| /* |
| * linux/fs/minix/namei.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| */ |
| |
| #include <linux/sched.h> |
| #include <linux/minix_fs.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <linux/stat.h> |
| #include <linux/fcntl.h> |
| #include <linux/errno.h> |
| |
| #include <asm/segment.h> |
| |
| /* |
| * comment out this line if you want names > info->s_namelen chars to be |
| * truncated. Else they will be disallowed (ENAMETOOLONG). |
| */ |
| /* #define NO_TRUNCATE */ |
| |
| static inline int namecompare(int len, int maxlen, |
| const char * name, const char * buffer) |
| { |
| if (len >= maxlen || !buffer[len]) { |
| unsigned char same; |
| __asm__("repe ; cmpsb ; setz %0" |
| :"=q" (same) |
| :"S" ((long) name),"D" ((long) buffer),"c" (len) |
| :"cx","di","si"); |
| return same; |
| } |
| return 0; |
| } |
| |
| /* |
| * ok, we cannot use strncmp, as the name is not in our data space. |
| * Thus we'll have to use minix_match. No big problem. Match also makes |
| * some sanity tests. |
| * |
| * NOTE! unlike strncmp, minix_match returns 1 for success, 0 for failure. |
| */ |
| static int minix_match(int len, const char * name, |
| struct buffer_head * bh, unsigned long * offset, |
| struct minix_sb_info * info) |
| { |
| struct minix_dir_entry * de; |
| |
| de = (struct minix_dir_entry *) (bh->b_data + *offset); |
| *offset += info->s_dirsize; |
| if (!de->inode || len > info->s_namelen) |
| return 0; |
| /* "" means "." ---> so paths like "/usr/lib//libc.a" work */ |
| if (!len && (de->name[0]=='.') && (de->name[1]=='\0')) |
| return 1; |
| return namecompare(len,info->s_namelen,name,de->name); |
| } |
| |
| /* |
| * minix_find_entry() |
| * |
| * finds an entry in the specified directory with the wanted name. It |
| * returns the cache buffer in which the entry was found, and the entry |
| * itself (as a parameter - res_dir). It does NOT read the inode of the |
| * entry - you'll have to do that yourself if you want to. |
| */ |
| static struct buffer_head * minix_find_entry(struct inode * dir, |
| const char * name, int namelen, struct minix_dir_entry ** res_dir) |
| { |
| unsigned long block, offset; |
| struct buffer_head * bh; |
| struct minix_sb_info * info; |
| |
| *res_dir = NULL; |
| if (!dir || !dir->i_sb) |
| return NULL; |
| info = &dir->i_sb->u.minix_sb; |
| if (namelen > info->s_namelen) { |
| #ifdef NO_TRUNCATE |
| return NULL; |
| #else |
| namelen = info->s_namelen; |
| #endif |
| } |
| bh = NULL; |
| block = offset = 0; |
| while (block*BLOCK_SIZE+offset < dir->i_size) { |
| if (!bh) { |
| bh = minix_bread(dir,block,0); |
| if (!bh) { |
| block++; |
| continue; |
| } |
| } |
| *res_dir = (struct minix_dir_entry *) (bh->b_data + offset); |
| if (minix_match(namelen,name,bh,&offset,info)) |
| return bh; |
| if (offset < bh->b_size) |
| continue; |
| brelse(bh); |
| bh = NULL; |
| offset = 0; |
| block++; |
| } |
| brelse(bh); |
| *res_dir = NULL; |
| return NULL; |
| } |
| |
| int minix_lookup(struct inode * dir,const char * name, int len, |
| struct inode ** result) |
| { |
| int ino; |
| struct minix_dir_entry * de; |
| struct buffer_head * bh; |
| |
| *result = NULL; |
| if (!dir) |
| return -ENOENT; |
| if (!S_ISDIR(dir->i_mode)) { |
| iput(dir); |
| return -ENOENT; |
| } |
| if (!(bh = minix_find_entry(dir,name,len,&de))) { |
| iput(dir); |
| return -ENOENT; |
| } |
| ino = de->inode; |
| brelse(bh); |
| if (!(*result = iget(dir->i_sb,ino))) { |
