diff options
author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /fs/sysv | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'fs/sysv')
-rw-r--r-- | fs/sysv/Kconfig | 36 | ||||
-rw-r--r-- | fs/sysv/Makefile | 8 | ||||
-rw-r--r-- | fs/sysv/balloc.c | 239 | ||||
-rw-r--r-- | fs/sysv/dir.c | 377 | ||||
-rw-r--r-- | fs/sysv/file.c | 58 | ||||
-rw-r--r-- | fs/sysv/ialloc.c | 234 | ||||
-rw-r--r-- | fs/sysv/inode.c | 381 | ||||
-rw-r--r-- | fs/sysv/itree.c | 494 | ||||
-rw-r--r-- | fs/sysv/namei.c | 301 | ||||
-rw-r--r-- | fs/sysv/super.c | 590 | ||||
-rw-r--r-- | fs/sysv/symlink.c | 20 | ||||
-rw-r--r-- | fs/sysv/sysv.h | 248 |
12 files changed, 2986 insertions, 0 deletions
diff --git a/fs/sysv/Kconfig b/fs/sysv/Kconfig new file mode 100644 index 00000000..33aeb4b7 --- /dev/null +++ b/fs/sysv/Kconfig @@ -0,0 +1,36 @@ +config SYSV_FS + tristate "System V/Xenix/V7/Coherent file system support" + depends on BLOCK + help + SCO, Xenix and Coherent are commercial Unix systems for Intel + machines, and Version 7 was used on the DEC PDP-11. Saying Y + here would allow you to read from their floppies and hard disk + partitions. + + If you have floppies or hard disk partitions like that, it is likely + that they contain binaries from those other Unix systems; in order + to run these binaries, you will want to install linux-abi which is + a set of kernel modules that lets you run SCO, Xenix, Wyse, + UnixWare, Dell Unix and System V programs under Linux. It is + available via FTP (user: ftp) from + <ftp://ftp.openlinux.org/pub/people/hch/linux-abi/>). + NOTE: that will work only for binaries from Intel-based systems; + PDP ones will have to wait until somebody ports Linux to -11 ;-) + + If you only intend to mount files from some other Unix over the + network using NFS, you don't need the System V file system support + (but you need NFS file system support obviously). + + Note that this option is generally not needed for floppies, since a + good portable way to transport files and directories between unixes + (and even other operating systems) is given by the tar program ("man + tar" or preferably "info tar"). Note also that this option has + nothing whatsoever to do with the option "System V IPC". Read about + the System V file system in + <file:Documentation/filesystems/sysv-fs.txt>. + Saying Y here will enlarge your kernel by about 27 KB. + + To compile this as a module, choose M here: the module will be called + sysv. + + If you haven't heard about all of this before, it's safe to say N. diff --git a/fs/sysv/Makefile b/fs/sysv/Makefile new file mode 100644 index 00000000..3591f9d7 --- /dev/null +++ b/fs/sysv/Makefile @@ -0,0 +1,8 @@ +# +# Makefile for the Linux SystemV/Coherent filesystem routines. +# + +obj-$(CONFIG_SYSV_FS) += sysv.o + +sysv-objs := ialloc.o balloc.o inode.o itree.o file.o dir.o \ + namei.o super.o symlink.o diff --git a/fs/sysv/balloc.c b/fs/sysv/balloc.c new file mode 100644 index 00000000..9a6ad96a --- /dev/null +++ b/fs/sysv/balloc.c @@ -0,0 +1,239 @@ +/* + * linux/fs/sysv/balloc.c + * + * minix/bitmap.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * ext/freelists.c + * Copyright (C) 1992 Remy Card (card@masi.ibp.fr) + * + * xenix/alloc.c + * Copyright (C) 1992 Doug Evans + * + * coh/alloc.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/balloc.c + * Copyright (C) 1993 Bruno Haible + * + * This file contains code for allocating/freeing blocks. + */ + +#include <linux/buffer_head.h> +#include <linux/string.h> +#include "sysv.h" + +/* We don't trust the value of + sb->sv_sbd2->s_tfree = *sb->sv_free_blocks + but we nevertheless keep it up to date. */ + +static inline sysv_zone_t *get_chunk(struct super_block *sb, struct buffer_head *bh) +{ + char *bh_data = bh->b_data; + + if (SYSV_SB(sb)->s_type == FSTYPE_SYSV4) + return (sysv_zone_t*)(bh_data+4); + else + return (sysv_zone_t*)(bh_data+2); +} + +/* NOTE NOTE NOTE: nr is a block number _as_ _stored_ _on_ _disk_ */ + +void sysv_free_block(struct super_block * sb, sysv_zone_t nr) +{ + struct sysv_sb_info * sbi = SYSV_SB(sb); + struct buffer_head * bh; + sysv_zone_t *blocks = sbi->s_bcache; + unsigned count; + unsigned block = fs32_to_cpu(sbi, nr); + + /* + * This code does not work at all for AFS (it has a bitmap + * free list). As AFS is supposed to be read-only no one + * should call this for an AFS filesystem anyway... + */ + if (sbi->s_type == FSTYPE_AFS) + return; + + if (block < sbi->s_firstdatazone || block >= sbi->s_nzones) { + printk("sysv_free_block: trying to free block not in datazone\n"); + return; + } + + lock_super(sb); + count = fs16_to_cpu(sbi, *sbi->s_bcache_count); + + if (count > sbi->s_flc_size) { + printk("sysv_free_block: flc_count > flc_size\n"); + unlock_super(sb); + return; + } + /* If the free list head in super-block is full, it is copied + * into this block being freed, ditto if it's completely empty + * (applies only on Coherent). + */ + if (count == sbi->s_flc_size || count == 0) { + block += sbi->s_block_base; + bh = sb_getblk(sb, block); + if (!bh) { + printk("sysv_free_block: getblk() failed\n"); + unlock_super(sb); + return; + } + memset(bh->b_data, 0, sb->s_blocksize); + *(__fs16*)bh->b_data = cpu_to_fs16(sbi, count); + memcpy(get_chunk(sb,bh), blocks, count * sizeof(sysv_zone_t)); + mark_buffer_dirty(bh); + set_buffer_uptodate(bh); + brelse(bh); + count = 0; + } + sbi->s_bcache[count++] = nr; + + *sbi->s_bcache_count = cpu_to_fs16(sbi, count); + fs32_add(sbi, sbi->s_free_blocks, 1); + dirty_sb(sb); + unlock_super(sb); +} + +sysv_zone_t sysv_new_block(struct super_block * sb) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + unsigned int block; + sysv_zone_t nr; + struct buffer_head * bh; + unsigned count; + + lock_super(sb); + count = fs16_to_cpu(sbi, *sbi->s_bcache_count); + + if (count == 0) /* Applies only to Coherent FS */ + goto Enospc; + nr = sbi->s_bcache[--count]; + if (nr == 0) /* Applies only to Xenix FS, SystemV FS */ + goto Enospc; + + block = fs32_to_cpu(sbi, nr); + + *sbi->s_bcache_count = cpu_to_fs16(sbi, count); + + if (block < sbi->s_firstdatazone || block >= sbi->s_nzones) { + printk("sysv_new_block: new block %d is not in data zone\n", + block); + goto Enospc; + } + + if (count == 0) { /* the last block continues the free list */ + unsigned count; + + block += sbi->s_block_base; + if (!(bh = sb_bread(sb, block))) { + printk("sysv_new_block: cannot read free-list block\n"); + /* retry this same block next time */ + *sbi->s_bcache_count = cpu_to_fs16(sbi, 1); + goto Enospc; + } + count = fs16_to_cpu(sbi, *(__fs16*)bh->b_data); + if (count > sbi->s_flc_size) { + printk("sysv_new_block: free-list block with >flc_size entries\n"); + brelse(bh); + goto Enospc; + } + *sbi->s_bcache_count = cpu_to_fs16(sbi, count); + memcpy(sbi->s_bcache, get_chunk(sb, bh), + count * sizeof(sysv_zone_t)); + brelse(bh); + } + /* Now the free list head in the superblock is valid again. */ + fs32_add(sbi, sbi->s_free_blocks, -1); + dirty_sb(sb); + unlock_super(sb); + return nr; + +Enospc: + unlock_super(sb); + return 0; +} + +unsigned long sysv_count_free_blocks(struct super_block * sb) +{ + struct sysv_sb_info * sbi = SYSV_SB(sb); + int sb_count; + int count; + struct buffer_head * bh = NULL; + sysv_zone_t *blocks; + unsigned block; + int n; + + /* + * This code does not work at all for AFS (it has a bitmap + * free list). As AFS is supposed to be read-only we just + * lie and say it has no free block at all. + */ + if (sbi->s_type == FSTYPE_AFS) + return 0; + + lock_super(sb); + sb_count = fs32_to_cpu(sbi, *sbi->s_free_blocks); + + if (0) + goto trust_sb; + + /* this causes a lot of disk traffic ... */ + count = 0; + n = fs16_to_cpu(sbi, *sbi->s_bcache_count); + blocks = sbi->s_bcache; + while (1) { + sysv_zone_t zone; + if (n > sbi->s_flc_size) + goto E2big; + zone = 0; + while (n && (zone = blocks[--n]) != 0) + count++; + if (zone == 0) + break; + + block = fs32_to_cpu(sbi, zone); + if (bh) + brelse(bh); + + if (block < sbi->s_firstdatazone || block >= sbi->s_nzones) + goto Einval; + block += sbi->s_block_base; + bh = sb_bread(sb, block); + if (!bh) + goto Eio; + n = fs16_to_cpu(sbi, *(__fs16*)bh->b_data); + blocks = get_chunk(sb, bh); + } + if (bh) + brelse(bh); + if (count != sb_count) + goto Ecount; +done: + unlock_super(sb); + return count; + +Einval: + printk("sysv_count_free_blocks: new block %d is not in data zone\n", + block); + goto trust_sb; +Eio: + printk("sysv_count_free_blocks: cannot read free-list block\n"); + goto trust_sb; +E2big: + printk("sysv_count_free_blocks: >flc_size entries in free-list block\n"); + if (bh) + brelse(bh); +trust_sb: + count = sb_count; + goto done; +Ecount: + printk("sysv_count_free_blocks: free block count was %d, " + "correcting to %d\n", sb_count, count); + if (!(sb->s_flags & MS_RDONLY)) { + *sbi->s_free_blocks = cpu_to_fs32(sbi, count); + dirty_sb(sb); + } + goto done; +} diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c new file mode 100644 index 00000000..a77c4215 --- /dev/null +++ b/fs/sysv/dir.c @@ -0,0 +1,377 @@ +/* + * linux/fs/sysv/dir.c + * + * minix/dir.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * coh/dir.