include <linux/time.h>
#include "nodelist.h"
static int jffs2_readdir (struct file *, struct dir_context *);
static int jffs2_create (struct mnt_idmap *, struct inode *,
struct dentry *, umode_t, bool);
static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
unsigned int);
static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
static int jffs2_unlink (struct inode *,struct dentry *);
static int jffs2_symlink (struct mnt_idmap *, struct inode *,
struct dentry *, const char *);
static int jffs2_mkdir (struct mnt_idmap *, struct inode *,struct dentry *,
umode_t);
static int jffs2_rmdir (struct inode *,struct dentry *);
static int jffs2_mknod (struct mnt_idmap *, struct inode *,struct dentry *,
umode_t,dev_t);
static int jffs2_rename (struct mnt_idmap *, struct inode *,
struct dentry *, struct inode *, struct dentry *,
unsigned int);
const struct file_operations jffs2_dir_operations =
{
.read = generic_read_dir,
.iterate_shared=jffs2_readdir,
.unlocked_ioctl=jffs2_ioctl,
.fsync = jffs2_fsync,
.llseek = generic_file_llseek,
};
const struct inode_operations jffs2_dir_inode_operations =
{
.create = jffs2_create,
.lookup = jffs2_lookup,
.link = jffs2_link,
.unlink = jffs2_unlink,
.symlink = jffs2_symlink,
.mkdir = jffs2_mkdir,
.rmdir = jffs2_rmdir,
.mknod = jffs2_mknod,
.rename = jffs2_rename,
.get_inode_acl = jffs2_get_acl,
.set_acl = jffs2_set_acl,
.setattr = jffs2_setattr,
.listxattr = jffs2_listxattr,
};
/***********************************************************************/
/* We keep the dirent list sorted in increasing order of name hash,
and we use the same hash function as the dentries. Makes this
nice and simple
*/
static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
unsigned int flags)
{
struct jffs2_inode_info *dir_f;
struct jffs2_full_dirent *fd = NULL, *fd_list;
uint32_t ino = 0;
struct inode *inode = NULL;
unsigned int nhash;
jffs2_dbg(1, "jffs2_lookup()\n");
if (target->d_name.len > JFFS2_MAX_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
dir_f = JFFS2_INODE_INFO(dir_i);
/* The 'nhash' on the fd_list is not the same as the dentry hash */
nhash = full_name_hash(NULL, target->d_name.name, target->d_name.len);
mutex_lock(&dir_f->sem);
/* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= nhash; fd_list = fd_list->next) {
if (fd_list->nhash == nhash &&
(!fd || fd_list->version > fd->version) &&
strlen(fd_list->name) == target->d_name.len &&
!strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
fd = fd_list;
}
}
if (fd)
ino = fd->ino;
mutex_unlock(&dir_f->sem);
if (ino) {
inode = jffs2_iget(dir_i->i_sb, ino);
if (IS_ERR(inode))
pr_warn("iget() failed for ino #%u\n", ino);
}
return d_splice_alias(inode, target);
}
/***********************************************************************/
static int jffs2_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_full_dirent *fd;
unsigned long curofs = 1;
jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino);
if (!dir_emit_dots(file, ctx))
return 0;
mutex_lock(&f->sem);
for (fd = f->dents; fd; fd = fd->next) {
curofs++;
/* First loop: curofs = 2; pos = 2 */
if (curofs < ctx->pos) {
jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos);
continue;
}
if (!fd->ino) {
jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
fd->name);
ctx->pos++;
continue;
}
jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
(unsigned long)ctx->pos, fd->name, fd->ino, fd->type);
if (!dir_emit(ctx, fd->name, strlen(fd->name), fd->ino, fd->type))
break;
ctx->pos++;
}
mutex_unlock(&f->sem);
return 0;
}