| iput(dir); |
| return -EACCES; |
| } |
| iput(dir); |
| return 0; |
| } |
| |
| /* |
| * minix_add_entry() |
| * |
| * adds a file entry to the specified directory, returning a possible |
| * error value if it fails. |
| * |
| * NOTE!! The inode part of 'de' is left at 0 - which means you |
| * may not sleep between calling this and putting something into |
| * the entry, as someone else might have used it while you slept. |
| */ |
| static int minix_add_entry(struct inode * dir, |
| const char * name, int namelen, |
| struct buffer_head ** res_buf, |
| struct minix_dir_entry ** res_dir) |
| { |
| int i; |
| unsigned long block, offset; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| struct minix_sb_info * info; |
| |
| *res_buf = NULL; |
| *res_dir = NULL; |
| if (!dir || !dir->i_sb) |
| return -ENOENT; |
| info = &dir->i_sb->u.minix_sb; |
| if (namelen > info->s_namelen) { |
| #ifdef NO_TRUNCATE |
| return -ENAMETOOLONG; |
| #else |
| namelen = info->s_namelen; |
| #endif |
| } |
| if (!namelen) |
| return -ENOENT; |
| bh = NULL; |
| block = offset = 0; |
| while (1) { |
| if (!bh) { |
| bh = minix_bread(dir,block,1); |
| if (!bh) |
| return -ENOSPC; |
| } |
| de = (struct minix_dir_entry *) (bh->b_data + offset); |
| offset += info->s_dirsize; |
| if (block*bh->b_size + offset > dir->i_size) { |
| de->inode = 0; |
| dir->i_size = block*bh->b_size + offset; |
| dir->i_dirt = 1; |
| dir->i_ctime = CURRENT_TIME; |
| } |
| if (de->inode) { |
| if (namecompare(namelen, info->s_namelen, name, de->name)) { |
| brelse(bh); |
| return -EEXIST; |
| } |
| } else { |
| dir->i_mtime = dir->i_ctime = CURRENT_TIME; |
| for (i = 0; i < info->s_namelen ; i++) |
| de->name[i] = (i < namelen) ? name[i] : 0; |
| bh->b_dirt = 1; |
| *res_dir = de; |
| break; |
| } |
| if (offset < bh->b_size) |
| continue; |
| brelse(bh); |
| bh = NULL; |
| offset = 0; |
| block++; |
| } |
| *res_buf = bh; |
| return 0; |
| } |
| |
| int minix_create(struct inode * dir,const char * name, int len, int mode, |
| struct inode ** result) |
| { |
| int error; |
| struct inode * inode; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| |
| *result = NULL; |
| if (!dir) |
| return -ENOENT; |
| inode = minix_new_inode(dir); |
| if (!inode) { |
| iput(dir); |
| return -ENOSPC; |
| } |
| inode->i_op = &minix_file_inode_operations; |
| inode->i_mode = mode; |
| inode->i_dirt = 1; |
| error = minix_add_entry(dir,name,len, &bh ,&de); |
| if (error) { |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| iput(dir); |
| return error; |
| } |
| de->inode = inode->i_ino; |
| bh->b_dirt = 1; |
| brelse(bh); |
| iput(dir); |
| *result = inode; |
| return 0; |
| } |
| |
| int minix_mknod(struct inode * dir, const char * name, int len, int mode, int rdev) |
| { |
| int error; |
| struct inode * inode; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| |
| if (!dir) |
| return -ENOENT; |
| bh = minix_find_entry(dir,name,len,&de); |
| if (bh) { |
| brelse(bh); |
| iput(dir); |
| return -EEXIST; |
| } |
| inode = minix_new_inode(dir); |
| if (!inode) { |
| iput(dir); |
| return -ENOSPC; |
| } |
| inode->i_uid = current->euid; |
| inode->i_mode = mode; |
| inode->i_op = NULL; |
| if (S_ISREG(inode->i_mode)) |
| inode->i_op = &minix_file_inode_operations; |
| else if (S_ISDIR(inode->i_mode)) { |
| inode->i_op = &minix_dir_inode_operations; |
| if (dir->i_mode & S_ISGID) |
| inode->i_mode |= S_ISGID; |
| } |
| else if (S_ISLNK(inode->i_mode)) |