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/dir.c + * Copyright (C) 1993 Bruno Haible + * + * SystemV/Coherent directory handling functions + */ + +#include <linux/pagemap.h> +#include <linux/highmem.h> +#include <linux/swap.h> +#include "sysv.h" + +static int sysv_readdir(struct file *, void *, filldir_t); + +const struct file_operations sysv_dir_operations = { + .llseek = generic_file_llseek, + .read = generic_read_dir, + .readdir = sysv_readdir, + .fsync = generic_file_fsync, +}; + +static inline void dir_put_page(struct page *page) +{ + kunmap(page); + page_cache_release(page); +} + +static inline unsigned long dir_pages(struct inode *inode) +{ + return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT; +} + +static int dir_commit_chunk(struct page *page, loff_t pos, unsigned len) +{ + struct address_space *mapping = page->mapping; + struct inode *dir = mapping->host; + int err = 0; + + block_write_end(NULL, mapping, pos, len, len, page, NULL); + if (pos+len > dir->i_size) { + i_size_write(dir, pos+len); + mark_inode_dirty(dir); + } + if (IS_DIRSYNC(dir)) + err = write_one_page(page, 1); + else + unlock_page(page); + return err; +} + +static struct page * dir_get_page(struct inode *dir, unsigned long n) +{ + struct address_space *mapping = dir->i_mapping; + struct page *page = read_mapping_page(mapping, n, NULL); + if (!IS_ERR(page)) + kmap(page); + return page; +} + +static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir) +{ + unsigned long pos = filp->f_pos; + struct inode *inode = filp->f_path.dentry->d_inode; + struct super_block *sb = inode->i_sb; + unsigned offset = pos & ~PAGE_CACHE_MASK; + unsigned long n = pos >> PAGE_CACHE_SHIFT; + unsigned long npages = dir_pages(inode); + + pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1); + if (pos >= inode->i_size) + goto done; + + for ( ; n < npages; n++, offset = 0) { + char *kaddr, *limit; + struct sysv_dir_entry *de; + struct page *page = dir_get_page(inode, n); + + if (IS_ERR(page)) + continue; + kaddr = (char *)page_address(page); + de = (struct sysv_dir_entry *)(kaddr+offset); + limit = kaddr + PAGE_CACHE_SIZE - SYSV_DIRSIZE; + for ( ;(char*)de <= limit; de++) { + char *name = de->name; + int over; + + if (!de->inode) + continue; + + offset = (char *)de - kaddr; + + over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN), + ((loff_t)n<<PAGE_CACHE_SHIFT) | offset, + fs16_to_cpu(SYSV_SB(sb), de->inode), + DT_UNKNOWN); + if (over) { + dir_put_page(page); + goto done; + } + } + dir_put_page(page); + } + +done: + filp->f_pos = ((loff_t)n << PAGE_CACHE_SHIFT) | offset; + return 0; +} + +/* compare strings: name[0..len-1] (not zero-terminated) and + * buffer[0..] (filled with zeroes up to buffer[0..maxlen-1]) + */ +static inline int namecompare(int len, int maxlen, + const char * name, const char * buffer) +{ + if (len < maxlen && buffer[len]) + return 0; + return !memcmp(name, buffer, len); +} + +/* + * sysv_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. + */ +struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_page) +{ + const char * name = dentry->d_name.name; + int namelen = dentry->d_name.len; + struct inode * dir = dentry->d_parent->d_inode; + unsigned long start, n; + unsigned long npages = dir_pages(dir); + struct page *page = NULL; + struct sysv_dir_entry *de; + + *res_page = NULL; + + start = SYSV_I(dir)->i_dir_start_lookup; + if (start >= npages) + start = 0; + n = start; + + do { + char *kaddr; + page = dir_get_page(dir, n); + if (!IS_ERR(page)) { + kaddr = (char*)page_address(page); + de = (struct sysv_dir_entry *) kaddr; + kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE; + for ( ; (char *) de <= kaddr ; de++) { + if (!de->inode) + continue; + if (namecompare(namelen, SYSV_NAMELEN, + name, de->name)) + goto found; + } + dir_put_page(page); + } + + if (++n >= npages) + n = 0; + } while (n != start); + + return NULL; + +found: + SYSV_I(dir)->i_dir_start_lookup = n; + *res_page = page; + return de; +} + +int sysv_add_link(struct dentry *dentry, struct inode *inode) +{ + struct inode *dir = dentry->d_parent->d_inode; + const char * name = dentry->d_name.name; + int namelen = dentry->d_name.len; + struct page *page = NULL; + struct sysv_dir_entry * de; + unsigned long npages = dir_pages(dir); + unsigned long n; + char *kaddr; + loff_t pos; + int err; + + /* We take care of directory expansion in the same loop */ + for (n = 0; n <= npages; n++) { + page = dir_get_page(dir, n); + err = PTR_ERR(page); + if (IS_ERR(page)) + goto out; + kaddr = (char*)page_address(page); + de = (struct sysv_dir_entry *)kaddr; + kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE; + while ((char *)de <= kaddr) { + if (!de->inode) + goto got_it; + err = -EEXIST; + if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) + goto out_page; + de++; + } + dir_put_page(page); + } + BUG(); + return -EINVAL; + +got_it: + pos = page_offset(page) + + (char*)de - (char*)page_address(page); + lock_page(page); + err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE); + if (err) + goto out_unlock; + memcpy (de->name, name, namelen); + memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2); + de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino); + err = dir_commit_chunk(page, pos, SYSV_DIRSIZE); + dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(dir); +out_page: + dir_put_page(page); +out: + return err; +out_unlock: + unlock_page(page); + goto out_page; +} + +int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page) +{ + struct inode *inode = page->mapping->host; + char *kaddr = (char*)page_address(page); + loff_t pos = page_offset(page) + (char *)de - kaddr; + int err; + + lock_page(page); + err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE); + BUG_ON(err); + de->inode = 0; + err = dir_commit_chunk(page, pos, SYSV_DIRSIZE); + dir_put_page(page); + inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); + return err; +} + +int sysv_make_empty(struct inode *inode, struct inode *dir) +{ + struct page *page = grab_cache_page(inode->i_mapping, 0); + struct sysv_dir_entry * de; + char *base; + int err; + + if (!page) + return -ENOMEM; + err = sysv_prepare_chunk(page, 0, 2 * SYSV_DIRSIZE); + if (err) { + unlock_page(page); + goto fail; + } + kmap(page); + + base = (char*)page_address(page); + memset(base, 0, PAGE_CACHE_SIZE); + + de = (struct sysv_dir_entry *) base; + de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino); + strcpy(de->name,"."); + de++; + de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino); + strcpy(de->name,".."); + + kunmap(page); + err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE); +fail: + page_cache_release(page); + return err; +} + +/* + * routine to check that the specified directory is empty (for rmdir) + */ +int sysv_empty_dir(struct inode * inode) +{ + struct super_block *sb = inode->i_sb; + struct page *page = NULL; + unsigned long i, npages = dir_pages(inode); + + for (i = 0; i < npages; i++) { + char *kaddr; + struct sysv_dir_entry * de; + page = dir_get_page(inode, i); + + if (IS_ERR(page)) + continue; + + kaddr = (char *)page_address(page); + de = (struct sysv_dir_entry *)kaddr; + kaddr += PAGE_CACHE_SIZE-SYSV_DIRSIZE; + + for ( ;(char *)de <= kaddr; de++) { + if (!de->inode) + continue; + /* check for . and .. */ + if (de->name[0] != '.') + goto not_empty; + if (!de->name[1]) { + if (de->inode == cpu_to_fs16(SYSV_SB(sb), + inode->i_ino)) + continue; + goto not_empty; + } + if (de->name[1] != '.' || de->name[2]) + goto not_empty; + } + dir_put_page(page); + } + return 1; + +not_empty: + dir_put_page(page); + return 0; +} + +/* Releases the page */ +void sysv_set_link(struct sysv_dir_entry *de, struct page *page, + struct inode *inode) +{ + struct inode *dir = page->mapping->host; + loff_t pos = page_offset(page) + + (char *)de-(char*)page_address(page); + int err; + + lock_page(page); + err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE); + BUG_ON(err); + de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino); + err = dir_commit_chunk(page, pos, SYSV_DIRSIZE); + dir_put_page(page); + dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(dir); +} + +struct sysv_dir_entry * sysv_dotdot (struct inode *dir, struct page **p) +{ + struct page *page = dir_get_page(dir, 0); + struct sysv_dir_entry *de = NULL; + + if (!IS_ERR(page)) { + de = (struct sysv_dir_entry*) page_address(page) + 1; + *p = page; + } + return de; +} + +ino_t sysv_inode_by_name(struct dentry *dentry) +{ + struct page *page; + struct sysv_dir_entry *de = sysv_find_entry (dentry, &page); + ino_t res = 0; + + if (de) { + res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode); + dir_put_page(page); + } + return res; +} diff --git a/fs/sysv/file.c b/fs/sysv/file.c new file mode 100644 index 00000000..0a659395 --- /dev/null +++ b/fs/sysv/file.c @@ -0,0 +1,58 @@ +/* + * linux/fs/sysv/file.c + * + * minix/file.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * coh/file.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/file.c + * Copyright (C) 1993 Bruno Haible + * + * SystemV/Coherent regular file handling primitives + */ + +#include "sysv.h" + +/* + * We have mostly NULLs here: the current defaults are OK for + * the coh filesystem. + */ +const struct file_operations sysv_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, + .fsync = generic_file_fsync, + .splice_read = generic_file_splice_read, +}; + +static int sysv_setattr(struct dentry *dentry, struct iattr *attr) +{ + struct inode *inode = dentry->d_inode; + int error; + + error = inode_change_ok(inode, attr); + if (error) + return error; + + if ((attr->ia_valid & ATTR_SIZE) && + attr->ia_size != i_size_read(inode)) { + error = vmtruncate(inode, attr->ia_size); + if (error) + return error; + } + + setattr_copy(inode, attr); + mark_inode_dirty(inode); + return 0; +} + +const struct inode_operations sysv_file_inode_operations = { + .truncate = sysv_truncate, + .setattr = sysv_setattr, + .getattr = sysv_getattr, +}; diff --git a/fs/sysv/ialloc.c b/fs/sysv/ialloc.c new file mode 100644 index 00000000..0c96c98b --- /dev/null +++ b/fs/sysv/ialloc.c @@ -0,0 +1,234 @@ +/* + * linux/fs/sysv/ialloc.c + * + * minix/bitmap.