o Everybody needs dm.h

o Fixed to work with highmem
 o Added dmfs private inode struct for lv and table directories
 o Fixed a number of errors/typos
 o Status file read returns 0 so we can leave this until we've actually got
   something to report in this now.
 o New locking on tables.... still some issues to be worked out here but
   closer now I think.
 o Now use mapping of table directory to hold pages rather than mapping of
   table file inode. Need to write a note to myself to fix issues with the
   file length at the same time....

Well thats enough for tonight I think. The error file will be part of
tomorrows work.

driver/device-mapper/dmfs-error.c

@@ -22,6 +22,19 @@
 #include <linux/config.h>
 #include <linux/fs.h>
 
+#include "dm.h"
+
+void dmfs_add_error(struct dm_table *t, unsigned num, char *str)
+{
+
+}
+
+/* 
+ * Assuming that we allow modules to call this rather than passing the message
+ * back. Not sure which approach to take yet.
+ */
+EXPORT_SYMBOL(dmfs_add_error);
+
 static ssize_t dmfs_error_read(struct file *file, char *buf, size_t size, loff_t *pos)
 {
 	struct dmfs_i *dmi = DMFS_I(file->f_dentry->d_parent->d_inode);
@@ -31,6 +44,11 @@ static ssize_t dmfs_error_read(struct file *file, char *buf, size_t size, loff_t
 	if (!access_ok(VERIFY_WRITE, buf, count))
 		return -EFAULT;
 
+	down(&dmi->sem);
+	if (dmi->table) {
+
+	}
+	up(&dmi->sem);
 	return copied;
 }
 

driver/device-mapper/dmfs-lv.c

@@ -25,6 +25,8 @@
 #include <linux/ctype.h>
 #include <linux/fs.h>
 
+#include "dm.h"
+
 extern struct dmfs_address_space_operations;
 
 struct dentry *dmfs_verify_name(struct inode *dir, char *name)
@@ -73,8 +75,10 @@ struct inode *dmfs_create_symlink(struct inode *dir, int mode)
 	return inode;
 }
 
-static int dmfs_lv_unlink(struct inode *inode, struct dentry *dentry)
+static int dmfs_lv_unlink(struct inode *dir, struct dentry *dentry)
 {
+	struct inode *inode = dentry->d_inode;
+
 	if (!(inode->i_mode & S_IFLNK))
 		return -EINVAL;
 
@@ -229,16 +233,9 @@ static struct dm_root_inode_operations = {
 
 struct inode *dmfs_create_lv(struct super_block *sb, int mode)
 {
-	struct inode *inode = new_inode(sb);
+	struct inode *inode = dmfs_new_inode(sb, mode | S_IFDIR);
 
 	if (inode) {
-		inode->i_mode = mode | S_IFDIR;
-		inode->i_uid = current->fsuid;
-		inode->i_gid = current->fsgid;
-		inode->i_blksize = PAGE_CACHE_SIZE;
-		inode->i_blocks = 0;
-		inode->i_rdev = NODEV;
-		inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
 		inode->i_fop = &dmfs_lv_file_operations;
 		inode->i_op = &dmfs_lv_dir_operations;
 	}

driver/device-mapper/dmfs-root.c

@@ -25,6 +25,8 @@
 #include <linux/ctype.h>
 #include <linux/fs.h>
 
+#include "dm.h"
+
 static int is_identifier(const char *str, int len)
 {
 	while(len--) {

driver/device-mapper/dmfs-status.c

@@ -24,7 +24,7 @@
 
 static ssize_t dmfs_status_read(struct file *file, char *buf, size_t size, loff_t *pos)
 {
-	return size;
+	return 0;
 }
 
 static int dmfs_status_sync(struct file *file, struct dentry *dentry, int datasync)

driver/device-mapper/dmfs-super.c

@@ -22,6 +22,8 @@
 #include <linux/config.h>
 #include <linux/fs.h>
 
+#include "dm.h"
+
 #define DMFS_MAGIC 0x444D4653
 
 extern struct inode *dmfs_create_root(struct super_block *sb, int);
@@ -84,4 +86,28 @@ struct super_block *dmfs_read_super(struct super_block *sb, void *data, int sile
 	return sb;
 }
 
+struct inode *dmfs_new_inode(struct super_block *sb, int mode)
+{
+	struct inode *inode = new_inode(sb);
+	struct dmfs_i *dmi;
 
