7 files changed, 106 insertions, 55 deletions

diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index 79941e4964a4..a77c42157620 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -218,8 +218,7 @@ got_it:
         pos = page_offset(page) +
                         (char*)de - (char*)page_address(page);
         lock_page(page);
-        err = __sysv_write_begin(NULL, page->mapping, pos, SYSV_DIRSIZE,
-                                AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
+        err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
         if (err)
                 goto out_unlock;
         memcpy (de->name, name, namelen);
@@ -239,15 +238,13 @@ out_unlock:
 
 int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page)
 {
-        struct address_space *mapping = page->mapping;
-        struct inode *inode = (struct inode*)mapping->host;
+        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_write_begin(NULL, mapping, pos, SYSV_DIRSIZE,
-                                AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
+        err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
         BUG_ON(err);
         de->inode = 0;
         err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
@@ -259,16 +256,14 @@ int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page)
 
 int sysv_make_empty(struct inode *inode, struct inode *dir)
 {
-        struct address_space *mapping = inode->i_mapping;
-        struct page *page = grab_cache_page(mapping, 0);
+        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_write_begin(NULL, mapping, 0, 2 * SYSV_DIRSIZE,
-                                AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
+        err = sysv_prepare_chunk(page, 0, 2 * SYSV_DIRSIZE);
         if (err) {
                 unlock_page(page);
                 goto fail;
@@ -341,15 +336,13 @@ not_empty:
 void sysv_set_link(struct sysv_dir_entry *de, struct page *page,
         struct inode *inode)
 {
-        struct address_space *mapping = page->mapping;
-        struct inode *dir = mapping->host;
+        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_write_begin(NULL, mapping, pos, SYSV_DIRSIZE,
-                                AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
+        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);
diff --git a/fs/sysv/file.c b/fs/sysv/file.c
index 750cc22349bd..0a65939508e9 100644
--- a/fs/sysv/file.c
+++ b/fs/sysv/file.c
@@ -30,7 +30,29 @@ const struct file_operations sysv_file_operations = {
         .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
index fcc498ec9b33..0c96c98bd1db 100644
--- a/fs/sysv/ialloc.c
+++ b/fs/sysv/ialloc.c
@@ -113,7 +113,6 @@ void sysv_free_inode(struct inode * inode)
                 return;
         }
         raw_inode = sysv_raw_inode(sb, ino, &bh);
-        clear_inode(inode);
         if (!raw_inode) {
                 printk("sysv_free_inode: unable to read inode block on device "
                        "%s\n", inode->i_sb->s_id);
diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index d4a5380b5669..de44d067b9e6 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -71,8 +71,8 @@ static int sysv_remount(struct super_block *sb, int *flags, char *data)
         lock_super(sb);
         if (sbi->s_forced_ro)
                 *flags |= MS_RDONLY;
-        if (!(*flags & MS_RDONLY))
-                sb->s_dirt = 1;
+        if (*flags & MS_RDONLY)
+                sysv_write_super(sb);
         unlock_super(sb);
         return 0;
 }
@@ -308,12 +308,17 @@ int sysv_sync_inode(struct inode *inode)
         return __sysv_write_inode(inode, 1);
 }
 
-static void sysv_delete_inode(struct inode *inode)
+static void sysv_evict_inode(struct inode *inode)
 {
         truncate_inode_pages(&inode->i_data, 0);
-        inode->i_size = 0;
-        sysv_truncate(inode);
-        sysv_free_inode(inode);
+        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;
@@ -344,7 +349,7 @@ const struct super_operations sysv_sops = {
         .alloc_inode    = sysv_alloc_inode,
         .destroy_inode  = sysv_destroy_inode,
         .write_inode    = sysv_write_inode,
-        .delete_inode   = sysv_delete_inode,
+        .evict_inode    = sysv_evict_inode,
         .put_super      = sysv_put_super,
         .write_super    = sysv_write_super,
         .sync_fs        = sysv_sync_fs,
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c
index f042eec464c2..9ca66276315e 100644
--- a/fs/sysv/itree.c
+++ b/fs/sysv/itree.c
@@ -459,20 +459,25 @@ static int sysv_readpage(struct file *file, struct page *page)
         return block_read_full_page(page,get_block);
 }
 
-int __sysv_write_begin(struct file *file, struct address_space *mapping,
-                        loff_t pos, unsigned len, unsigned flags,
-                        struct page **pagep, void **fsdata)
+int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len)
 {
-        return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
-                                get_block);
+        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)
 {
-        *pagep = NULL;
-        return __sysv_write_begin(file, mapping, pos, len, flags, pagep, 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)
diff --git a/fs/sysv/super.c b/fs/sysv/super.c
index 5a903da54551..85359a8df605 100644
--- a/fs/sysv/super.c
+++ b/fs/sysv/super.c
@@ -24,6 +24,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/buffer_head.h>
+#include <linux/parser.h>
 #include "sysv.h"
 
 /*
@@ -347,7 +348,6 @@ static int complete_read_super(struct super_block *sb, int silent, int size)
                 sb->s_flags |= MS_RDONLY;
         if (sbi->s_truncate)
                 sb->s_root->d_op = &sysv_dentry_operations;
-        sb->s_dirt = 1;
         return 1;
 }
 
@@ -435,12 +435,46 @@ Ebadsize:
         goto failed;
 }
 
-static int v7_fill_super(struct super_block *sb, void *data, int silent)
+static int v7_sanity_check(struct super_block *sb, struct buffer_head *bh)
 {
-        struct sysv_sb_info *sbi;
-        struct buffer_head *bh, *bh2 = NULL;
         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");
@@ -454,7 +488,6 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
         sbi->s_sb = sb;
         sbi->s_block_base = 0;
         sbi->s_type = FSTYPE_V7;
-        sbi->s_bytesex = BYTESEX_PDP;
         sb->s_fs_info = sbi;
         
         sb_set_blocksize(sb, 512);
@@ -466,32 +499,27 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
                 goto failed;
         }
 
-        /* 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_time) == 0)
-                goto failed;
+        /* Try PDP-11 UNIX */
+        sbi->s_bytesex = BYTESEX_PDP;
+        if (v7_sanity_check(sb, bh))
+                goto detected;
 
-        /* plausibility check on root inode: it is a directory,
-           with a nonzero size that is a multiple of 16 */
-        if ((bh2 = sb_bread(sb, 2)) == NULL)
-                goto failed;
-        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) != 0)
-                goto failed;
-        brelse(bh2);
-        bh2 = NULL;
+        /* 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:
-        brelse(bh2);
+        printk(KERN_ERR "VFS: could not find a valid V7 on %s.\n",
+                sb->s_id);
         brelse(bh);
         kfree(sbi);
         return -EINVAL;
@@ -560,4 +588,5 @@ static void __exit exit_sysv_fs(void)
 
 module_init(init_sysv_fs)
 module_exit(exit_sysv_fs)
+MODULE_ALIAS("v7");
 MODULE_LICENSE("GPL");
diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h
index 94cb9b4d76c2..bb55cdb394bf 100644
--- a/fs/sysv/sysv.h
+++ b/fs/sysv/sysv.h
@@ -136,9 +136,7 @@ extern unsigned long sysv_count_free_blocks(struct super_block *);
 
 /* itree.c */
 extern void sysv_truncate(struct inode *);
-extern int __sysv_write_begin(struct file *file, struct address_space *mapping,
-                        loff_t pos, unsigned len, unsigned flags,
-                        struct page **pagep, void **fsdata);
+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);