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * ext/freelists.c + * Copyright (C) 1992 Remy Card (card@masi.ibp.fr) + * + * xenix/alloc.c + * Copyright (C) 1992 Doug Evans + * + * coh/alloc.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/ialloc.c + * Copyright (C) 1993 Bruno Haible + * + * This file contains code for allocating/freeing inodes. + */ + +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/sched.h> +#include <linux/stat.h> +#include <linux/string.h> +#include <linux/buffer_head.h> +#include <linux/writeback.h> +#include "sysv.h" + +/* We don't trust the value of + sb->sv_sbd2->s_tinode = *sb->sv_sb_total_free_inodes + but we nevertheless keep it up to date. */ + +/* An inode on disk is considered free if both i_mode == 0 and i_nlink == 0. */ + +/* return &sb->sv_sb_fic_inodes[i] = &sbd->s_inode[i]; */ +static inline sysv_ino_t * +sv_sb_fic_inode(struct super_block * sb, unsigned int i) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + + if (sbi->s_bh1 == sbi->s_bh2) + return &sbi->s_sb_fic_inodes[i]; + else { + /* 512 byte Xenix FS */ + unsigned int offset = offsetof(struct xenix_super_block, s_inode[i]); + if (offset < 512) + return (sysv_ino_t*)(sbi->s_sbd1 + offset); + else + return (sysv_ino_t*)(sbi->s_sbd2 + offset); + } +} + +struct sysv_inode * +sysv_raw_inode(struct super_block *sb, unsigned ino, struct buffer_head **bh) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + struct sysv_inode *res; + int block = sbi->s_firstinodezone + sbi->s_block_base; + + block += (ino-1) >> sbi->s_inodes_per_block_bits; + *bh = sb_bread(sb, block); + if (!*bh) + return NULL; + res = (struct sysv_inode *)(*bh)->b_data; + return res + ((ino-1) & sbi->s_inodes_per_block_1); +} + +static int refill_free_cache(struct super_block *sb) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + struct buffer_head * bh; + struct sysv_inode * raw_inode; + int i = 0, ino; + + ino = SYSV_ROOT_INO+1; + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) + goto out; + while (ino <= sbi->s_ninodes) { + if (raw_inode->i_mode == 0 && raw_inode->i_nlink == 0) { + *sv_sb_fic_inode(sb,i++) = cpu_to_fs16(SYSV_SB(sb), ino); + if (i == sbi->s_fic_size) + break; + } + if ((ino++ & sbi->s_inodes_per_block_1) == 0) { + brelse(bh); + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) + goto out; + } else + raw_inode++; + } + brelse(bh); +out: + return i; +} + +void sysv_free_inode(struct inode * inode) +{ + struct super_block *sb = inode->i_sb; + struct sysv_sb_info *sbi = SYSV_SB(sb); + unsigned int ino; + struct buffer_head * bh; + struct sysv_inode * raw_inode; + unsigned count; + + sb = inode->i_sb; + ino = inode->i_ino; + if (ino <= SYSV_ROOT_INO || ino > sbi->s_ninodes) { + printk("sysv_free_inode: inode 0,1,2 or nonexistent inode\n"); + return; + } + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) { + printk("sysv_free_inode: unable to read inode block on device " + "%s\n", inode->i_sb->s_id); + return; + } + lock_super(sb); + count = fs16_to_cpu(sbi, *sbi->s_sb_fic_count); + if (count < sbi->s_fic_size) { + *sv_sb_fic_inode(sb,count++) = cpu_to_fs16(sbi, ino); + *sbi->s_sb_fic_count = cpu_to_fs16(sbi, count); + } + fs16_add(sbi, sbi->s_sb_total_free_inodes, 1); + dirty_sb(sb); + memset(raw_inode, 0, sizeof(struct sysv_inode)); + mark_buffer_dirty(bh); + unlock_super(sb); + brelse(bh); +} + +struct inode * sysv_new_inode(const struct inode * dir, mode_t mode) +{ + struct super_block *sb = dir->i_sb; + struct sysv_sb_info *sbi = SYSV_SB(sb); + struct inode *inode; + sysv_ino_t ino; + unsigned count; + struct writeback_control wbc = { + .sync_mode = WB_SYNC_NONE + }; + + inode = new_inode(sb); + if (!inode) + return ERR_PTR(-ENOMEM); + + lock_super(sb); + count = fs16_to_cpu(sbi, *sbi->s_sb_fic_count); + if (count == 0 || (*sv_sb_fic_inode(sb,count-1) == 0)) { + count = refill_free_cache(sb); + if (count == 0) { + iput(inode); + unlock_super(sb); + return ERR_PTR(-ENOSPC); + } + } + /* Now count > 0. */ + ino = *sv_sb_fic_inode(sb,--count); + *sbi->s_sb_fic_count = cpu_to_fs16(sbi, count); + fs16_add(sbi, sbi->s_sb_total_free_inodes, -1); + dirty_sb(sb); + inode_init_owner(inode, dir, mode); + inode->i_ino = fs16_to_cpu(sbi, ino); + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; + inode->i_blocks = 0; + memset(SYSV_I(inode)->i_data, 0, sizeof(SYSV_I(inode)->i_data)); + SYSV_I(inode)->i_dir_start_lookup = 0; + insert_inode_hash(inode); + mark_inode_dirty(inode); + + sysv_write_inode(inode, &wbc); /* ensure inode not allocated again */ + mark_inode_dirty(inode); /* cleared by sysv_write_inode() */ + /* That's it. */ + unlock_super(sb); + return inode; +} + +unsigned long sysv_count_free_inodes(struct super_block * sb) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + struct buffer_head * bh; + struct sysv_inode * raw_inode; + int ino, count, sb_count; + + lock_super(sb); + + sb_count = fs16_to_cpu(sbi, *sbi->s_sb_total_free_inodes); + + if (0) + goto trust_sb; + + /* this causes a lot of disk traffic ... */ + count = 0; + ino = SYSV_ROOT_INO+1; + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) + goto Eio; + while (ino <= sbi->s_ninodes) { + if (raw_inode->i_mode == 0 && raw_inode->i_nlink == 0) + count++; + if ((ino++ & sbi->s_inodes_per_block_1) == 0) { + brelse(bh); + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) + goto Eio; + } else + raw_inode++; + } + brelse(bh); + if (count != sb_count) + goto Einval; +out: + unlock_super(sb); + return count; + +Einval: + printk("sysv_count_free_inodes: " + "free inode count was %d, correcting to %d\n", + sb_count, count); + if (!(sb->s_flags & MS_RDONLY)) { + *sbi->s_sb_total_free_inodes = cpu_to_fs16(SYSV_SB(sb), count); + dirty_sb(sb); + } + goto out; + +Eio: + printk("sysv_count_free_inodes: unable to read inode table\n"); +trust_sb: + count = sb_count; + goto out; +} diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c new file mode 100644 index 00000000..0630eb96 --- /dev/null +++ b/fs/sysv/inode.c @@ -0,0 +1,381 @@ +/* + * linux/fs/sysv/inode.c + * + * minix/inode.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * xenix/inode.c + * Copyright (C) 1992 Doug Evans + * + * coh/inode.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/inode.c + * Copyright (C) 1993 Paul B. Monday + * + * sysv/inode.c + * Copyright (C) 1993 Bruno Haible + * Copyright (C) 1997, 1998 Krzysztof G. Baranowski + * + * This file contains code for allocating/freeing inodes and for read/writing + * the superblock. + */ + +#include <linux/highuid.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/buffer_head.h> +#include <linux/vfs.h> +#include <linux/writeback.h> +#include <linux/namei.h> +#include <asm/byteorder.h> +#include "sysv.h" + +static int sysv_sync_fs(struct super_block *sb, int wait) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + unsigned long time = get_seconds(), old_time; + + lock_super(sb); + + /* + * If we are going to write out the super block, + * then attach current time stamp. + * But if the filesystem was marked clean, keep it clean. + */ + sb->s_dirt = 0; + old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); + if (sbi->s_type == FSTYPE_SYSV4) { + if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) + *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); + *sbi->s_sb_time = cpu_to_fs32(sbi, time); + mark_buffer_dirty(sbi->s_bh2); + } + + unlock_super(sb); + + return 0; +} + +static void sysv_write_super(struct super_block *sb) +{ + if (!(sb->s_flags & MS_RDONLY)) + sysv_sync_fs(sb, 1); + else + sb->s_dirt = 0; +} + +static int sysv_remount(struct super_block *sb, int *flags, char *data) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + lock_super(sb); + if (sbi->s_forced_ro) + *flags |= MS_RDONLY; + if (*flags & MS_RDONLY) + sysv_write_super(sb); + unlock_super(sb); + return 0; +} + +static void sysv_put_super(struct super_block *sb) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + + if (sb->s_dirt) + sysv_write_super(sb); + + if (!(sb->s_flags & MS_RDONLY)) { + /* XXX ext2 also updates the state here */ + mark_buffer_dirty(sbi->s_bh1); + if (sbi->s_bh1 != sbi->s_bh2) + mark_buffer_dirty(sbi->s_bh2); + } + + brelse(sbi->s_bh1); + if (sbi->s_bh1 != sbi->s_bh2) + brelse(sbi->s_bh2); + + kfree(sbi); +} + +static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + struct sysv_sb_info *sbi = SYSV_SB(sb); + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + + buf->f_type = sb->s_magic; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = sbi->s_ndatazones; + buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); + buf->f_files = sbi->s_ninodes; + buf->f_ffree = sysv_count_free_inodes(sb); + buf->f_namelen = SYSV_NAMELEN; + buf->f_fsid.val[0] = (u32)id; + buf->f_fsid.val[1] = (u32)(id >> 32); + return 0; +} + +/* + * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 + */ +static inline void read3byte(struct sysv_sb_info *sbi, + unsigned char * from, unsigned char * to) +{ + if (sbi->s_bytesex == BYTESEX_PDP) { + to[0] = from[0]; + to[1] = 0; + to[2] = from[1]; + to[3] = from[2]; + } else if (sbi->s_bytesex == BYTESEX_LE) { + to[0] = from[0]; + to[1] = from[1]; + to[2] = from[2]; + to[3] = 0; + } else { + to[0] = 0; + to[1] = from[0]; + to[2] = from[1]; + to[3] = from[2]; + } +} + +static inline void write3byte(struct sysv_sb_info *sbi, + unsigned char * from, unsigned char * to) +{ + if (sbi->s_bytesex == BYTESEX_PDP) { + to[0] = from[0]; + to[1] = from[2]; + to[2] = from[3]; + } else if (sbi->s_bytesex == BYTESEX_LE) { + to[0] = from[0]; + to[1] = from[1]; + to[2] = from[2]; + } else { + to[0] = from[1]; + to[1] = from[2]; + to[2] = from[3]; + } +} + +static const struct inode_operations sysv_symlink_inode_operations = { + .readlink = generic_readlink, + .follow_link = page_follow_link_light, + .put_link = page_put_link, + .getattr = sysv_getattr, +}; + +void sysv_set_inode(struct inode *inode, dev_t rdev) +{ + if (S_ISREG(inode->i_mode)) { + inode->i_op = &sysv_file_inode_operations; + inode->i_fop = &sysv_file_operations; + inode->i_mapping->a_ops = &sysv_aops; + } else if (S_ISDIR(inode->i_mode)) { + inode->i_op = &sysv_dir_inode_operations; + inode->i_fop = &sysv_dir_operations; + inode->i_mapping->a_ops = &sysv_aops; + } else if (S_ISLNK(inode->i_mode)) { + if (inode->i_blocks) { + inode->i_op = &sysv_symlink_inode_operations; + inode->i_mapping->a_ops = &sysv_aops; + } else { + inode->i_op = &sysv_fast_symlink_inode_operations; + nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size, + sizeof(SYSV_I(inode)->i_data) - 1); + } + } else + init_special_inode(inode, inode->i_mode, rdev); +} + +struct inode *sysv_iget(struct super_block *sb, unsigned int ino) +{ + struct sysv_sb_info * sbi = SYSV_SB(sb); + struct buffer_head * bh; + struct sysv_inode * raw_inode; + struct sysv_inode_info * si; + struct inode *inode; + unsigned int block; + + if (!ino || ino > sbi->s_ninodes) { + printk("Bad inode number on dev %s: %d is out of range\n", + sb->s_id, ino); + return ERR_PTR(-EIO); + } + + inode = iget_locked(sb, ino); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) { + printk("Major problem: unable to read inode from dev %s\n", + inode->i_sb->s_id); + goto bad_inode; + } + /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ + inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); + inode->i_uid = (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid); + inode->i_gid = (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid); + inode->i_nlink = fs16_to_cpu(sbi, raw_inode->i_nlink); + inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); + inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); + inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); + inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); + inode->i_ctime.tv_nsec = 0; + inode->i_atime.tv_nsec = 0; + inode->i_mtime.tv_nsec = 0; + inode->i_blocks = 0; + + si = SYSV_I(inode); + for (block = 0; block < 10+1+1+1; block++) + read3byte(sbi, &raw_inode->i_data[3*block], + (u8 *)&si->i_data[block]); + brelse(bh); + si->i_dir_start_lookup = 0; + if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) + sysv_set_inode(inode, + old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); + else + sysv_set_inode(inode, 0); + unlock_new_inode(inode); + return inode; + +bad_inode: + iget_failed(inode); + return ERR_PTR(-EIO); +} + +static int __sysv_write_inode(struct inode *inode, int wait) +{ + struct super_block * sb = inode->i_sb; + struct sysv_sb_info * sbi = SYSV_SB(sb); + struct buffer_head * bh; + struct sysv_inode * raw_inode; + struct sysv_inode_info * si; + unsigned int ino, block; + int err = 0; + + ino = inode->i_ino; + if (!ino || ino > sbi->s_ninodes) { + printk("Bad inode number on dev %s: %d is out of range\n", + inode->i_sb->s_id, ino); + return -EIO; + } + raw_inode = sysv_raw_inode(sb, ino, &bh); + if (!raw_inode) { + printk("unable to read i-node block\n"); + return -EIO; + } + + raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); + raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(inode->i_uid)); + raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(inode->i_gid)); + raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); + raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); + raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); + raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); + raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); + + si = SYSV_I(inode); + if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) + si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); + for (block = 0; block < 10+1+1+1; block++) + write3byte(sbi, (u8 *)&si->i_data[block], + &raw_inode->i_data[3*block]); + mark_buffer_dirty(bh); + if (wait) { + sync_dirty_buffer(bh); + if (buffer_req(bh) && !buffer_uptodate(bh)) { + printk ("IO error syncing sysv inode [%s:%08x]\n", + sb->s_id, ino); + err = -EIO; + } + } + brelse(bh); + return 0; +} + +int sysv_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + return __sysv_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); +} + +int sysv_sync_inode(struct inode *inode) +{ + return __sysv_write_inode(inode, 1); +} + +static void sysv_evict_inode(struct inode *inode) +{ + truncate_inode_pages(&inode->i_data, 0); + if (!inode->i_nlink) { + inode->i_size = 0; + sysv_truncate(inode); + } + invalidate_inode_buffers(inode); + end_writeback(inode); + if (!inode->i_nlink) + sysv_free_inode(inode); +} + +static struct kmem_cache *sysv_inode_cachep; + +static struct inode *sysv_alloc_inode(struct super_block *sb) +{ + struct sysv_inode_info *si; + + si = kmem_cache_alloc(sysv_inode_cachep, GFP_KERNEL); + if (!si) + return NULL; + return &si->vfs_inode; +} + +static void sysv_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + INIT_LIST_HEAD(&inode->i_dentry); + kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); +} + +static void sysv_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, sysv_i_callback); +} + +static void init_once(void *p) +{ + struct sysv_inode_info *si = (struct sysv_inode_info *)p; + + inode_init_once(&si->vfs_inode); +} + +const struct super_operations sysv_sops = { + .alloc_inode = sysv_alloc_inode, + .destroy_inode = sysv_destroy_inode, + .write_inode = sysv_write_inode, + .evict_inode = sysv_evict_inode, + .put_super = sysv_put_super, + .write_super = sysv_write_super, + .sync_fs = sysv_sync_fs, + .remount_fs = sysv_remount, + .statfs = sysv_statfs, +}; + +int __init sysv_init_icache(void) +{ + sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", + sizeof(struct sysv_inode_info), 0, + SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, + init_once); + if (!sysv_inode_cachep) + return -ENOMEM; + return 0; +} + +void sysv_destroy_icache(void) +{ + kmem_cache_destroy(sysv_inode_cachep); +} diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c new file mode 100644 index 00000000..fa8d43c9 --- /dev/null +++ b/fs/sysv/itree.c @@ -0,0 +1,494 @@ +/* + * linux/fs/sysv/itree.c + * + * Handling of indirect blocks' trees. + * AV, Sep--Dec 2000 + */ + +#include <linux/buffer_head.h> +#include <linux/mount.h> +#include <linux/string.h> +#include "sysv.h" + +enum {DIRECT = 10, DEPTH = 4}; /* Have triple indirect */ + +static inline void dirty_indirect(struct buffer_head *bh, struct inode *inode) +{ + mark_buffer_dirty_inode(bh, inode); + if (IS_SYNC(inode)) + sync_dirty_buffer(bh); +} + +static int block_to_path(struct inode *inode, long block, int offsets[DEPTH]) +{ + struct super_block *sb = inode->i_sb; + struct sysv_sb_info *sbi = SYSV_SB(sb); + int ptrs_bits = sbi->s_ind_per_block_bits; + unsigned long indirect_blocks = sbi->s_ind_per_block, + double_blocks = sbi->s_ind_per_block_2; + int n = 0; + + if (block < 0) { + printk("sysv_block_map: block < 0\n"); + } else if (block < DIRECT) { + offsets[n++] = block; + } else if ( (block -= DIRECT) < indirect_blocks) { + offsets[n++] = DIRECT; + offsets[n++] = block; + } else if ((block -= indirect_blocks) < double_blocks) { + offsets[n++] = DIRECT+1; + offsets[n++] = block >> ptrs_bits; + offsets[n++] = block & (indirect_blocks - 1); + } else if (((block -= double_blocks) >> (ptrs_bits * 2)) < indirect_blocks) { + offsets[n++] = DIRECT+2; + offsets[n++] = block >> (ptrs_bits * 2); + offsets[n++] = (block >> ptrs_bits) & (indirect_blocks - 1); + offsets[n++] = block & (indirect_blocks - 1); + } else { + /* nothing */; + } + return n; +} + +static inline int block_to_cpu(struct sysv_sb_info *sbi, sysv_zone_t nr) +{ + return sbi->s_block_base + fs32_to_cpu(sbi, nr); +} + +typedef struct { + sysv_zone_t *p; + sysv_zone_t key; + struct buffer_head *bh; +} Indirect; + +static DEFINE_RWLOCK(pointers_lock); + +static inline void add_chain(Indirect *p, struct buffer_head *bh, sysv_zone_t *v) +{ + p->key = *(p->p = v); + p->bh = bh; +} + +static inline int verify_chain(Indirect *from, Indirect *to) +{ + while (from <= to && from->key == *from->p) + from++; + return (from > to); +} + +static inline sysv_zone_t *block_end(struct buffer_head *bh) +{ + return (sysv_zone_t*)((char*)bh->b_data + bh->b_size); +} + +/* + * Requires read_lock(&pointers_lock) or write_lock(&pointers_lock) + */ +static Indirect *get_branch(struct inode *inode, + int depth, + int offsets[], + Indirect chain[], + int *err) +{ + struct super_block *sb = inode->i_sb; + Indirect *p = chain; + struct buffer_head *bh; + + *err = 0; + add_chain(chain, NULL, SYSV_I(inode)->i_data + *offsets); + if (!p->key) + goto no_block; + while (--depth) { + int block = block_to_cpu(SYSV_SB(sb), p->key); + bh = sb_bread(sb, block); + if (!bh) + goto failure; + if (!verify_chain(chain, p)) + goto changed; + add_chain(++p, bh, (sysv_zone_t*)bh->b_data + *++offsets); + if (!p->key) + goto no_block; + } + return NULL; + +changed: + brelse(bh); + *err = -EAGAIN; + goto no_block; +failure: + *err = -EIO; +no_block: + return p; +} + +static int alloc_branch(struct inode *inode, + int num, + int *offsets, + Indirect *branch) +{ + int blocksize = inode->i_sb->s_blocksize; + int n = 0; + int i; + + branch[0].key = sysv_new_block(inode->i_sb); + if (branch[0].key) for (n = 1; n < num; n++) { + struct buffer_head *bh; + int parent; + /* Allocate the next block */ + branch[n].key = sysv_new_block(inode->i_sb); + if (!branch[n].key) + break; + /* + * Get buffer_head for parent block, zero it out and set + * the pointer to new one, then send parent to disk. + */ + parent = block_to_cpu(SYSV_SB(inode->i_sb), branch[n-1].key); + bh = sb_getblk(inode->i_sb, parent); + lock_buffer(bh); + memset(bh->b_data, 