diff options
Diffstat (limited to 'fs/jffs2/dir.c')
| -rw-r--r-- | fs/jffs2/dir.c | 878 |
1 files changed, 878 insertions, 0 deletions
diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c new file mode 100644 index 000000000..c0aabbcbf --- /dev/null +++ b/fs/jffs2/dir.c @@ -0,0 +1,878 @@ +/* + * 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 user_namespace *, 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 user_namespace *, struct inode *, + struct dentry *, const char *); +static int jffs2_mkdir (struct user_namespace *, struct inode *,struct dentry *, + umode_t); +static int jffs2_rmdir (struct inode *,struct dentry *); +static int jffs2_mknod (struct user_namespace *, struct inode *,struct dentry *, + umode_t,dev_t); +static int jffs2_rename (struct user_namespace *, 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_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 user_namespace *mnt_userns, 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 user_namespace *mnt_userns, 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 user_namespace *mnt_userns, 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 user_namespace *mnt_userns, 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 user_namespace *mnt_userns, + 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; +} + |