+	if (inode) {
+		inode->i_mode = mode;
+		inode->i_uid = current->fsuid;
+		inode->i_gid = current->fsgid;
+		inode->i_blksize = PAGE_CACHE_SIZE;
+		inode->i_blocks = 0;
+		inode->i_rdev = NODEV;
+		inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
+
+		dmi = kmalloc(sizeof(struct dmfs_i), GFP_KERNEL);
+		if (dmi == NULL) {
+			iput(inode);
+			return NULL;
+		}
+		memset(dmi, sizeof(struct dmfs_i), 0);
+		init_MUTEX(&dmi->sem);
+		inode->generic_ip = dmi;
+	}
+	return inode;
+}

driver/device-mapper/dmfs-table.c

@@ -21,9 +21,8 @@
 
 #include <linux/config.h>
 #include <linux/fs.h>
-#include <linux/parser.h>
-#include "dm.h"
 
+#include "dm.h"
 
 static inline char *next_token(char **p)
 {
@@ -37,43 +36,65 @@ static inline char *next_token(char **p)
 	return r;
 }
 
-static int dmfs_parse_line(struct dmfs_table *t, char *str)
+static offset_t start_of_next_range(struct dm_table *t)
+{
+	offset_t n = 0;
+	if (t->num_targets) {
+		n = t->highs[t->num_targets - 1] + 1;
+	}
+	return n;
+}
+
+static void dmfs_parse_line(struct dmfs_table *t, unsigned num, char *str)
 {
 	char *p = str;
-	const char *delim = " \t";
 	const char *tok;
 	offset_t start, size, high;
 	void *context;
 	struct target_type *ttype;
+	int rv = 0;
+	char *msg;
 
+	msg = "No start argument";
 	tok = next_token(&p);
 	if (!tok)
-		return -1;
+		goto out;
 	start = simple_strtoul(tok, NULL, 10);
 
+	msg = "No size argument";
 	tok = next_token(&p);
 	if (!tok)
-		return -1;
+		goto out;
 	size = simple_strtoul(tok, NULL, 10);
 
+	msg = "Gap in table";
+	if (start != start_of_next_range(t))
+		goto out;
+
+	msg = "No target type";
 	tok = next_token(&p);
 	if (!tok)
-		return -1;
+		goto out;
 
+	msg = "Target type unknown";
 	ttype = dm_get_target_type(tok);
 	if (ttype) {
-		context = ttype->ctr(t, start, size, p);
-		if (!IS_ERR(context)) {
+		msg = "This message should never appear (constructor error)";
+		rv = ttype->ctr(t, start, size, p, &context);
+		if (rv == 0)) {
+			msg = "Error adding target to table";
 			high = start + (size - 1);
 			if (dm_table_add_target(t, high, ttype, context) == 0)
-				return 0;
+				return;
 			ttype->dtr(t, context);
 		}
 		dm_put_target_type(ttype);
 	}
-	return -1;
+out:
+	dmfs_add_error(t, num, msg);
 }
 
+
 static int dmfs_copy(char *dst, int dstlen, char *src, int srclen, int *flag)
 {
 	int copied = 0;
@@ -95,7 +116,7 @@ end_of_line:
 	goto out;
 }
 
-static int dmfs_parse_page(struct dm_table *t, char *buf, int len, char *tmp, unsigned long *tmpl)
+static int dmfs_parse_page(struct dm_table *t, char *buf, int len, char *tmp, unsigned long *tmpl, int *num)
 {
 	int copied;
 
@@ -105,15 +126,20 @@ static int dmfs_parse_page(struct dm_table *t, char *buf, int len, char *tmp, un
 		buf += copied;
 		len -= copied;
 		if (*tmpl + copied == PAGE_SIZE - 1)
-			return -1;
+			goto line_too_long;
 		*tmpl = copied;
 		if (flag) {
-			if (dmfs_parse_line(t, tmp))
-				return -1;
+			dmfs_parse_line(t, *num, tmp);
+			(*num)++;
 			*tmpl = 0;
 		}
 	} while(len > 0);
 	return 0;
+
+line_too_long:
+	dmfs_add_error(t, *num, "Line too long");
+	/* FIXME: Add code to recover from this */
+	return -1;
 }
 
 static struct dm_table *dmfs_parse(struct inode *inode)
@@ -126,6 +152,7 @@ static struct dm_table *dmfs_parse(struct inode *inode)
 	unsigned long rem = 0;
 	struct dm_table *t;
 	struct page *pg, **hash;
+	int num = 0;
 
 	if (inode->i_size == 0)
 		return NULL;
@@ -141,9 +168,8 @@ static struct dm_table *dmfs_parse(struct inode *inode)
 		return NULL;
 	}
 