/***********************************************************************/
static int jffs2_create(struct mnt_idmap *idmap, struct inode *dir_i,
struct dentry *dentry, umode_t mode, bool excl)
{
struct jffs2_raw_inode *ri;
struct jffs2_inode_info *f, *dir_f;
struct jffs2_sb_info *c;
struct inode *inode;
int ret;
ri = jffs2_alloc_raw_inode();
if (!ri)
return -ENOMEM;
c = JFFS2_SB_INFO(dir_i->i_sb);
jffs2_dbg(1, "%s()\n", __func__);
inode = jffs2_new_inode(dir_i, mode, ri);
if (IS_ERR(inode)) {
jffs2_dbg(1, "jffs2_new_inode() failed\n");
jffs2_free_raw_inode(ri);
return PTR_ERR(inode);
}
inode->i_op = &jffs2_file_inode_operations;
inode->i_fop = &jffs2_file_operations;
inode->i_mapping->a_ops = &jffs2_file_address_operations;
inode->i_mapping->nrpages = 0;
f = JFFS2_INODE_INFO(inode);
dir_f = JFFS2_INODE_INFO(dir_i);
/* jffs2_do_create() will want to lock it, _after_ reserving
space and taking c-alloc_sem. If we keep it locked here,
lockdep gets unhappy (although it's a false positive;
nothing else will be looking at this inode yet so there's
no chance of AB-BA deadlock involving its f->sem). */
mutex_unlock(&f->sem);
ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name);
if (ret)
goto fail;
dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
jffs2_free_raw_inode(ri);
jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
__func__, inode->i_ino, inode->i_mode, inode->i_nlink,
f->inocache->pino_nlink, inode->i_mapping->nrpages);
d_instantiate_new(dentry, inode);
return 0;
fail:
iget_failed(inode);
jffs2_free_raw_inode(ri);
return ret;
}
/***********************************************************************/
static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(d_inode(dentry));
int ret;
uint32_t now = JFFS2_NOW();
ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
dentry->d_name.len, dead_f, now);
if (dead_f->inocache)
set_nlink(d_inode(dentry), dead_f->inocache->pino_nlink);
if (!ret)
dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
return ret;
}
/***********************************************************************/
static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_sb);
struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
int ret;
uint8_t type;
uint32_t now;
/* Don't let people make hard links to bad inodes. */
if (!f->inocache)
return -EIO;
if (d_is_dir(old_dentry))
return -EPERM;
/* XXX: This is ugly */
type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12;
if (!type) type = DT_REG;
now = JFFS2_NOW();
ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now);
if (!ret) {
mutex_lock(&f->sem);
set_nlink(d_inode(old_dentry), ++f->inocache->pino_nlink);
mutex_unlock(&f->sem);
d_instantiate(dentry, d_inode(old_dentry));
dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
ihold(d_inode(old_dentry));
}
return ret;
}
/***********************************************************************/
static int jffs2_symlink (struct mnt_idmap *idmap, struct inode *dir_i,
struct dentry *dentry, const char *target)
{
struct jffs2_inode_info *f, *dir_f;
struct jffs2_sb_info *c;
struct inode *inode;
struct jffs2_raw_inode *ri;
struct jffs2_raw_dirent *rd;
struct jffs2_full_dnode *fn;
struct jffs2_full_dirent *fd;
int namelen;
uint32_t alloclen;
int ret, targetlen = strlen(target);
/* FIXME: If you care. We'd need to use frags for the target
if it grows much more than this */
if (targetlen > 254)
return -ENAMETOOLONG;
ri = jffs2_alloc_raw_inode();
if (!ri)
return -ENOMEM;
c = JFFS2_SB_INFO(dir_i->i_sb);
/* Try to reserve enough space for both node and dirent.