| inode->i_op = &minix_symlink_inode_operations; |
| else if (S_ISCHR(inode->i_mode)) |
| inode->i_op = &chrdev_inode_operations; |
| else if (S_ISBLK(inode->i_mode)) |
| inode->i_op = &blkdev_inode_operations; |
| else if (S_ISFIFO(inode->i_mode)) |
| init_fifo(inode); |
| if (S_ISBLK(mode) || S_ISCHR(mode)) |
| inode->i_rdev = rdev; |
| inode->i_mtime = inode->i_atime = CURRENT_TIME; |
| inode->i_dirt = 1; |
| error = minix_add_entry(dir, name, len, &bh, &de); |
| if (error) { |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| iput(dir); |
| return error; |
| } |
| de->inode = inode->i_ino; |
| bh->b_dirt = 1; |
| brelse(bh); |
| iput(dir); |
| iput(inode); |
| return 0; |
| } |
| |
| int minix_mkdir(struct inode * dir, const char * name, int len, int mode) |
| { |
| int error; |
| struct inode * inode; |
| struct buffer_head * bh, *dir_block; |
| struct minix_dir_entry * de; |
| struct minix_sb_info * info; |
| |
| if (!dir || !dir->i_sb) { |
| iput(dir); |
| return -EINVAL; |
| } |
| info = &dir->i_sb->u.minix_sb; |
| bh = minix_find_entry(dir,name,len,&de); |
| if (bh) { |
| brelse(bh); |
| iput(dir); |
| return -EEXIST; |
| } |
| if (dir->i_nlink >= MINIX_LINK_MAX) { |
| iput(dir); |
| return -EMLINK; |
| } |
| inode = minix_new_inode(dir); |
| if (!inode) { |
| iput(dir); |
| return -ENOSPC; |
| } |
| inode->i_op = &minix_dir_inode_operations; |
| inode->i_size = 2 * info->s_dirsize; |
| inode->i_mtime = inode->i_atime = CURRENT_TIME; |
| dir_block = minix_bread(inode,0,1); |
| if (!dir_block) { |
| iput(dir); |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| return -ENOSPC; |
| } |
| de = (struct minix_dir_entry *) dir_block->b_data; |
| de->inode=inode->i_ino; |
| strcpy(de->name,"."); |
| de = (struct minix_dir_entry *) (dir_block->b_data + info->s_dirsize); |
| de->inode = dir->i_ino; |
| strcpy(de->name,".."); |
| inode->i_nlink = 2; |
| dir_block->b_dirt = 1; |
| brelse(dir_block); |
| inode->i_mode = S_IFDIR | (mode & 0777 & ~current->umask); |
| if (dir->i_mode & S_ISGID) |
| inode->i_mode |= S_ISGID; |
| inode->i_dirt = 1; |
| error = minix_add_entry(dir, name, len, &bh, &de); |
| if (error) { |
| iput(dir); |
| inode->i_nlink=0; |
| iput(inode); |
| return error; |
| } |
| de->inode = inode->i_ino; |
| bh->b_dirt = 1; |
| dir->i_nlink++; |
| dir->i_dirt = 1; |
| iput(dir); |
| iput(inode); |
| brelse(bh); |
| return 0; |
| } |
| |
| /* |
| * routine to check that the specified directory is empty (for rmdir) |
| */ |
| static int empty_dir(struct inode * inode) |
| { |
| unsigned int block, offset; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| struct minix_sb_info * info; |
| |
| if (!inode || !inode->i_sb) |
| return 1; |
| info = &inode->i_sb->u.minix_sb; |
| block = 0; |
| bh = NULL; |
| offset = 2*info->s_dirsize; |
| if (inode->i_size & (info->s_dirsize-1)) |
| goto bad_dir; |
| if (inode->i_size < offset) |
| goto bad_dir; |
| bh = minix_bread(inode,0,0); |
| if (!bh) |
| goto bad_dir; |
| de = (struct minix_dir_entry *) bh->b_data; |
| if (!de->inode || strcmp(de->name,".")) |
| goto bad_dir; |
| de = (struct minix_dir_entry *) (bh->b_data + info->s_dirsize); |
| if (!de->inode || strcmp(de->name,"..")) |
| goto bad_dir; |
| while (block*BLOCK_SIZE+offset < inode->i_size) { |
| if (!bh) { |
| bh = minix_bread(inode,block,0); |
| if (!bh) { |
| block++; |
| continue; |
| } |
| } |
| de = (struct minix_dir_entry *) (bh->b_data + offset); |