-	down(&inode->i_sem);
-	end_index = inode->i_size >> PAGE_CACHE_SIZE;
-	end_offset = inode->i_size & (PAGE_CAHE_SIZE - 1);
+	end_index = inode->i_size >> PAGE_CACHE_SHIFT;
+	end_offset = inode->i_size & (PAGE_CACHE_SIZE - 1);
 
 	do {
 		unsigned long end = (index == end_index) ? end_offset : PAGE_CACHE_SIZE;
@@ -156,10 +182,17 @@ static struct dm_table *dmfs_parse(struct inode *inode)
 		spin_unlock(&pagecache_lock);
 
 		if (pg) {
+			char *kaddr;
+			int rv;
+
 			if (!Page_Uptodate(pg))
 				goto broken;
 
-			if (dmfs_parse_page(t, pg, end, (char *)page, &rem))
+			kaddr = kmap(pg);
+			rv = dmfs_parse_page(t, kaddr, end, (char *)page, &rem);
+			kunmap(pg);
+
+			if (rv)
 				goto parse_error;
 		}
 
@@ -167,8 +200,6 @@ static struct dm_table *dmfs_parse(struct inode *inode)
 		index++;
 	} while(index != end_index);
 
-	up(&inode->i_sem);
-
 	free_page(page);
 	if (dm_table_complete(t) == 0)
 		return t;
@@ -177,14 +208,12 @@ static struct dm_table *dmfs_parse(struct inode *inode)
 	return NULL;
 
 broken:
-	up(&inode->i_sem);
 	printk(KERN_ERR "dmfs_parse: Page not uptodate\n");
 	free_page(page);
 	dm_put_table(t);
 	return NULL;
 
 parse_error:
-	up(&inode->i_sem);
 	printk(KERN_ERR "dmfs_parse: Parse error\n");
 	free_page(page);
 	dm_put_table(t);
@@ -193,17 +222,21 @@ parse_error:
 
 static int dmfs_release(struct inode *inode, struct file *f)
 {
+	struct dmfs_i *dmi = inode->u.generic_ip;
 	struct dm_table *table;
 
 	if (!(f->f_mode & S_IWUGO))
 		return 0;
 
+	down(&dmi->sem);
 	table = dmfs_parse(inode);
 
 	if (table) {
-		dm_put_table((struct dm_table *)inode->u.generic_ip);
-		inode->u.generic_ip = table;
+		if (dmi->table)
+			dm_put_table(dmi->table);
+		dmi->table = table;
 	}
+	up(&dmi->sem);
 
 	return 0;
 }
@@ -290,7 +323,7 @@ struct dmfs_address_space_operations = {
 static struct dmfs_table_file_operations = {
  	llseek:		generic_file_llseek,
 	read:		generic_file_read,
-	write:		generic_file_write,
+	write:		generic_file_write, /* FIXME: Needs to hold dmi->sem */
 	open:		dmfs_table_open,
 	release:	dmfs_table_release,
 	fsync:		dmfs_table_sync,
@@ -315,6 +348,7 @@ int dmfs_create_table(struct inode *dir, int mode)
 		inode->i_mapping->a_ops = &dmfs_address_space_operations;
 		inode->i_fop = &dmfs_table_file_operations;
 		inode->i_op = &dmfs_table_inode_operations;
+		inode->i_mapping = dir->i_mapping;
 	}
 
 	return inode;

driver/device-mapper/dmfs-tdir.c

@@ -24,6 +24,8 @@
 #include <linux/config.h>
 #include <linux/fs.h>
 
+#include "dm.h"
+
 extern struct inode *dmfs_create_error(struct inode *, int);
 extern struct inode *dmfs_create_table(struct inode *, int);
 extern struct inode *dmfs_create_status(struct inode *, int);
@@ -45,6 +47,9 @@ void dm_unlock_tdir(struct dentry *dentry)
 
 static int dmfs_tdir_unlink(struct inode *dir, struct dentry *dentry)
 {
+	struct inode *inode = dentry->d_inode;
+
+	inode->i_mapping = &inode->i_data;
 	inode->i_nlink--;
 	dput(dentry);
 	return 0;
@@ -131,16 +136,9 @@ static struct dmfs_tdir_inode_operations = {
 
 struct inode *dmfs_create_tdir(struct inode *dir, struct dentry *dentry, int mode)
 {
-	struct inode *inode = new_inode(sb);
+	struct inode *inode = dmfs_new_inode(sb, mode | S_IFDIR);
 
 	if (inode) {
-		inode->i_mode = mode | S_IFDIR;
-		inode->i_uid = current->fsuid;
-		inode->i_gid = current->fsgid;
-		inode->i_blksize = PAGE_CACHE_SIZE;
-		inode->i_blocks = 0;
-		inode->i_rdev = NODEV;
-		inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
 		inode->i_fop = &dmfs_tdir_file_operations;
 		inode->i_op = &dmfs_tdir_dir_operations;
 	}