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
return ret;
}
inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
return PTR_ERR(inode);
}
inode->i_op = &jffs2_symlink_inode_operations;
f = JFFS2_INODE_INFO(inode);
inode->i_size = targetlen;
ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
ri->compr = JFFS2_COMPR_NONE;
ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL);
jffs2_free_raw_inode(ri);
if (IS_ERR(fn)) {
/* Eeek. Wave bye bye */
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = PTR_ERR(fn);
goto fail;
}
/* We use f->target field to store the target path. */
f->target = kmemdup(target, targetlen + 1, GFP_KERNEL);
if (!f->target) {
pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1);
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = -ENOMEM;
goto fail;
}
inode->i_link = f->target;
jffs2_dbg(1, "%s(): symlink's target '%s' cached\n",
__func__, (char *)f->target);
/* No data here. Only a metadata node, which will be
obsoleted by the first data write
*/
f->metadata = fn;
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
if (ret)
goto fail;
ret = jffs2_init_acl_post(inode);
if (ret)
goto fail;
ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
if (ret)
goto fail;
rd = jffs2_alloc_raw_dirent();
if (!rd) {
/* Argh. Now we treat it like a normal delete */
jffs2_complete_reservation(c);
ret = -ENOMEM;
goto fail;
}
dir_f = JFFS2_INODE_INFO(dir_i);
mutex_lock(&dir_f->sem);
rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
rd->pino = cpu_to_je32(dir_i->i_ino);
rd->version = cpu_to_je32(++dir_f->highest_version);
rd->ino = cpu_to_je32(inode->i_ino);
rd->mctime = cpu_to_je32(JFFS2_NOW());
rd->nsize = namelen;
rd->type = DT_LNK;
rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
if (IS_ERR(fd)) {
/* dirent failed to write. Delete the inode normally
as if it were the final unlink() */
jffs2_complete_reservation(c);
jffs2_free_raw_dirent(rd);
mutex_unlock(&dir_f->sem);
ret = PTR_ERR(fd);
goto fail;
}
dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
jffs2_free_raw_dirent(rd);
/* Link the fd into the inode's list, obsoleting an old
one if necessary. */
jffs2_add_fd_to_list(c, fd, &dir_f->dents);
mutex_unlock(&dir_f->sem);
jffs2_complete_reservation(c);
d_instantiate_new(dentry, inode);
return 0;
fail:
iget_failed(inode);
return ret;
}
static int jffs2_mkdir (struct mnt_idmap *idmap, struct inode *dir_i,
struct dentry *dentry, umode_t mode)
{
struct jffs2_inode_info *f, *dir_f;
struct jffs2_sb_info *c;
struct inode *inode;
struct jffs2_raw_inode *ri;
struct jffs2_raw_dirent *rd;
struct jffs2_full_dnode *fn;
struct jffs2_full_dirent *fd;
int namelen;
uint32_t alloclen;
int ret;
mode |= S_IFDIR;
ri = jffs2_alloc_raw_inode();
if (!ri)
return -ENOMEM;
c = JFFS2_SB_INFO(dir_i->i_sb);
/* Try to reserve enough space for both node and dirent.
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
return ret;
}
inode = jffs2_new_inode(dir_i, mode, ri);
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
return PTR_ERR(inode);
}
inode->i_op = &jffs2_dir_inode_operations;
inode->i_fop = &jffs2_dir_operations;
f = JFFS2_INODE_INFO(inode);
/* Directories get nlink 2 at start */
set_nlink(inode, 2);
/* but ic->pino_nlink is the parent ino# */
f->inocache->pino_nlink = dir_i->i_ino;
ri->data_crc = cpu_to_je32(0);
ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
jffs2_free_raw_inode(ri);
if (IS_ERR(fn)) {
/* Eeek. Wave bye bye */
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = PTR_ERR(fn);
goto fail;
}
/* No data here. Only a metadata node, which will be
obsoleted by the first data write
*/
f->metadata = fn;
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
if (ret)
goto fail;
ret = jffs2_init_acl_post(inode);