| offset += info->s_dirsize; |
| if (de->inode) { |
| brelse(bh); |
| return 0; |
| } |
| if (offset < bh->b_size) |
| continue; |
| brelse(bh); |
| bh = NULL; |
| offset = 0; |
| block++; |
| } |
| brelse(bh); |
| return 1; |
| bad_dir: |
| brelse(bh); |
| printk("Bad directory on device %04x\n",inode->i_dev); |
| return 1; |
| } |
| |
| int minix_rmdir(struct inode * dir, const char * name, int len) |
| { |
| int retval; |
| struct inode * inode; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| |
| inode = NULL; |
| bh = minix_find_entry(dir,name,len,&de); |
| retval = -ENOENT; |
| if (!bh) |
| goto end_rmdir; |
| retval = -EPERM; |
| if (!(inode = iget(dir->i_sb, de->inode))) |
| goto end_rmdir; |
| if ((dir->i_mode & S_ISVTX) && current->euid && |
| inode->i_uid != current->euid) |
| goto end_rmdir; |
| if (inode->i_dev != dir->i_dev) |
| goto end_rmdir; |
| if (inode == dir) /* we may not delete ".", but "../dir" is ok */ |
| goto end_rmdir; |
| if (!S_ISDIR(inode->i_mode)) { |
| retval = -ENOTDIR; |
| goto end_rmdir; |
| } |
| if (!empty_dir(inode)) { |
| retval = -ENOTEMPTY; |
| goto end_rmdir; |
| } |
| if (inode->i_count > 1) { |
| retval = -EBUSY; |
| goto end_rmdir; |
| } |
| if (inode->i_nlink != 2) |
| printk("empty directory has nlink!=2 (%d)\n",inode->i_nlink); |
| de->inode = 0; |
| bh->b_dirt = 1; |
| inode->i_nlink=0; |
| inode->i_dirt=1; |
| dir->i_nlink--; |
| dir->i_ctime = dir->i_mtime = CURRENT_TIME; |
| dir->i_dirt=1; |
| retval = 0; |
| end_rmdir: |
| iput(dir); |
| iput(inode); |
| brelse(bh); |
| return retval; |
| } |
| |
| int minix_unlink(struct inode * dir, const char * name, int len) |
| { |
| int retval; |
| struct inode * inode; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| |
| repeat: |
| retval = -ENOENT; |
| inode = NULL; |
| bh = minix_find_entry(dir,name,len,&de); |
| if (!bh) |
| goto end_unlink; |
| if (!(inode = iget(dir->i_sb, de->inode))) |
| goto end_unlink; |
| if (de->inode != inode->i_ino) { |
| iput(inode); |
| brelse(bh); |
| current->counter = 0; |
| schedule(); |
| goto repeat; |
| } |
| retval = -EPERM; |
| if ((dir->i_mode & S_ISVTX) && !suser() && |
| current->euid != inode->i_uid && |
| current->euid != dir->i_uid) |
| goto end_unlink; |
| if (S_ISDIR(inode->i_mode)) |
| goto end_unlink; |
| if (!inode->i_nlink) { |
| printk("Deleting nonexistent file (%04x:%d), %d\n", |
| inode->i_dev,inode->i_ino,inode->i_nlink); |
| inode->i_nlink=1; |
| } |
| de->inode = 0; |
| bh->b_dirt = 1; |
| dir->i_ctime = dir->i_mtime = CURRENT_TIME; |
| dir->i_dirt = 1; |
| inode->i_nlink--; |
| inode->i_ctime = CURRENT_TIME; |
| inode->i_dirt = 1; |
| retval = 0; |
| end_unlink: |
| brelse(bh); |
| iput(inode); |
| iput(dir); |
| return retval; |
| } |
| |
| int minix_symlink(struct inode * dir, const char * name, int len, const char * symname) |
| { |
| struct minix_dir_entry * de; |
| struct inode * inode = NULL; |
| struct buffer_head * bh = NULL, * name_block = NULL; |
| int i; |
| char c; |
| |
| if (!(inode = minix_new_inode(dir))) { |
| iput(dir); |
| return -ENOSPC; |
| } |
| inode->i_mode = S_IFLNK | 0777; |
| inode->i_op = &minix_symlink_inode_operations; |
| name_block = minix_bread(inode,0,1); |
| if (!name_block) { |
| iput(dir); |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| return -ENOSPC; |
| } |
| i = 0; |
| while (i < 1023 && (c=*(symname++))) |
| name_block->b_data[i++] = c; |
| name_block->b_data[i] = 0; |
