v4.19.13 snapshot.
diff --git a/fs/sysv/Kconfig b/fs/sysv/Kconfig
new file mode 100644
index 0000000..33aeb4b
--- /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 0000000..7a75e70
--- /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
diff --git a/fs/sysv/balloc.c b/fs/sysv/balloc.c
new file mode 100644
index 0000000..0e69dbd
--- /dev/null
+++ b/fs/sysv/balloc.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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;
+ }
+
+ mutex_lock(&sbi->s_lock);
+ count = fs16_to_cpu(sbi, *sbi->s_bcache_count);
+
+ if (count > sbi->s_flc_size) {
+ printk("sysv_free_block: flc_count > flc_size\n");
+ mutex_unlock(&sbi->s_lock);
+ 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");
+ mutex_unlock(&sbi->s_lock);
+ 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);
+ mutex_unlock(&sbi->s_lock);
+}
+
+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;
+
+ mutex_lock(&sbi->s_lock);
+ 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);
+ mutex_unlock(&sbi->s_lock);
+ return nr;
+
+Enospc:
+ mutex_unlock(&sbi->s_lock);
+ 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;
+
+ mutex_lock(&sbi->s_lock);
+ 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:
+ mutex_unlock(&sbi->s_lock);
+ 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_rdonly(sb)) {
+ *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 0000000..88e38cd
--- /dev/null
+++ b/fs/sysv/dir.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 *, struct dir_context *);
+
+const struct file_operations sysv_dir_operations = {
+ .llseek = generic_file_llseek,
+ .read = generic_read_dir,
+ .iterate_shared = sysv_readdir,
+ .fsync = generic_file_fsync,
+};
+
+static inline void dir_put_page(struct page *page)
+{
+ kunmap(page);
+ put_page(page);
+}
+
+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);
+ 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 *file, struct dir_context *ctx)
+{
+ unsigned long pos = ctx->pos;
+ struct inode *inode = file_inode(file);
+ struct super_block *sb = inode->i_sb;
+ unsigned long npages = dir_pages(inode);
+ unsigned offset;
+ unsigned long n;
+
+ ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
+ if (pos >= inode->i_size)
+ return 0;
+
+ offset = pos & ~PAGE_MASK;
+ n = pos >> PAGE_SHIFT;
+
+ 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_SIZE - SYSV_DIRSIZE;
+ for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) {
+ char *name = de->name;
+
+ if (!de->inode)
+ continue;
+
+ if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
+ fs16_to_cpu(SYSV_SB(sb), de->inode),
+ DT_UNKNOWN)) {
+ dir_put_page(page);
+ return 0;
+ }
+ }
+ dir_put_page(page);
+ }
+ 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 = d_inode(dentry->d_parent);
+ 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_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 = d_inode(dentry->d_parent);
+ 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_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(dir);
+ 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(inode);
+ 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_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:
+ put_page(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_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(dir);
+ 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 0000000..45fc79a
--- /dev/null
+++ b/fs/sysv/file.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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_iter = generic_file_read_iter,
+ .write_iter = generic_file_write_iter,
+ .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 = d_inode(dentry);
+ int error;
+
+ error = setattr_prepare(dentry, attr);
+ if (error)
+ return error;
+
+ if ((attr->ia_valid & ATTR_SIZE) &&
+ attr->ia_size != i_size_read(inode)) {
+ error = inode_newsize_ok(inode, attr->ia_size);
+ if (error)
+ return error;
+ truncate_setsize(inode, attr->ia_size);
+ sysv_truncate(inode);
+ }
+
+ setattr_copy(inode, attr);
+ mark_inode_dirty(inode);
+ return 0;
+}
+
+const struct inode_operations sysv_file_inode_operations = {
+ .setattr = sysv_setattr,
+ .getattr = sysv_getattr,
+};
diff --git a/fs/sysv/ialloc.c b/fs/sysv/ialloc.c
new file mode 100644
index 0000000..6c98019
--- /dev/null
+++ b/fs/sysv/ialloc.c
@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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;
+ }
+ mutex_lock(&sbi->s_lock);
+ 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);
+ mutex_unlock(&sbi->s_lock);
+ brelse(bh);
+}
+
+struct inode * sysv_new_inode(const struct inode * dir, umode_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);
+
+ mutex_lock(&sbi->s_lock);
+ 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);
+ mutex_unlock(&sbi->s_lock);
+ 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(inode);
+ 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. */
+ mutex_unlock(&sbi->s_lock);
+ 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;
+
+ mutex_lock(&sbi->s_lock);
+
+ 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:
+ mutex_unlock(&sbi->s_lock);
+ return count;
+
+Einval:
+ printk("sysv_count_free_inodes: "
+ "free inode count was %d, correcting to %d\n",
+ sb_count, count);
+ if (!sb_rdonly(sb)) {
+ *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 0000000..273736f
--- /dev/null
+++ b/fs/sysv/inode.c
@@ -0,0 +1,364 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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);
+ u32 time = (u32)ktime_get_real_seconds(), old_time;
+
+ mutex_lock(&sbi->s_lock);
+
+ /*
+ * 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.
