1 files changed, 196 insertions, 56 deletions

diff --git a/drivers/scsi/scsi_proc.c b/drivers/scsi/scsi_proc.c
index 07be62bbaae..86f0c5d5c11 100644
--- a/drivers/scsi/scsi_proc.c
+++ b/drivers/scsi/scsi_proc.c
@@ -20,12 +20,12 @@
 #include <linux/init.h>
 #include <linux/string.h>
 #include <linux/mm.h>
-#include <linux/slab.h>
 #include <linux/proc_fs.h>
 #include <linux/errno.h>
 #include <linux/blkdev.h>
 #include <linux/seq_file.h>
 #include <linux/mutex.h>
+#include <linux/gfp.h>
 #include <asm/uaccess.h>
 
 #include <scsi/scsi.h>
@@ -45,44 +45,61 @@ static struct proc_dir_entry *proc_scsi;
 /* Protect sht->present and sht->proc_dir */
 static DEFINE_MUTEX(global_host_template_mutex);
 
-static int proc_scsi_read(char *buffer, char **start, off_t offset,
-			  int length, int *eof, void *data)
+static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
+                           size_t count, loff_t *ppos)
 {
-	struct Scsi_Host *shost = data;
-	int n;
-
-	n = shost->hostt->proc_info(shost, buffer, start, offset, length, 0);
-	*eof = (n < length);
-
-	return n;
-}
-
-static int proc_scsi_write_proc(struct file *file, const char __user *buf,
-                           unsigned long count, void *data)
-{
-	struct Scsi_Host *shost = data;
+	struct Scsi_Host *shost = PDE_DATA(file_inode(file));
 	ssize_t ret = -ENOMEM;
 	char *page;
-	char *start;
     
 	if (count > PROC_BLOCK_SIZE)
 		return -EOVERFLOW;
 
+	if (!shost->hostt->write_info)
+		return -EINVAL;
+
 	page = (char *)__get_free_page(GFP_KERNEL);
 	if (page) {
 		ret = -EFAULT;
 		if (copy_from_user(page, buf, count))
 			goto out;
-		ret = shost->hostt->proc_info(shost, page, &start, 0, count, 1);
+		ret = shost->hostt->write_info(shost, page, count);
 	}
 out:
 	free_page((unsigned long)page);
 	return ret;
 }
 
+static int proc_scsi_show(struct seq_file *m, void *v)
+{
+	struct Scsi_Host *shost = m->private;
+	return shost->hostt->show_info(m, shost);
+}
+
+static int proc_scsi_host_open(struct inode *inode, struct file *file)
+{
+	return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
+				4 * PAGE_SIZE);
+}
+
+static const struct file_operations proc_scsi_fops = {
+	.open = proc_scsi_host_open,
+	.release = single_release,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.write = proc_scsi_host_write
+};
+
+/**
+ * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
+ * @sht: owner of this directory
+ *
+ * Sets sht->proc_dir to the new directory.
+ */
+
 void scsi_proc_hostdir_add(struct scsi_host_template *sht)
 {
-	if (!sht->proc_info)
+	if (!sht->show_info)
 		return;
 
 	mutex_lock(&global_host_template_mutex);
@@ -90,16 +107,18 @@ void scsi_proc_hostdir_add(struct scsi_host_template *sht)
 		sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
         	if (!sht->proc_dir)
 			printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
-			       __FUNCTION__, sht->proc_name);
-		else
-			sht->proc_dir->owner = sht->module;
+			       __func__, sht->proc_name);
 	}
 	mutex_unlock(&global_host_template_mutex);
 }
 
+/**
+ * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
+ * @sht: owner of directory
+ */
 void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
 {
-	if (!sht->proc_info)
+	if (!sht->show_info)
 		return;
 
 	mutex_lock(&global_host_template_mutex);
@@ -110,6 +129,11 @@ void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
 	mutex_unlock(&global_host_template_mutex);
 }
 