| name_block->b_dirt = 1; |
| brelse(name_block); |
| inode->i_size = i; |
| inode->i_dirt = 1; |
| bh = minix_find_entry(dir,name,len,&de); |
| if (bh) { |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| brelse(bh); |
| iput(dir); |
| return -EEXIST; |
| } |
| i = minix_add_entry(dir, name, len, &bh, &de); |
| if (i) { |
| inode->i_nlink--; |
| inode->i_dirt = 1; |
| iput(inode); |
| iput(dir); |
| return i; |
| } |
| de->inode = inode->i_ino; |
| bh->b_dirt = 1; |
| brelse(bh); |
| iput(dir); |
| iput(inode); |
| return 0; |
| } |
| |
| int minix_link(struct inode * oldinode, struct inode * dir, const char * name, int len) |
| { |
| int error; |
| struct minix_dir_entry * de; |
| struct buffer_head * bh; |
| |
| if (S_ISDIR(oldinode->i_mode)) { |
| iput(oldinode); |
| iput(dir); |
| return -EPERM; |
| } |
| if (oldinode->i_nlink >= MINIX_LINK_MAX) { |
| iput(oldinode); |
| iput(dir); |
| return -EMLINK; |
| } |
| bh = minix_find_entry(dir,name,len,&de); |
| if (bh) { |
| brelse(bh); |
| iput(dir); |
| iput(oldinode); |
| return -EEXIST; |
| } |
| error = minix_add_entry(dir, name, len, &bh, &de); |
| if (error) { |
| iput(dir); |
| iput(oldinode); |
| return error; |
| } |
| de->inode = oldinode->i_ino; |
| bh->b_dirt = 1; |
| brelse(bh); |
| iput(dir); |
| oldinode->i_nlink++; |
| oldinode->i_ctime = CURRENT_TIME; |
| oldinode->i_dirt = 1; |
| iput(oldinode); |
| return 0; |
| } |
| |
| static int subdir(struct inode * new_inode, struct inode * old_inode) |
| { |
| int ino; |
| int result; |
| |
| new_inode->i_count++; |
| result = 0; |
| for (;;) { |
| if (new_inode == old_inode) { |
| result = 1; |
| break; |
| } |
| if (new_inode->i_dev != old_inode->i_dev) |
| break; |
| ino = new_inode->i_ino; |
| if (minix_lookup(new_inode,"..",2,&new_inode)) |
| break; |
| if (new_inode->i_ino == ino) |
| break; |
| } |
| iput(new_inode); |
| return result; |
| } |
| |
| #define PARENT_INO(buffer) \ |
| (((struct minix_dir_entry *) ((buffer)+info->s_dirsize))->inode) |
| |
| /* |
| * rename uses retrying to avoid race-conditions: at least they should be minimal. |
| * it tries to allocate all the blocks, then sanity-checks, and if the sanity- |
| * checks fail, it tries to restart itself again. Very practical - no changes |
| * are done until we know everything works ok.. and then all the changes can be |
| * done in one fell swoop when we have claimed all the buffers needed. |
| * |
| * Anybody can rename anything with this: the permission checks are left to the |
| * higher-level routines. |
| */ |
| static int do_minix_rename(struct inode * old_dir, const char * old_name, int old_len, |
| struct inode * new_dir, const char * new_name, int new_len) |
| { |
| struct inode * old_inode, * new_inode; |
| struct buffer_head * old_bh, * new_bh, * dir_bh; |
| struct minix_dir_entry * old_de, * new_de; |
| struct minix_sb_info * info; |
| int retval; |
| |
| info = &old_dir->i_sb->u.minix_sb; |
| goto start_up; |
| try_again: |
| brelse(old_bh); |
| brelse(new_bh); |
| brelse(dir_bh); |
| iput(old_inode); |
| iput(new_inode); |
| current->counter = 0; |
| schedule(); |
| start_up: |
| old_inode = new_inode = NULL; |
| old_bh = new_bh = dir_bh = NULL; |
| old_bh = minix_find_entry(old_dir,old_name,old_len,&old_de); |
| retval = -ENOENT; |
| if (!old_bh) |
| goto end_rename; |
| old_inode = iget(old_dir->i_sb, old_de->inode); |
| if (!old_inode) |
| goto end_rename; |
| retval = -EPERM; |