0, blocksize); + branch[n].bh = bh; + branch[n].p = (sysv_zone_t*) bh->b_data + offsets[n]; + *branch[n].p = branch[n].key; + set_buffer_uptodate(bh); + unlock_buffer(bh); + dirty_indirect(bh, inode); + } + if (n == num) + return 0; + + /* Allocation failed, free what we already allocated */ + for (i = 1; i < n; i++) + bforget(branch[i].bh); + for (i = 0; i < n; i++) + sysv_free_block(inode->i_sb, branch[i].key); + return -ENOSPC; +} + +static inline int splice_branch(struct inode *inode, + Indirect chain[], + Indirect *where, + int num) +{ + int i; + + /* Verify that place we are splicing to is still there and vacant */ + write_lock(&pointers_lock); + if (!verify_chain(chain, where-1) || *where->p) + goto changed; + *where->p = where->key; + write_unlock(&pointers_lock); + + inode->i_ctime = CURRENT_TIME_SEC; + + /* had we spliced it onto indirect block? */ + if (where->bh) + dirty_indirect(where->bh, inode); + + if (IS_SYNC(inode)) + sysv_sync_inode(inode); + else + mark_inode_dirty(inode); + return 0; + +changed: + write_unlock(&pointers_lock); + for (i = 1; i < num; i++) + bforget(where[i].bh); + for (i = 0; i < num; i++) + sysv_free_block(inode->i_sb, where[i].key); + return -EAGAIN; +} + +static int get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) +{ + int err = -EIO; + int offsets[DEPTH]; + Indirect chain[DEPTH]; + struct super_block *sb = inode->i_sb; + Indirect *partial; + int left; + int depth = block_to_path(inode, iblock, offsets); + + if (depth == 0) + goto out; + +reread: + read_lock(&pointers_lock); + partial = get_branch(inode, depth, offsets, chain, &err); + read_unlock(&pointers_lock); + + /* Simplest case - block found, no allocation needed */ + if (!partial) { +got_it: + map_bh(bh_result, sb, block_to_cpu(SYSV_SB(sb), + chain[depth-1].key)); + /* Clean up and exit */ + partial = chain+depth-1; /* the whole chain */ + goto cleanup; + } + + /* Next simple case - plain lookup or failed read of indirect block */ + if (!create || err == -EIO) { +cleanup: + while (partial > chain) { + brelse(partial->bh); + partial--; + } +out: + return err; + } + + /* + * Indirect block might be removed by truncate while we were + * reading it. Handling of that case (forget what we've got and + * reread) is taken out of the main path. + */ + if (err == -EAGAIN) + goto changed; + + left = (chain + depth) - partial; + err = alloc_branch(inode, left, offsets+(partial-chain), partial); + if (err) + goto cleanup; + + if (splice_branch(inode, chain, partial, left) < 0) + goto changed; + + set_buffer_new(bh_result); + goto got_it; + +changed: + while (partial > chain) { + brelse(partial->bh); + partial--; + } + goto reread; +} + +static inline int all_zeroes(sysv_zone_t *p, sysv_zone_t *q) +{ + while (p < q) + if (*p++) + return 0; + return 1; +} + +static Indirect *find_shared(struct inode *inode, + int depth, + int offsets[], + Indirect chain[], + sysv_zone_t *top) +{ + Indirect *partial, *p; + int k, err; + + *top = 0; + for (k = depth; k > 1 && !offsets[k-1]; k--) + ; + + write_lock(&pointers_lock); + partial = get_branch(inode, k, offsets, chain, &err); + if (!partial) + partial = chain + k-1; + /* + * If the branch acquired continuation since we've looked at it - + * fine, it should all survive and (new) top doesn't belong to us. + */ + if (!partial->key && *partial->p) { + write_unlock(&pointers_lock); + goto no_top; + } + for (p=partial; p>chain && all_zeroes((sysv_zone_t*)p->bh->b_data,p->p); p--) + ; + /* + * OK, we've found the last block that must survive. The rest of our + * branch should be detached before unlocking. However, if that rest + * of branch is all ours and does not grow immediately from the inode + * it's easier to cheat and just decrement partial->p. + */ + if (p == chain + k - 1 && p > chain) { + p->p--; + } else { + *top = *p->p; + *p->p = 0; + } + write_unlock(&pointers_lock); + + while (partial > p) { + brelse(partial->bh); + partial--; + } +no_top: + return partial; +} + +static inline void free_data(struct inode *inode, sysv_zone_t *p, sysv_zone_t *q) +{ + for ( ; p < q ; p++) { + sysv_zone_t nr = *p; + if (nr) { + *p = 0; + sysv_free_block(inode->i_sb, nr); + mark_inode_dirty(inode); + } + } +} + +static void free_branches(struct inode *inode, sysv_zone_t *p, sysv_zone_t *q, int depth) +{ + struct buffer_head * bh; + struct super_block *sb = inode->i_sb; + + if (depth--) { + for ( ; p < q ; p++) { + int block; + sysv_zone_t nr = *p; + if (!nr) + continue; + *p = 0; + block = block_to_cpu(SYSV_SB(sb), nr); + bh = sb_bread(sb, block); + if (!bh) + continue; + free_branches(inode, (sysv_zone_t*)bh->b_data, + block_end(bh), depth); + bforget(bh); + sysv_free_block(sb, nr); + mark_inode_dirty(inode); + } + } else + free_data(inode, p, q); +} + +void sysv_truncate (struct inode * inode) +{ + sysv_zone_t *i_data = SYSV_I(inode)->i_data; + int offsets[DEPTH]; + Indirect chain[DEPTH]; + Indirect *partial; + sysv_zone_t nr = 0; + int n; + long iblock; + unsigned blocksize; + + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || + S_ISLNK(inode->i_mode))) + return; + + blocksize = inode->i_sb->s_blocksize; + iblock = (inode->i_size + blocksize-1) + >> inode->i_sb->s_blocksize_bits; + + block_truncate_page(inode->i_mapping, inode->i_size, get_block); + + n = block_to_path(inode, iblock, offsets); + if (n == 0) + return; + + if (n == 1) { + free_data(inode, i_data+offsets[0], i_data + DIRECT); + goto do_indirects; + } + + partial = find_shared(inode, n, offsets, chain, &nr); + /* Kill the top of shared branch (already detached) */ + if (nr) { + if (partial == chain) + mark_inode_dirty(inode); + else + dirty_indirect(partial->bh, inode); + free_branches(inode, &nr, &nr+1, (chain+n-1) - partial); + } + /* Clear the ends of indirect blocks on the shared branch */ + while (partial > chain) { + free_branches(inode, partial->p + 1, block_end(partial->bh), + (chain+n-1) - partial); + dirty_indirect(partial->bh, inode); + brelse (partial->bh); + partial--; + } +do_indirects: + /* Kill the remaining (whole) subtrees (== subtrees deeper than...) */ + while (n < DEPTH) { + nr = i_data[DIRECT + n - 1]; + if (nr) { + i_data[DIRECT + n - 1] = 0; + mark_inode_dirty(inode); + free_branches(inode, &nr, &nr+1, n); + } + n++; + } + inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; + if (IS_SYNC(inode)) + sysv_sync_inode (inode); + else + mark_inode_dirty(inode); +} + +static unsigned sysv_nblocks(struct super_block *s, loff_t size) +{ + struct sysv_sb_info *sbi = SYSV_SB(s); + int ptrs_bits = sbi->s_ind_per_block_bits; + unsigned blocks, res, direct = DIRECT, i = DEPTH; + blocks = (size + s->s_blocksize - 1) >> s->s_blocksize_bits; + res = blocks; + while (--i && blocks > direct) { + blocks = ((blocks - direct - 1) >> ptrs_bits) + 1; + res += blocks; + direct = 1; + } + return blocks; +} + +int sysv_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) +{ + struct super_block *s = mnt->mnt_sb; + generic_fillattr(dentry->d_inode, stat); + stat->blocks = (s->s_blocksize / 512) * sysv_nblocks(s, stat->size); + stat->blksize = s->s_blocksize; + return 0; +} + +static int sysv_writepage(struct page *page, struct writeback_control *wbc) +{ + return block_write_full_page(page,get_block,wbc); +} + +static int sysv_readpage(struct file *file, struct page *page) +{ + return block_read_full_page(page,get_block); +} + +int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len) +{ + return __block_write_begin(page, pos, len, get_block); +} + +static int sysv_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + int ret; + + ret = block_write_begin(mapping, pos, len, flags, pagep, get_block); + if (unlikely(ret)) { + loff_t isize = mapping->host->i_size; + if (pos + len > isize) + vmtruncate(mapping->host, isize); + } + + return ret; +} + +static sector_t sysv_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping,block,get_block); +} + +const struct address_space_operations sysv_aops = { + .readpage = sysv_readpage, + .writepage = sysv_writepage, + .write_begin = sysv_write_begin, + .write_end = generic_write_end, + .bmap = sysv_bmap +}; diff --git a/fs/sysv/namei.c b/fs/sysv/namei.c new file mode 100644 index 00000000..e474fbcf --- /dev/null +++ b/fs/sysv/namei.c @@ -0,0 +1,301 @@ +/* + * linux/fs/sysv/namei.c + * + * minix/namei.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * coh/namei.