+
+/**
+ * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
+ * @shost: host to add
+ */
 void scsi_proc_host_add(struct Scsi_Host *shost)
 {
 	struct scsi_host_template *sht = shost->hostt;
@@ -120,19 +144,18 @@ void scsi_proc_host_add(struct Scsi_Host *shost)
 		return;
 
 	sprintf(name,"%d", shost->host_no);
-	p = create_proc_read_entry(name, S_IFREG | S_IRUGO | S_IWUSR,
-			sht->proc_dir, proc_scsi_read, shost);
-	if (!p) {
+	p = proc_create_data(name, S_IRUGO | S_IWUSR,
+		sht->proc_dir, &proc_scsi_fops, shost);
+	if (!p)
 		printk(KERN_ERR "%s: Failed to register host %d in"
-		       "%s\n", __FUNCTION__, shost->host_no,
+		       "%s\n", __func__, shost->host_no,
 		       sht->proc_name);
-		return;
-	} 
-
-	p->write_proc = proc_scsi_write_proc;
-	p->owner = sht->module;
 }
 
+/**
+ * scsi_proc_host_rm - remove this host's entry from /proc
+ * @shost: which host
+ */
 void scsi_proc_host_rm(struct Scsi_Host *shost)
 {
 	char name[10];
@@ -143,13 +166,24 @@ void scsi_proc_host_rm(struct Scsi_Host *shost)
 	sprintf(name,"%d", shost->host_no);
 	remove_proc_entry(name, shost->hostt->proc_dir);
 }
-
+/**
+ * proc_print_scsidevice - return data about this host
+ * @dev: A scsi device
+ * @data: &struct seq_file to output to.
+ *
+ * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
+ * and revision.
+ */
 static int proc_print_scsidevice(struct device *dev, void *data)
 {
-	struct scsi_device *sdev = to_scsi_device(dev);
+	struct scsi_device *sdev;
 	struct seq_file *s = data;
 	int i;
 
+	if (!scsi_is_sdev_device(dev))
+		goto out;
+
+	sdev = to_scsi_device(dev);
 	seq_printf(s,
 		"Host: scsi%d Channel: %02d Id: %02d Lun: %02d\n  Vendor: ",
 		sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
@@ -178,28 +212,41 @@ static int proc_print_scsidevice(struct device *dev, void *data)
 
 	seq_printf(s, "\n");
 
-	seq_printf(s, "  Type:   %s ",
-		     sdev->type < MAX_SCSI_DEVICE_CODE ?
-	       scsi_device_types[(int) sdev->type] : "Unknown          ");
-	seq_printf(s, "               ANSI"
-		     " SCSI revision: %02x", (sdev->scsi_level - 1) ?
-		     sdev->scsi_level - 1 : 1);
+	seq_printf(s, "  Type:   %s ", scsi_device_type(sdev->type));
+	seq_printf(s, "               ANSI  SCSI revision: %02x",
+			sdev->scsi_level - (sdev->scsi_level > 1));
 	if (sdev->scsi_level == 2)
 		seq_printf(s, " CCS\n");
 	else
 		seq_printf(s, "\n");
 
+out:
 	return 0;
 }
 
+/**
+ * scsi_add_single_device - Respond to user request to probe for/add device
+ * @host: user-supplied decimal integer
+ * @channel: user-supplied decimal integer
+ * @id: user-supplied decimal integer
+ * @lun: user-supplied decimal integer
+ *
+ * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
+ *
+ * does scsi_host_lookup() and either user_scan() if that transport
+ * type supports it, or else scsi_scan_host_selected()
+ *
+ * Note: this seems to be aimed exclusively at SCSI parallel busses.
+ */
+
 static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
 {
 	struct Scsi_Host *shost;
 	int error = -ENXIO;
 
 	shost = scsi_host_lookup(host);
-	if (IS_ERR(shost))
-		return PTR_ERR(shost);
+	if (!shost)
+		return error;
 
 	if (shost->transportt->user_scan)
 		error = shost->transportt->user_scan(shost, channel, id, lun);
@@ -209,6 +256,16 @@ static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
 	return error;
 }
 
+/**
+ * scsi_remove_single_device - Respond to user request to remove a device
+ * @host: user-supplied decimal integer
+ * @channel: user-supplied decimal integer
+ * @id: user-supplied decimal integer
+ * @lun: user-supplied decimal integer
+ *
+ * Description: called by writing "scsi remove-single-device" to
+ * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
+ */
 static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
 {
 	struct scsi_device *sdev;
@@ -216,8 +273,8 @@ static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
 	int error = -ENXIO;
 
 	shost = scsi_host_lookup(host);
-	if (IS_ERR(shost))
-		return PTR_ERR(shost);
+	if (!shost)
+		return error;
 	sdev = scsi_device_lookup(shost, channel, id, lun);
 	if (sdev) {
 		scsi_remove_device(sdev);
@@ -229,6 +286,25 @@ static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
 	return error;
 }
 