if (ret)
goto fail;
ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
if (ret)
goto fail;
rd = jffs2_alloc_raw_dirent();
if (!rd) {
/* Argh. Now we treat it like a normal delete */
jffs2_complete_reservation(c);
ret = -ENOMEM;
goto fail;
}
dir_f = JFFS2_INODE_INFO(dir_i);
mutex_lock(&dir_f->sem);
rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
rd->pino = cpu_to_je32(dir_i->i_ino);
rd->version = cpu_to_je32(++dir_f->highest_version);
rd->ino = cpu_to_je32(inode->i_ino);
rd->mctime = cpu_to_je32(JFFS2_NOW());
rd->nsize = namelen;
rd->type = DT_DIR;
rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
if (IS_ERR(fd)) {
/* dirent failed to write. Delete the inode normally
as if it were the final unlink() */
jffs2_complete_reservation(c);
jffs2_free_raw_dirent(rd);
mutex_unlock(&dir_f->sem);
ret = PTR_ERR(fd);
goto fail;
}
dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
inc_nlink(dir_i);
jffs2_free_raw_dirent(rd);
/* Link the fd into the inode's list, obsoleting an old
one if necessary. */
jffs2_add_fd_to_list(c, fd, &dir_f->dents);
mutex_unlock(&dir_f->sem);
jffs2_complete_reservation(c);
d_instantiate_new(dentry, inode);
return 0;
fail:
iget_failed(inode);
return ret;
}
static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(dentry));
struct jffs2_full_dirent *fd;
int ret;
uint32_t now = JFFS2_NOW();
mutex_lock(&f->sem);
for (fd = f->dents ; fd; fd = fd->next) {
if (fd->ino) {
mutex_unlock(&f->sem);
return -ENOTEMPTY;
}
}
mutex_unlock(&f->sem);
ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
dentry->d_name.len, f, now);
if (!ret) {
dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
clear_nlink(d_inode(dentry));
drop_nlink(dir_i);
}
return ret;
}
static int jffs2_mknod (struct mnt_idmap *idmap, struct inode *dir_i,
struct dentry *dentry, umode_t mode, dev_t rdev)
{
struct jffs2_inode_info *f, *dir_f;
struct jffs2_sb_info *c;
struct inode *inode;
struct jffs2_raw_inode *ri;
struct jffs2_raw_dirent *rd;
struct jffs2_full_dnode *fn;
struct jffs2_full_dirent *fd;
int namelen;
union jffs2_device_node dev;
int devlen = 0;
uint32_t alloclen;
int ret;
ri = jffs2_alloc_raw_inode();
if (!ri)
return -ENOMEM;
c = JFFS2_SB_INFO(dir_i->i_sb);
if (S_ISBLK(mode) || S_ISCHR(mode))
devlen = jffs2_encode_dev(&dev, rdev);
/* Try to reserve enough space for both node and dirent.
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
return ret;
}
inode = jffs2_new_inode(dir_i, mode, ri);
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
return PTR_ERR(inode);
}
inode->i_op = &jffs2_file_inode_operations;
init_special_inode(inode, inode->i_mode, rdev);
f = JFFS2_INODE_INFO(inode);
ri->dsize = ri->csize = cpu_to_je32(devlen);
ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
ri->compr = JFFS2_COMPR_NONE;
ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL);
jffs2_free_raw_inode(ri);
if (IS_ERR(fn)) {
/* Eeek. Wave bye bye */
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = PTR_ERR(fn);
goto fail;
}
/* No data here. Only a metadata node, which will be
obsoleted by the first data write
*/
f->metadata = fn;
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
if (ret)
goto fail;
ret = jffs2_init_acl_post(inode);
if (ret)
goto fail;
ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
if (ret)
goto fail;
rd = jffs2_alloc_raw_dirent();
if (!rd) {
/* Argh. Now we treat it like a normal delete */
jffs2_complete_reservation(c);
ret = -ENOMEM;
goto fail;
}
dir_f = JFFS2_INODE_INFO(dir_i);
mutex_lock(&dir_f->sem);
rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
rd->pino = cpu_to_je32(dir_i->i_ino);
rd->version = cpu_to_je32(++dir_f->highest_version);
rd->ino = cpu_to_je32(inode->i_ino);
rd->mctime = cpu_to_je32(JFFS2_NOW());
rd->nsize = namelen;