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/namei.c + * Copyright (C) 1993 Bruno Haible + * Copyright (C) 1997, 1998 Krzysztof G. Baranowski + */ + +#include <linux/pagemap.h> +#include "sysv.h" + +static int add_nondir(struct dentry *dentry, struct inode *inode) +{ + int err = sysv_add_link(dentry, inode); + if (!err) { + d_instantiate(dentry, inode); + return 0; + } + inode_dec_link_count(inode); + iput(inode); + return err; +} + +static int sysv_hash(const struct dentry *dentry, const struct inode *inode, + struct qstr *qstr) +{ + /* Truncate the name in place, avoids having to define a compare + function. */ + if (qstr->len > SYSV_NAMELEN) { + qstr->len = SYSV_NAMELEN; + qstr->hash = full_name_hash(qstr->name, qstr->len); + } + return 0; +} + +const struct dentry_operations sysv_dentry_operations = { + .d_hash = sysv_hash, +}; + +static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd) +{ + struct inode * inode = NULL; + ino_t ino; + + if (dentry->d_name.len > SYSV_NAMELEN) + return ERR_PTR(-ENAMETOOLONG); + ino = sysv_inode_by_name(dentry); + + if (ino) { + inode = sysv_iget(dir->i_sb, ino); + if (IS_ERR(inode)) + return ERR_CAST(inode); + } + d_add(dentry, inode); + return NULL; +} + +static int sysv_mknod(struct inode * dir, struct dentry * dentry, int mode, dev_t rdev) +{ + struct inode * inode; + int err; + + if (!old_valid_dev(rdev)) + return -EINVAL; + + inode = sysv_new_inode(dir, mode); + err = PTR_ERR(inode); + + if (!IS_ERR(inode)) { + sysv_set_inode(inode, rdev); + mark_inode_dirty(inode); + err = add_nondir(dentry, inode); + } + return err; +} + +static int sysv_create(struct inode * dir, struct dentry * dentry, int mode, struct nameidata *nd) +{ + return sysv_mknod(dir, dentry, mode, 0); +} + +static int sysv_symlink(struct inode * dir, struct dentry * dentry, + const char * symname) +{ + int err = -ENAMETOOLONG; + int l = strlen(symname)+1; + struct inode * inode; + + if (l > dir->i_sb->s_blocksize) + goto out; + + inode = sysv_new_inode(dir, S_IFLNK|0777); + err = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out; + + sysv_set_inode(inode, 0); + err = page_symlink(inode, symname, l); + if (err) + goto out_fail; + + mark_inode_dirty(inode); + err = add_nondir(dentry, inode); +out: + return err; + +out_fail: + inode_dec_link_count(inode); + iput(inode); + goto out; +} + +static int sysv_link(struct dentry * old_dentry, struct inode * dir, + struct dentry * dentry) +{ + struct inode *inode = old_dentry->d_inode; + + if (inode->i_nlink >= SYSV_SB(inode->i_sb)->s_link_max) + return -EMLINK; + + inode->i_ctime = CURRENT_TIME_SEC; + inode_inc_link_count(inode); + ihold(inode); + + return add_nondir(dentry, inode); +} + +static int sysv_mkdir(struct inode * dir, struct dentry *dentry, int mode) +{ + struct inode * inode; + int err = -EMLINK; + + if (dir->i_nlink >= SYSV_SB(dir->i_sb)->s_link_max) + goto out; + inode_inc_link_count(dir); + + inode = sysv_new_inode(dir, S_IFDIR|mode); + err = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out_dir; + + sysv_set_inode(inode, 0); + + inode_inc_link_count(inode); + + err = sysv_make_empty(inode, dir); + if (err) + goto out_fail; + + err = sysv_add_link(dentry, inode); + if (err) + goto out_fail; + + d_instantiate(dentry, inode); +out: + return err; + +out_fail: + inode_dec_link_count(inode); + inode_dec_link_count(inode); + iput(inode); +out_dir: + inode_dec_link_count(dir); + goto out; +} + +static int sysv_unlink(struct inode * dir, struct dentry * dentry) +{ + struct inode * inode = dentry->d_inode; + struct page * page; + struct sysv_dir_entry * de; + int err = -ENOENT; + + de = sysv_find_entry(dentry, &page); + if (!de) + goto out; + + err = sysv_delete_entry (de, page); + if (err) + goto out; + + inode->i_ctime = dir->i_ctime; + inode_dec_link_count(inode); +out: + return err; +} + +static int sysv_rmdir(struct inode * dir, struct dentry * dentry) +{ + struct inode *inode = dentry->d_inode; + int err = -ENOTEMPTY; + + if (sysv_empty_dir(inode)) { + err = sysv_unlink(dir, dentry); + if (!err) { + inode->i_size = 0; + inode_dec_link_count(inode); + inode_dec_link_count(dir); + } + } + return err; +} + +/* + * Anybody can rename anything with this: the permission checks are left to the + * higher-level routines. + */ +static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry, + struct inode * new_dir, struct dentry * new_dentry) +{ + struct inode * old_inode = old_dentry->d_inode; + struct inode * new_inode = new_dentry->d_inode; + struct page * dir_page = NULL; + struct sysv_dir_entry * dir_de = NULL; + struct page * old_page; + struct sysv_dir_entry * old_de; + int err = -ENOENT; + + old_de = sysv_find_entry(old_dentry, &old_page); + if (!old_de) + goto out; + + if (S_ISDIR(old_inode->i_mode)) { + err = -EIO; + dir_de = sysv_dotdot(old_inode, &dir_page); + if (!dir_de) + goto out_old; + } + + if (new_inode) { + struct page * new_page; + struct sysv_dir_entry * new_de; + + err = -ENOTEMPTY; + if (dir_de && !sysv_empty_dir(new_inode)) + goto out_dir; + + err = -ENOENT; + new_de = sysv_find_entry(new_dentry, &new_page); + if (!new_de) + goto out_dir; + sysv_set_link(new_de, new_page, old_inode); + new_inode->i_ctime = CURRENT_TIME_SEC; + if (dir_de) + drop_nlink(new_inode); + inode_dec_link_count(new_inode); + } else { + if (dir_de) { + err = -EMLINK; + if (new_dir->i_nlink >= SYSV_SB(new_dir->i_sb)->s_link_max) + goto out_dir; + } + err = sysv_add_link(new_dentry, old_inode); + if (err) + goto out_dir; + if (dir_de) + inode_inc_link_count(new_dir); + } + + sysv_delete_entry(old_de, old_page); + mark_inode_dirty(old_inode); + + if (dir_de) { + sysv_set_link(dir_de, dir_page, new_dir); + inode_dec_link_count(old_dir); + } + return 0; + +out_dir: + if (dir_de) { + kunmap(dir_page); + page_cache_release(dir_page); + } +out_old: + kunmap(old_page); + page_cache_release(old_page); +out: + return err; +} + +/* + * directories can handle most operations... + */ +const struct inode_operations sysv_dir_inode_operations = { + .create = sysv_create, + .lookup = sysv_lookup, + .link = sysv_link, + .unlink = sysv_unlink, + .symlink = sysv_symlink, + .mkdir = sysv_mkdir, + .rmdir = sysv_rmdir, + .mknod = sysv_mknod, + .rename = sysv_rename, + .getattr = sysv_getattr, +}; diff --git a/fs/sysv/super.c b/fs/sysv/super.c new file mode 100644 index 00000000..f60c1969 --- /dev/null +++ b/fs/sysv/super.c @@ -0,0 +1,590 @@ +/* + * linux/fs/sysv/inode.c + * + * minix/inode.c + * Copyright (C) 1991, 1992 Linus Torvalds + * + * xenix/inode.c + * Copyright (C) 1992 Doug Evans + * + * coh/inode.c + * Copyright (C) 1993 Pascal Haible, Bruno Haible + * + * sysv/inode.c + * Copyright (C) 1993 Paul B. Monday + * + * sysv/inode.c + * Copyright (C) 1993 Bruno Haible + * Copyright (C) 1997, 1998 Krzysztof G. Baranowski + * + * This file contains code for read/parsing the superblock. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/buffer_head.h> +#include "sysv.h" + +/* + * The following functions try to recognize specific filesystems. + * + * We recognize: + * - Xenix FS by its magic number. + * - SystemV FS by its magic number. + * - Coherent FS by its funny fname/fpack field. + * - SCO AFS by s_nfree == 0xffff + * - V7 FS has no distinguishing features. + * + * We discriminate among SystemV4 and SystemV2 FS by the assumption that + * the time stamp is not < 01-01-1980. + */ + +enum { + JAN_1_1980 = (10*365 + 2) * 24 * 60 * 60 +}; + +static void detected_xenix(struct sysv_sb_info *sbi) +{ + struct buffer_head *bh1 = sbi->s_bh1; + struct buffer_head *bh2 = sbi->s_bh2; + struct xenix_super_block * sbd1; + struct xenix_super_block * sbd2; + + if (bh1 != bh2) + sbd1 = sbd2 = (struct xenix_super_block *) bh1->b_data; + else { + /* block size = 512, so bh1 != bh2 */ + sbd1 = (struct xenix_super_block *) bh1->b_data; + sbd2 = (struct xenix_super_block *) (bh2->b_data - 512); + } + + sbi->s_link_max = XENIX_LINK_MAX; + sbi->s_fic_size = XENIX_NICINOD; + sbi->s_flc_size = XENIX_NICFREE; + sbi->s_sbd1 = (char *)sbd1; + sbi->s_sbd2 = (char *)sbd2; + sbi->s_sb_fic_count = &sbd1->s_ninode; + sbi->s_sb_fic_inodes = &sbd1->s_inode[0]; + sbi->s_sb_total_free_inodes = &sbd2->s_tinode; + sbi->s_bcache_count = &sbd1->s_nfree; + sbi->s_bcache = &sbd1->s_free[0]; + sbi->s_free_blocks = &sbd2->s_tfree; + sbi->s_sb_time = &sbd2->s_time; + sbi->s_firstdatazone = fs16_to_cpu(sbi, sbd1->s_isize); + sbi->s_nzones = fs32_to_cpu(sbi, sbd1->s_fsize); +} + +static void detected_sysv4(struct sysv_sb_info *sbi) +{ + struct sysv4_super_block * sbd; + struct buffer_head *bh1 = sbi->s_bh1; + struct buffer_head *bh2 = sbi->s_bh2; + + if (bh1 == bh2) + sbd = (struct sysv4_super_block *) (bh1->b_data + BLOCK_SIZE/2); + else + sbd = (struct sysv4_super_block *) bh2->b_data; + + sbi->s_link_max = SYSV_LINK_MAX; + sbi->s_fic_size = SYSV_NICINOD; + sbi->s_flc_size = SYSV_NICFREE; + sbi->s_sbd1 = (char *)sbd; + sbi->s_sbd2 = (char *)sbd; + sbi->s_sb_fic_count = &sbd->s_ninode; + sbi->s_sb_fic_inodes = &sbd->s_inode[0]; + sbi->s_sb_total_free_inodes = &sbd->s_tinode; + sbi->s_bcache_count = &sbd->s_nfree; + sbi->s_bcache = &sbd->s_free[0]; + sbi->s_free_blocks = &sbd->s_tfree; + sbi->s_sb_time = &sbd->s_time; + sbi->s_sb_state = &sbd->s_state; + sbi->s_firstdatazone = fs16_to_cpu(sbi, sbd->s_isize); + sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); +} + +static void detected_sysv2(struct sysv_sb_info *sbi) +{ + struct sysv2_super_block *sbd; + struct buffer_head *bh1 = sbi->s_bh1; + struct buffer_head *bh2 = sbi->s_bh2; + + if (bh1 == bh2) + sbd = (struct sysv2_super_block *) (bh1->b_data + BLOCK_SIZE/2); + else + sbd = (struct sysv2_super_block *) bh2->b_data; + + sbi->s_link_max = SYSV_LINK_MAX; + sbi->s_fic_size = SYSV_NICINOD; + sbi->s_flc_size = SYSV_NICFREE; + sbi->s_sbd1 = (char *)sbd; + sbi->s_sbd2 = (char *)sbd; + sbi->s_sb_fic_count = &sbd->s_ninode; + sbi->s_sb_fic_inodes = &sbd->s_inode[0]; + sbi->s_sb_total_free_inodes = &sbd->s_tinode; + sbi->s_bcache_count = &sbd->s_nfree; + sbi->s_bcache = &sbd->s_free[0]; + sbi->s_free_blocks = &sbd->s_tfree; + sbi->s_sb_time = &sbd->s_time; + sbi->s_sb_state = &sbd->s_state; + sbi->s_firstdatazone = fs16_to_cpu(sbi, sbd->s_isize); + sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); +} + +static void detected_coherent(struct sysv_sb_info *sbi) +{ + struct coh_super_block * sbd; + struct buffer_head *bh1 = sbi->s_bh1; + + sbd = (struct coh_super_block *) bh1->b_data; + + sbi->s_link_max = COH_LINK_MAX; + sbi->s_fic_size = COH_NICINOD; + sbi->s_flc_size = COH_NICFREE; + sbi->s_sbd1 = (char *)sbd; + sbi->s_sbd2 = (char *)sbd; + sbi->s_sb_fic_count = &sbd->s_ninode; + sbi->s_sb_fic_inodes = &sbd->s_inode[0]; + sbi->s_sb_total_free_inodes = &sbd->s_tinode; + sbi->s_bcache_count = &sbd->s_nfree; + sbi->s_bcache = &sbd->s_free[0]; + sbi->s_free_blocks = &sbd->s_tfree; + sbi->s_sb_time = &sbd->s_time; + sbi->s_firstdatazone = fs16_to_cpu(sbi, sbd->s_isize); + sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); +} + +static void detected_v7(struct sysv_sb_info *sbi) +{ + struct buffer_head *bh2 = sbi->s_bh2; + struct