+/**
+ * proc_scsi_write - handle writes to /proc/scsi/scsi
+ * @file: not used
+ * @buf: buffer to write
+ * @length: length of buf, at most PAGE_SIZE
+ * @ppos: not used
+ *
+ * Description: this provides a legacy mechanism to add or remove devices by
+ * Host, Channel, ID, and Lun.  To use,
+ * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
+ * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
+ * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
+ *
+ * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
+ * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
+ * provide a unique identifier and nothing more.
+ */
+
+
 static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
 			       size_t length, loff_t *ppos)
 {
@@ -266,8 +342,6 @@ static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
 		lun = simple_strtoul(p + 1, &p, 0);
 
 		err = scsi_add_single_device(host, channel, id, lun);
-		if (err >= 0)
-			err = length;
 
 	/*
 	 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
@@ -284,35 +358,99 @@ static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
 		err = scsi_remove_single_device(host, channel, id, lun);
 	}
 
+	/*
+	 * convert success returns so that we return the 
+	 * number of bytes consumed.
+	 */
+	if (!err)
+		err = length;
+
  out:
 	free_page((unsigned long)buffer);
 	return err;
 }
 
-static int proc_scsi_show(struct seq_file *s, void *p)
+static int always_match(struct device *dev, void *data)
 {
-	seq_printf(s, "Attached devices:\n");
-	bus_for_each_dev(&scsi_bus_type, NULL, s, proc_print_scsidevice);
-	return 0;
+	return 1;
+}
+
+static inline struct device *next_scsi_device(struct device *start)
+{
+	struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
+					      always_match);
+	put_device(start);
+	return next;
+}
+
+static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
+{
+	struct device *dev = NULL;
+	loff_t n = *pos;
+
+	while ((dev = next_scsi_device(dev))) {
+		if (!n--)
+			break;
+		sfile->private++;
+	}
+	return dev;
+}
+
+static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
+{
+	(*pos)++;
+	sfile->private++;
+	return next_scsi_device(v);
+}
+
+static void scsi_seq_stop(struct seq_file *sfile, void *v)
+{
+	put_device(v);
+}
+
+static int scsi_seq_show(struct seq_file *sfile, void *dev)
+{
+	if (!sfile->private)
+		seq_puts(sfile, "Attached devices:\n");
+
+	return proc_print_scsidevice(dev, sfile);
 }
 
+static const struct seq_operations scsi_seq_ops = {
+	.start	= scsi_seq_start,
+	.next	= scsi_seq_next,
+	.stop	= scsi_seq_stop,
+	.show	= scsi_seq_show
+};
+
+/**
+ * proc_scsi_open - glue function
+ * @inode: not used
+ * @file: passed to single_open()
+ *
+ * Associates proc_scsi_show with this file
+ */
 static int proc_scsi_open(struct inode *inode, struct file *file)
 {
 	/*
-	 * We don't really needs this for the write case but it doesn't
+	 * We don't really need this for the write case but it doesn't
 	 * harm either.
 	 */
-	return single_open(file, proc_scsi_show, NULL);
+	return seq_open(file, &scsi_seq_ops);
 }
 
-static struct file_operations proc_scsi_operations = {
+static const struct file_operations proc_scsi_operations = {
+	.owner		= THIS_MODULE,
 	.open		= proc_scsi_open,
 	.read		= seq_read,
 	.write		= proc_scsi_write,
 	.llseek		= seq_lseek,
-	.release	= single_release,
+	.release	= seq_release,
 };
 
+/**
+ * scsi_init_procfs - create scsi and scsi/scsi in procfs
+ */
 int __init scsi_init_procfs(void)
 {
 	struct proc_dir_entry *pde;
@@ -321,10 +459,9 @@ int __init scsi_init_procfs(void)
 	if (!proc_scsi)
 		goto err1;
 
-	pde = create_proc_entry("scsi/scsi", 0, NULL);
+	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
 	if (!pde)
 		goto err2;
-	pde->proc_fops = &proc_scsi_operations;
 
 	return 0;
 
@@ -334,6 +471,9 @@ err1:
 	return -ENOMEM;
 }
 
+/**
+ * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
+ */
 void scsi_exit_procfs(void)
 {
 	remove_proc_entry("scsi/scsi", NULL);