/* XXX: This is ugly. */
rd->type = (mode & S_IFMT) >> 12;
rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
if (IS_ERR(fd)) {
/* dirent failed to write. Delete the inode normally
as if it were the final unlink() */
jffs2_complete_reservation(c);
jffs2_free_raw_dirent(rd);
mutex_unlock(&dir_f->sem);
ret = PTR_ERR(fd);
goto fail;
}
dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
jffs2_free_raw_dirent(rd);
/* Link the fd into the inode's list, obsoleting an old
one if necessary. */
jffs2_add_fd_to_list(c, fd, &dir_f->dents);
mutex_unlock(&dir_f->sem);
jffs2_complete_reservation(c);
d_instantiate_new(dentry, inode);
return 0;
fail:
iget_failed(inode);
return ret;
}
static int jffs2_rename (struct mnt_idmap *idmap,
struct inode *old_dir_i, struct dentry *old_dentry,
struct inode *new_dir_i, struct dentry *new_dentry,
unsigned int flags)
{
int ret;
struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
struct jffs2_inode_info *victim_f = NULL;
uint8_t type;
uint32_t now;
if (flags & ~RENAME_NOREPLACE)
return -EINVAL;
/* The VFS will check for us and prevent trying to rename a
* file over a directory and vice versa, but if it's a directory,
* the VFS can't check whether the victim is empty. The filesystem
* needs to do that for itself.
*/
if (d_really_is_positive(new_dentry)) {
victim_f = JFFS2_INODE_INFO(d_inode(new_dentry));
if (d_is_dir(new_dentry)) {
struct jffs2_full_dirent *fd;
mutex_lock(&victim_f->sem);
for (fd = victim_f->dents; fd; fd = fd->next) {
if (fd->ino) {
mutex_unlock(&victim_f->sem);
return -ENOTEMPTY;
}
}
mutex_unlock(&victim_f->sem);
}
}
/* XXX: We probably ought to alloc enough space for
both nodes at the same time. Writing the new link,
then getting -ENOSPC, is quite bad :)
*/
/* Make a hard link */
/* XXX: This is ugly */
type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12;
if (!type) type = DT_REG;
now = JFFS2_NOW();
ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
d_inode(old_dentry)->i_ino, type,
new_dentry->d_name.name, new_dentry->d_name.len, now);
if (ret)
return ret;
if (victim_f) {
/* There was a victim. Kill it off nicely */
if (d_is_dir(new_dentry))
clear_nlink(d_inode(new_dentry));
else
drop_nlink(d_inode(new_dentry));
/* Don't oops if the victim was a dirent pointing to an
inode which didn't exist. */
if (victim_f->inocache) {
mutex_lock(&victim_f->sem);
if (d_is_dir(new_dentry))
victim_f->inocache->pino_nlink = 0;
else
victim_f->inocache->pino_nlink--;
mutex_unlock(&victim_f->sem);
}
}
/* If it was a directory we moved, and there was no victim,
increase i_nlink on its new parent */
if (d_is_dir(old_dentry) && !victim_f)
inc_nlink(new_dir_i);
/* Unlink the original */
ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
/* We don't touch inode->i_nlink */
if (ret) {
/* Oh shit. We really ought to make a single node which can do both atomically */
struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
mutex_lock(&f->sem);
inc_nlink(d_inode(old_dentry));
if (f->inocache && !d_is_dir(old_dentry))
f->inocache->pino_nlink++;
mutex_unlock(&f->sem);
pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n",
__func__, ret);
/*
* We can't keep the target in dcache after that.
* For one thing, we can't afford dentry aliases for directories.
* For another, if there was a victim, we _can't_ set new inode
* for that sucker and we have to trigger mount eviction - the
* caller won't do it on its own since we are returning an error.
*/
d_invalidate(new_dentry);
new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
return ret;
}
if (d_is_dir(old_dentry))
drop_nlink(old_dir_i);
new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now);
return 0;
}
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