v7_super_block *sbd = (struct v7_super_block *)bh2->b_data; + + sbi->s_link_max = V7_LINK_MAX; + sbi->s_fic_size = V7_NICINOD; + sbi->s_flc_size = V7_NICFREE; + sbi->s_sbd1 = (char *)sbd; + sbi->s_sbd2 = (char *)sbd; + sbi->s_sb_fic_count = &sbd->s_ninode; + sbi->s_sb_fic_inodes = &sbd->s_inode[0]; + sbi->s_sb_total_free_inodes = &sbd->s_tinode; + sbi->s_bcache_count = &sbd->s_nfree; + sbi->s_bcache = &sbd->s_free[0]; + sbi->s_free_blocks = &sbd->s_tfree; + sbi->s_sb_time = &sbd->s_time; + sbi->s_firstdatazone = fs16_to_cpu(sbi, sbd->s_isize); + sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); +} + +static int detect_xenix(struct sysv_sb_info *sbi, struct buffer_head *bh) +{ + struct xenix_super_block *sbd = (struct xenix_super_block *)bh->b_data; + if (*(__le32 *)&sbd->s_magic == cpu_to_le32(0x2b5544)) + sbi->s_bytesex = BYTESEX_LE; + else if (*(__be32 *)&sbd->s_magic == cpu_to_be32(0x2b5544)) + sbi->s_bytesex = BYTESEX_BE; + else + return 0; + switch (fs32_to_cpu(sbi, sbd->s_type)) { + case 1: + sbi->s_type = FSTYPE_XENIX; + return 1; + case 2: + sbi->s_type = FSTYPE_XENIX; + return 2; + default: + return 0; + } +} + +static int detect_sysv(struct sysv_sb_info *sbi, struct buffer_head *bh) +{ + struct super_block *sb = sbi->s_sb; + /* All relevant fields are at the same offsets in R2 and R4 */ + struct sysv4_super_block * sbd; + u32 type; + + sbd = (struct sysv4_super_block *) (bh->b_data + BLOCK_SIZE/2); + if (*(__le32 *)&sbd->s_magic == cpu_to_le32(0xfd187e20)) + sbi->s_bytesex = BYTESEX_LE; + else if (*(__be32 *)&sbd->s_magic == cpu_to_be32(0xfd187e20)) + sbi->s_bytesex = BYTESEX_BE; + else + return 0; + + type = fs32_to_cpu(sbi, sbd->s_type); + + if (fs16_to_cpu(sbi, sbd->s_nfree) == 0xffff) { + sbi->s_type = FSTYPE_AFS; + sbi->s_forced_ro = 1; + if (!(sb->s_flags & MS_RDONLY)) { + printk("SysV FS: SCO EAFS on %s detected, " + "forcing read-only mode.\n", + sb->s_id); + } + return type; + } + + if (fs32_to_cpu(sbi, sbd->s_time) < JAN_1_1980) { + /* this is likely to happen on SystemV2 FS */ + if (type > 3 || type < 1) + return 0; + sbi->s_type = FSTYPE_SYSV2; + return type; + } + if ((type > 3 || type < 1) && (type > 0x30 || type < 0x10)) + return 0; + + /* On Interactive Unix (ISC) Version 4.0/3.x s_type field = 0x10, + 0x20 or 0x30 indicates that symbolic links and the 14-character + filename limit is gone. Due to lack of information about this + feature read-only mode seems to be a reasonable approach... -KGB */ + + if (type >= 0x10) { + printk("SysV FS: can't handle long file names on %s, " + "forcing read-only mode.\n", sb->s_id); + sbi->s_forced_ro = 1; + } + + sbi->s_type = FSTYPE_SYSV4; + return type >= 0x10 ? type >> 4 : type; +} + +static int detect_coherent(struct sysv_sb_info *sbi, struct buffer_head *bh) +{ + struct coh_super_block * sbd; + + sbd = (struct coh_super_block *) (bh->b_data + BLOCK_SIZE/2); + if ((memcmp(sbd->s_fname,"noname",6) && memcmp(sbd->s_fname,"xxxxx ",6)) + || (memcmp(sbd->s_fpack,"nopack",6) && memcmp(sbd->s_fpack,"xxxxx\n",6))) + return 0; + sbi->s_bytesex = BYTESEX_PDP; + sbi->s_type = FSTYPE_COH; + return 1; +} + +static int detect_sysv_odd(struct sysv_sb_info *sbi, struct buffer_head *bh) +{ + int size = detect_sysv(sbi, bh); + + return size>2 ? 0 : size; +} + +static struct { + int block; + int (*test)(struct sysv_sb_info *, struct buffer_head *); +} flavours[] = { + {1, detect_xenix}, + {0, detect_sysv}, + {0, detect_coherent}, + {9, detect_sysv_odd}, + {15,detect_sysv_odd}, + {18,detect_sysv}, +}; + +static char *flavour_names[] = { + [FSTYPE_XENIX] = "Xenix", + [FSTYPE_SYSV4] = "SystemV", + [FSTYPE_SYSV2] = "SystemV Release 2", + [FSTYPE_COH] = "Coherent", + [FSTYPE_V7] = "V7", + [FSTYPE_AFS] = "AFS", +}; + +static void (*flavour_setup[])(struct sysv_sb_info *) = { + [FSTYPE_XENIX] = detected_xenix, + [FSTYPE_SYSV4] = detected_sysv4, + [FSTYPE_SYSV2] = detected_sysv2, + [FSTYPE_COH] = detected_coherent, + [FSTYPE_V7] = detected_v7, + [FSTYPE_AFS] = detected_sysv4, +}; + +static int complete_read_super(struct super_block *sb, int silent, int size) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + struct inode *root_inode; + char *found = flavour_names[sbi->s_type]; + u_char n_bits = size+8; + int bsize = 1 << n_bits; + int bsize_4 = bsize >> 2; + + sbi->s_firstinodezone = 2; + + flavour_setup[sbi->s_type](sbi); + + sbi->s_truncate = 1; + sbi->s_ndatazones = sbi->s_nzones - sbi->s_firstdatazone; + sbi->s_inodes_per_block = bsize >> 6; + sbi->s_inodes_per_block_1 = (bsize >> 6)-1; + sbi->s_inodes_per_block_bits = n_bits-6; + sbi->s_ind_per_block = bsize_4; + sbi->s_ind_per_block_2 = bsize_4*bsize_4; + sbi->s_toobig_block = 10 + bsize_4 * (1 + bsize_4 * (1 + bsize_4)); + sbi->s_ind_per_block_bits = n_bits-2; + + sbi->s_ninodes = (sbi->s_firstdatazone - sbi->s_firstinodezone) + << sbi->s_inodes_per_block_bits; + + if (!silent) + printk("VFS: Found a %s FS (block size = %ld) on device %s\n", + found, sb->s_blocksize, sb->s_id); + + sb->s_magic = SYSV_MAGIC_BASE + sbi->s_type; + /* set up enough so that it can read an inode */ + sb->s_op = &sysv_sops; + if (sbi->s_forced_ro) + sb->s_flags |= MS_RDONLY; + if (sbi->s_truncate) + sb->s_d_op = &sysv_dentry_operations; + root_inode = sysv_iget(sb, SYSV_ROOT_INO); + if (IS_ERR(root_inode)) { + printk("SysV FS: get root inode failed\n"); + return 0; + } + sb->s_root = d_alloc_root(root_inode); + if (!sb->s_root) { + iput(root_inode); + printk("SysV FS: get root dentry failed\n"); + return 0; + } + return 1; +} + +static int sysv_fill_super(struct super_block *sb, void *data, int silent) +{ + struct buffer_head *bh1, *bh = NULL; + struct sysv_sb_info *sbi; + unsigned long blocknr; + int size = 0, i; + + BUILD_BUG_ON(1024 != sizeof (struct xenix_super_block)); + BUILD_BUG_ON(512 != sizeof (struct sysv4_super_block)); + BUILD_BUG_ON(512 != sizeof (struct sysv2_super_block)); + BUILD_BUG_ON(500 != sizeof (struct coh_super_block)); + BUILD_BUG_ON(64 != sizeof (struct sysv_inode)); + + sbi = kzalloc(sizeof(struct sysv_sb_info), GFP_KERNEL); + if (!sbi) + return -ENOMEM; + + sbi->s_sb = sb; + sbi->s_block_base = 0; + sb->s_fs_info = sbi; + + sb_set_blocksize(sb, BLOCK_SIZE); + + for (i = 0; i < ARRAY_SIZE(flavours) && !size; i++) { + brelse(bh); + bh = sb_bread(sb, flavours[i].block); + if (!bh) + continue; + size = flavours[i].test(SYSV_SB(sb), bh); + } + + if (!size) + goto Eunknown; + + switch (size) { + case 1: + blocknr = bh->b_blocknr << 1; + brelse(bh); + sb_set_blocksize(sb, 512); + bh1 = sb_bread(sb, blocknr); + bh = sb_bread(sb, blocknr + 1); + break; + case 2: + bh1 = bh; + break; + case 3: + blocknr = bh->b_blocknr >> 1; + brelse(bh); + sb_set_blocksize(sb, 2048); + bh1 = bh = sb_bread(sb, blocknr); + break; + default: + goto Ebadsize; + } + + if (bh && bh1) { + sbi->s_bh1 = bh1; + sbi->s_bh2 = bh; + if (complete_read_super(sb, silent, size)) + return 0; + } + + brelse(bh1); + brelse(bh); + sb_set_blocksize(sb, BLOCK_SIZE); + printk("oldfs: cannot read superblock\n"); +failed: + kfree(sbi); + return -EINVAL; + +Eunknown: + brelse(bh); + if (!silent) + printk("VFS: unable to find oldfs superblock on device %s\n", + sb->s_id); + goto failed; +Ebadsize: + brelse(bh); + if (!silent) + printk("VFS: oldfs: unsupported block size (%dKb)\n", + 1<<(size-2)); + goto failed; +} + +static int v7_sanity_check(struct super_block *sb, struct buffer_head *bh) +{ + struct v7_super_block *v7sb; + struct sysv_inode *v7i; + struct buffer_head *bh2; + struct sysv_sb_info *sbi; + + sbi = sb->s_fs_info; + + /* plausibility check on superblock */ + v7sb = (struct v7_super_block *) bh->b_data; + if (fs16_to_cpu(sbi, v7sb->s_nfree) > V7_NICFREE || + fs16_to_cpu(sbi, v7sb->s_ninode) > V7_NICINOD || + fs32_to_cpu(sbi, v7sb->s_fsize) > V7_MAXSIZE) + return 0; + + /* plausibility check on root inode: it is a directory, + with a nonzero size that is a multiple of 16 */ + bh2 = sb_bread(sb, 2); + if (bh2 == NULL) + return 0; + + v7i = (struct sysv_inode *)(bh2->b_data + 64); + if ((fs16_to_cpu(sbi, v7i->i_mode) & ~0777) != S_IFDIR || + (fs32_to_cpu(sbi, v7i->i_size) == 0) || + (fs32_to_cpu(sbi, v7i->i_size) & 017) || + (fs32_to_cpu(sbi, v7i->i_size) > V7_NFILES * + sizeof(struct sysv_dir_entry))) { + brelse(bh2); + return 0; + } + + brelse(bh2); + return 1; +} + +static int v7_fill_super(struct super_block *sb, void *data, int silent) +{ + struct sysv_sb_info *sbi; + struct buffer_head *bh; + + if (440 != sizeof (struct v7_super_block)) + panic("V7 FS: bad super-block size"); + if (64 != sizeof (struct sysv_inode)) + panic("sysv fs: bad i-node size"); + + sbi = kzalloc(sizeof(struct sysv_sb_info), GFP_KERNEL); + if (!sbi) + return -ENOMEM; + + sbi->s_sb = sb; + sbi->s_block_base = 0; + sbi->s_type = FSTYPE_V7; + sb->s_fs_info = sbi; + + sb_set_blocksize(sb, 512); + + if ((bh = sb_bread(sb, 1)) == NULL) { + if (!silent) + printk("VFS: unable to read V7 FS superblock on " + "device %s.\n", sb->s_id); + goto failed; + } + + /* Try PDP-11 UNIX */ + sbi->s_bytesex = BYTESEX_PDP; + if (v7_sanity_check(sb, bh)) + goto detected; + + /* Try PC/IX, v7/x86 */ + sbi->s_bytesex = BYTESEX_LE; + if (v7_sanity_check(sb, bh)) + goto detected; + + goto failed; + +detected: + sbi->s_bh1 = bh; + sbi->s_bh2 = bh; + if (complete_read_super(sb, silent, 1)) + return 0; + +failed: + printk(KERN_ERR "VFS: could not find a valid V7 on %s.