| if ((old_dir->i_mode & S_ISVTX) && |
| current->euid != old_inode->i_uid && |
| current->euid != old_dir->i_uid && !suser()) |
| goto end_rename; |
| new_bh = minix_find_entry(new_dir,new_name,new_len,&new_de); |
| if (new_bh) { |
| new_inode = iget(new_dir->i_sb, new_de->inode); |
| if (!new_inode) { |
| brelse(new_bh); |
| new_bh = NULL; |
| } |
| } |
| if (new_inode == old_inode) { |
| retval = 0; |
| goto end_rename; |
| } |
| if (new_inode && S_ISDIR(new_inode->i_mode)) { |
| retval = -EISDIR; |
| if (!S_ISDIR(old_inode->i_mode)) |
| goto end_rename; |
| retval = -EINVAL; |
| if (subdir(new_dir, old_inode)) |
| goto end_rename; |
| retval = -ENOTEMPTY; |
| if (!empty_dir(new_inode)) |
| goto end_rename; |
| retval = -EBUSY; |
| if (new_inode->i_count > 1) |
| goto end_rename; |
| } |
| retval = -EPERM; |
| if (new_inode && (new_dir->i_mode & S_ISVTX) && |
| current->euid != new_inode->i_uid && |
| current->euid != new_dir->i_uid && !suser()) |
| goto end_rename; |
| if (S_ISDIR(old_inode->i_mode)) { |
| retval = -ENOTDIR; |
| if (new_inode && !S_ISDIR(new_inode->i_mode)) |
| goto end_rename; |
| retval = -EINVAL; |
| if (subdir(new_dir, old_inode)) |
| goto end_rename; |
| retval = -EIO; |
| dir_bh = minix_bread(old_inode,0,0); |
| if (!dir_bh) |
| goto end_rename; |
| if (PARENT_INO(dir_bh->b_data) != old_dir->i_ino) |
| goto end_rename; |
| retval = -EMLINK; |
| if (!new_inode && new_dir->i_nlink >= MINIX_LINK_MAX) |
| goto end_rename; |
| } |
| if (!new_bh) { |
| retval = minix_add_entry(new_dir,new_name,new_len,&new_bh,&new_de); |
| if (retval) |
| goto end_rename; |
| } |
| /* sanity checking before doing the rename - avoid races */ |
| if (new_inode && (new_de->inode != new_inode->i_ino)) |
| goto try_again; |
| if (new_de->inode && !new_inode) |
| goto try_again; |
| if (old_de->inode != old_inode->i_ino) |
| goto try_again; |
| /* ok, that's it */ |
| old_de->inode = 0; |
| new_de->inode = old_inode->i_ino; |
| if (new_inode) { |
| new_inode->i_nlink--; |
| new_inode->i_dirt = 1; |
| } |
| old_bh->b_dirt = 1; |
| new_bh->b_dirt = 1; |
| if (dir_bh) { |
| PARENT_INO(dir_bh->b_data) = new_dir->i_ino; |
| dir_bh->b_dirt = 1; |
| old_dir->i_nlink--; |
| old_dir->i_dirt = 1; |
| if (new_inode) { |
| new_inode->i_nlink--; |
| new_inode->i_dirt = 1; |
| } else { |
| new_dir->i_nlink++; |
| new_dir->i_dirt = 1; |
| } |
| } |
| retval = 0; |
| end_rename: |
| brelse(dir_bh); |
| brelse(old_bh); |
| brelse(new_bh); |
| iput(old_inode); |
| iput(new_inode); |
| iput(old_dir); |
| iput(new_dir); |
| return retval; |
| } |
| |
| /* |
| * Ok, rename also locks out other renames, as they can change the parent of |
| * a directory, and we don't want any races. Other races are checked for by |
| * "do_rename()", which restarts if there are inconsistencies. |
| * |
| * Note that there is no race between different filesystems: it's only within |
| * the same device that races occur: many renames can happen at once, as long |
| * as they are on different partitions. |
| */ |
| int minix_rename(struct inode * old_dir, const char * old_name, int old_len, |
| struct inode * new_dir, const char * new_name, int new_len) |
| { |
| static struct wait_queue * wait = NULL; |
| static int lock = 0; |
| int result; |
| |
| while (lock) |
| sleep_on(&wait); |
| lock = 1; |
| result = do_minix_rename(old_dir, old_name, old_len, |
| new_dir, new_name, new_len); |
| lock = 0; |
| wake_up(&wait); |
| return result; |
| } |