+ */
+ 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, 0x7c269d38u - old_time))
+ *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38u - time);
+ *sbi->s_sb_time = cpu_to_fs32(sbi, time);
+ mark_buffer_dirty(sbi->s_bh2);
+ }
+
+ mutex_unlock(&sbi->s_lock);
+
+ return 0;
+}
+
+static int sysv_remount(struct super_block *sb, int *flags, char *data)
+{
+ struct sysv_sb_info *sbi = SYSV_SB(sb);
+
+ sync_filesystem(sb);
+ if (sbi->s_forced_ro)
+ *flags |= SB_RDONLY;
+ return 0;
+}
+
+static void sysv_put_super(struct super_block *sb)
+{
+ struct sysv_sb_info *sbi = SYSV_SB(sb);
+
+ if (!sb_rdonly(sb)) {
+ /* 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 = {
+ .get_link = page_get_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)) {
+ inode->i_op = &sysv_symlink_inode_operations;
+ inode_nohighmem(inode);
+ inode->i_mapping->a_ops = &sysv_aops;
+ } 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);
+ i_uid_write(inode, (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid));
+ i_gid_write(inode, (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid));
+ set_nlink(inode, 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(i_uid_read(inode)));
+ raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(i_gid_read(inode)));
+ 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 err;
+}
+
+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_final(&inode->i_data);
+ if (!inode->i_nlink) {
+ inode->i_size = 0;
+ sysv_truncate(inode);
+ }
+ invalidate_inode_buffers(inode);
+ clear_inode(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);
+ 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,
+ .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|SLAB_ACCOUNT,
+ init_once);
+ if (!sysv_inode_cachep)
+ return -ENOMEM;
+ return 0;
+}
+
+void sysv_destroy_icache(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(sysv_inode_cachep);
+}
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c
new file mode 100644
index 0000000..bcb67b0
--- /dev/null
+++ b/fs/sysv/itree.c
@@ -0,0 +1,503 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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(inode);
+
+ /* 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(inode);
+ 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(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int flags)
+{
+ struct super_block *s = path->dentry->d_sb;
+ generic_fillattr(d_inode(path->dentry), 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 void sysv_write_failed(struct address_space *mapping, loff_t to)
+{
+ struct inode *inode = mapping->host;
+
+ if (to > inode->i_size) {
+ truncate_pagecache(inode, inode->i_size);
+ sysv_truncate(inode);
+ }
+}
+
+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))
+ sysv_write_failed(mapping, pos + len);
+
+ 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 0000000..4d5d204
--- /dev/null
+++ b/fs/sysv/namei.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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, 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(dentry, 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, unsigned int flags)
+{
+ 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);
+ return d_splice_alias(inode, dentry);
+}
+
+static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t 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, umode_t mode, bool excl)
+{
+ 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 = d_inode(old_dentry);
+
+ inode->i_ctime = current_time(inode);
+ inode_inc_link_count(inode);
+ ihold(inode);
+
+ return add_nondir(dentry, inode);
+}
+
+static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
+{
+ struct inode * inode;
+ int err;
+
+ 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 = d_inode(dentry);
+ 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 = d_inode(dentry);
+ 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,
+ unsigned int flags)
+{
+ struct inode * old_inode = d_inode(old_dentry);
+ struct inode * new_inode = d_inode(new_dentry);
+ 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;
+
+ if (flags & ~RENAME_NOREPLACE)
+ return -EINVAL;
+
+ 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(new_inode);
+ if (dir_de)
+ drop_nlink(new_inode);
+ inode_dec_link_count(new_inode);
+ } else {
+ 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);
+ put_page(dir_page);
+ }
+out_old:
+ kunmap(old_page);
+ put_page(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 0000000..89765dd
--- /dev/null
+++ b/fs/sysv/super.c
@@ -0,0 +1,593 @@
+/*
+ * 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, unsigned *max_links)
+{
+ 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);
+ }
+
+ *max_links = 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, unsigned *max_links)
+{
+ 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;
+
+ *max_links = 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, unsigned *max_links)
+{
+ 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;
+
+ *max_links = 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, unsigned *max_links)
+{
+ struct coh_super_block * sbd;
+ struct buffer_head *bh1 = sbi->s_bh1;
+
+ sbd = (struct coh_super_block *) bh1->b_data;
+
+ *max_links = 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, unsigned *max_links)
+{
+ struct buffer_head *bh2 = sbi->s_bh2;
+ struct v7_super_block *sbd = (struct v7_super_block *)bh2->b_data;
+
+ *max_links = 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_rdonly(sb)) {
+ 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 *, unsigned *) = {
+ [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, &sb->s_max_links);
+
+ 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 |= SB_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_make_root(root_inode);
+ if (!sb->s_root) {
+ 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;
+ mutex_init(&sbi->s_lock);
+ 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;
+ mutex_init(&sbi->s_lock);
+ 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,
+};
+MODULE_ALIAS_FS("sysv");
+
+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,
+};
+MODULE_ALIAS_FS("v7");
+MODULE_ALIAS("v7");
+
+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_LICENSE("GPL");
diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h
new file mode 100644
index 0000000..e913698
--- /dev/null
+++ b/fs/sysv/sysv.h
@@ -0,0 +1,247 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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) */
+ 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;
+ struct mutex s_lock;
+};
+
+/*
+ * 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 container_of(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);
+}
+
+
+/* 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 *, umode_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(const struct path *, struct kstat *, u32, unsigned int);
+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 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 */