\n", + sb->s_id); + brelse(bh); + kfree(sbi); + return -EINVAL; +} + +/* Every kernel module contains stuff like this. */ + +static struct dentry *sysv_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, sysv_fill_super); +} + +static struct dentry *v7_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, v7_fill_super); +} + +static struct file_system_type sysv_fs_type = { + .owner = THIS_MODULE, + .name = "sysv", + .mount = sysv_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; + +static struct file_system_type v7_fs_type = { + .owner = THIS_MODULE, + .name = "v7", + .mount = v7_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; + +static int __init init_sysv_fs(void) +{ + int error; + + error = sysv_init_icache(); + if (error) + goto out; + error = register_filesystem(&sysv_fs_type); + if (error) + goto destroy_icache; + error = register_filesystem(&v7_fs_type); + if (error) + goto unregister; + return 0; + +unregister: + unregister_filesystem(&sysv_fs_type); +destroy_icache: + sysv_destroy_icache(); +out: + return error; +} + +static void __exit exit_sysv_fs(void) +{ + unregister_filesystem(&sysv_fs_type); + unregister_filesystem(&v7_fs_type); + sysv_destroy_icache(); +} + +module_init(init_sysv_fs) +module_exit(exit_sysv_fs) +MODULE_ALIAS("v7"); +MODULE_LICENSE("GPL"); diff --git a/fs/sysv/symlink.c b/fs/sysv/symlink.c new file mode 100644 index 00000000..00d2f8a4 --- /dev/null +++ b/fs/sysv/symlink.c @@ -0,0 +1,20 @@ +/* + * linux/fs/sysv/symlink.c + * + * Handling of System V filesystem fast symlinks extensions. + * Aug 2001, Christoph Hellwig (hch@infradead.org) + */ + +#include "sysv.h" +#include <linux/namei.h> + +static void *sysv_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + nd_set_link(nd, (char *)SYSV_I(dentry->d_inode)->i_data); + return NULL; +} + +const struct inode_operations sysv_fast_symlink_inode_operations = { + .readlink = generic_readlink, + .follow_link = sysv_follow_link, +}; diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h new file mode 100644 index 00000000..bb55cdb3 --- /dev/null +++ b/fs/sysv/sysv.h @@ -0,0 +1,248 @@ +#ifndef _SYSV_H +#define _SYSV_H + +#include <linux/buffer_head.h> + +typedef __u16 __bitwise __fs16; +typedef __u32 __bitwise __fs32; + +#include <linux/sysv_fs.h> + +/* + * SystemV/V7/Coherent super-block data in memory + * + * The SystemV/V7/Coherent superblock contains dynamic data (it gets modified + * while the system is running). This is in contrast to the Minix and Berkeley + * filesystems (where the superblock is never modified). This affects the + * sync() operation: we must keep the superblock in a disk buffer and use this + * one as our "working copy". + */ + +struct sysv_sb_info { + struct super_block *s_sb; /* VFS superblock */ + int s_type; /* file system type: FSTYPE_{XENIX|SYSV|COH} */ + char s_bytesex; /* bytesex (le/be/pdp) */ + char s_truncate; /* if 1: names > SYSV_NAMELEN chars are truncated */ + /* if 0: they are disallowed (ENAMETOOLONG) */ + nlink_t s_link_max; /* max number of hard links to a file */ + unsigned int s_inodes_per_block; /* number of inodes per block */ + unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */ + unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */ + unsigned int s_ind_per_block; /* number of indirections per block */ + unsigned int s_ind_per_block_bits; /* log2(ind_per_block) */ + unsigned int s_ind_per_block_2; /* ind_per_block ^ 2 */ + unsigned int s_toobig_block; /* 10 + ipb + ipb^2 + ipb^3 */ + unsigned int s_block_base; /* physical block number of block 0 */ + unsigned short s_fic_size; /* free inode cache size, NICINOD */ + unsigned short s_flc_size; /* free block list chunk size, NICFREE */ + /* The superblock is kept in one or two disk buffers: */ + struct buffer_head *s_bh1; + struct buffer_head *s_bh2; + /* These are pointers into the disk buffer, to compensate for + different superblock layout. */ + char * s_sbd1; /* entire superblock data, for part 1 */ + char * s_sbd2; /* entire superblock data, for part 2 */ + __fs16 *s_sb_fic_count; /* pointer to s_sbd->s_ninode */ + sysv_ino_t *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */ + __fs16 *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */ + __fs16 *s_bcache_count; /* pointer to s_sbd->s_nfree */ + sysv_zone_t *s_bcache; /* pointer to s_sbd->s_free */ + __fs32 *s_free_blocks; /* pointer to s_sbd->s_tfree */ + __fs32 *s_sb_time; /* pointer to s_sbd->s_time */ + __fs32 *s_sb_state; /* pointer to s_sbd->s_state, only FSTYPE_SYSV */ + /* We keep those superblock entities that don't change here; + this saves us an indirection and perhaps a conversion. */ + u32 s_firstinodezone; /* index of first inode zone */ + u32 s_firstdatazone; /* same as s_sbd->s_isize */ + u32 s_ninodes; /* total number of inodes */ + u32 s_ndatazones; /* total number of data zones */ + u32 s_nzones; /* same as s_sbd->s_fsize */ + u16 s_namelen; /* max length of dir entry */ + int s_forced_ro; +}; + +/* + * SystemV/V7/Coherent FS inode data in memory + */ +struct sysv_inode_info { + __fs32 i_data[13]; + u32 i_dir_start_lookup; + struct inode vfs_inode; +}; + + +static inline struct sysv_inode_info *SYSV_I(struct inode *inode) +{ + return list_entry(inode, struct sysv_inode_info, vfs_inode); +} + +static inline struct sysv_sb_info *SYSV_SB(struct super_block *sb) +{ + return sb->s_fs_info; +} + + +/* identify the FS in memory */ +enum { + FSTYPE_NONE = 0, + FSTYPE_XENIX, + FSTYPE_SYSV4, + FSTYPE_SYSV2, + FSTYPE_COH, + FSTYPE_V7, + FSTYPE_AFS, + FSTYPE_END, +}; + +#define SYSV_MAGIC_BASE 0x012FF7B3 + +#define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX) +#define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4) +#define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2) +#define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH) + + +/* Admissible values for i_nlink: 0.._LINK_MAX */ +enum { + XENIX_LINK_MAX = 126, /* ?? */ + SYSV_LINK_MAX = 126, /* 127? 251? */ + V7_LINK_MAX = 126, /* ?? */ + COH_LINK_MAX = 10000, +}; + + +static inline void dirty_sb(struct super_block *sb) +{ + struct sysv_sb_info *sbi = SYSV_SB(sb); + + mark_buffer_dirty(sbi->s_bh1); + if (sbi->s_bh1 != sbi->s_bh2) + mark_buffer_dirty(sbi->s_bh2); + sb->s_dirt = 1; +} + + +/* ialloc.c */ +extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned, + struct buffer_head **); +extern struct inode * sysv_new_inode(const struct inode *, mode_t); +extern void sysv_free_inode(struct inode *); +extern unsigned long sysv_count_free_inodes(struct super_block *); + +/* balloc.c */ +extern sysv_zone_t sysv_new_block(struct super_block *); +extern void sysv_free_block(struct super_block *, sysv_zone_t); +extern unsigned long sysv_count_free_blocks(struct super_block *); + +/* itree.c */ +extern void sysv_truncate(struct inode *); +extern int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len); + +/* inode.c */ +extern struct inode *sysv_iget(struct super_block *, unsigned int); +extern int sysv_write_inode(struct inode *, struct writeback_control *wbc); +extern int sysv_sync_inode(struct inode *); +extern void sysv_set_inode(struct inode *, dev_t); +extern int sysv_getattr(struct vfsmount *, struct dentry *, struct kstat *); +extern int sysv_init_icache(void); +extern void sysv_destroy_icache(void); + + +/* dir.c */ +extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **); +extern int sysv_add_link(struct dentry *, struct inode *); +extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *); +extern int sysv_make_empty(struct inode *, struct inode *); +extern int sysv_empty_dir(struct inode *); +extern void sysv_set_link(struct sysv_dir_entry *, struct page *, + struct inode *); +extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **); +extern ino_t sysv_inode_by_name(struct dentry *); + + +extern const struct inode_operations sysv_file_inode_operations; +extern const struct inode_operations sysv_dir_inode_operations; +extern const struct inode_operations sysv_fast_symlink_inode_operations; +extern const struct file_operations sysv_file_operations; +extern const struct file_operations sysv_dir_operations; +extern const struct address_space_operations sysv_aops; +extern const struct super_operations sysv_sops; +extern const struct dentry_operations sysv_dentry_operations; + + +enum { + BYTESEX_LE, + BYTESEX_PDP, + BYTESEX_BE, +}; + +static inline u32 PDP_swab(u32 x) +{ +#ifdef __LITTLE_ENDIAN + return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16); +#else +#ifdef __BIG_ENDIAN + return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8); +#else +#error BYTESEX +#endif +#endif +} + +static inline __u32 fs32_to_cpu(struct sysv_sb_info *sbi, __fs32 n) +{ + if (sbi->s_bytesex == BYTESEX_PDP) + return PDP_swab((__force __u32)n); + else if (sbi->s_bytesex == BYTESEX_LE) + return le32_to_cpu((__force __le32)n); + else + return be32_to_cpu((__force __be32)n); +} + +static inline __fs32 cpu_to_fs32(struct sysv_sb_info *sbi, __u32 n) +{ + if (sbi->s_bytesex == BYTESEX_PDP) + return (__force __fs32)PDP_swab(n); + else if (sbi->s_bytesex == BYTESEX_LE) + return (__force __fs32)cpu_to_le32(n); + else + return (__force __fs32)cpu_to_be32(n); +} + +static inline __fs32 fs32_add(struct sysv_sb_info *sbi, __fs32 *n, int d) +{ + if (sbi->s_bytesex == BYTESEX_PDP) + *(__u32*)n = PDP_swab(PDP_swab(*(__u32*)n)+d); + else if (sbi->s_bytesex == BYTESEX_LE) + le32_add_cpu((__le32 *)n, d); + else + be32_add_cpu((__be32 *)n, d); + return *n; +} + +static inline __u16 fs16_to_cpu(struct sysv_sb_info *sbi, __fs16 n) +{ + if (sbi->s_bytesex != BYTESEX_BE) + return le16_to_cpu((__force __le16)n); + else + return be16_to_cpu((__force __be16)n); +} + +static inline __fs16 cpu_to_fs16(struct sysv_sb_info *sbi, __u16 n) +{ + if (sbi->s_bytesex != BYTESEX_BE) + return (__force __fs16)cpu_to_le16(n); + else + return (__force __fs16)cpu_to_be16(n); +} + +static inline __fs16 fs16_add(struct sysv_sb_info *sbi, __fs16 *n, int d) +{ + if (sbi->s_bytesex != BYTESEX_BE) + le16_add_cpu((__le16 *)n, d); + else + be16_add_cpu((__be16 *)n, d); + return *n; +} + +#endif /* _SYSV_H */ |