1 files changed, 109 insertions, 106 deletions

diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 2311019304c0..7aad15436d24 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -21,6 +21,7 @@
 #include <linux/compat.h>
 #include <linux/chio.h>                 /* here are all the ioctls */
 #include <linux/mutex.h>
+#include <linux/idr.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -33,6 +34,7 @@
 
 #define CH_DT_MAX       16
 #define CH_TYPES        8
+#define CH_MAX_DEVS     128
 
 MODULE_DESCRIPTION("device driver for scsi media changer devices");
 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org>");
@@ -88,17 +90,6 @@ static const char * vendor_labels[CH_TYPES-4] = {
 
 #define MAX_RETRIES   1
 
-static int  ch_probe(struct device *);
-static int  ch_remove(struct device *);
-static int  ch_open(struct inode * inode, struct file * filp);
-static int  ch_release(struct inode * inode, struct file * filp);
-static int  ch_ioctl(struct inode * inode, struct file * filp,
-                     unsigned int cmd, unsigned long arg);
-#ifdef CONFIG_COMPAT
-static long ch_ioctl_compat(struct file * filp,
-                            unsigned int cmd, unsigned long arg);
-#endif
-
 static struct class * ch_sysfs_class;
 
 typedef struct {
@@ -114,30 +105,8 @@ typedef struct {
         struct mutex        lock;
 } scsi_changer;
 
-static LIST_HEAD(ch_devlist);
-static DEFINE_SPINLOCK(ch_devlist_lock);
-static int ch_devcount;
-
-static struct scsi_driver ch_template =
-{
-        .owner          = THIS_MODULE,
-        .gendrv         = {
-                .name   = "ch",
-                .probe  = ch_probe,
-                .remove = ch_remove,
-        },
-};
-
-static const struct file_operations changer_fops =
-{
-        .owner        = THIS_MODULE,
-        .open         = ch_open,
-        .release      = ch_release,
-        .ioctl        = ch_ioctl,
-#ifdef CONFIG_COMPAT
-        .compat_ioctl = ch_ioctl_compat,
-#endif
-};
+static DEFINE_IDR(ch_index_idr);
+static DEFINE_SPINLOCK(ch_index_lock);
 
 static const struct {
         unsigned char  sense;
@@ -207,7 +176,7 @@ ch_do_scsi(scsi_changer *ch, unsigned char *cmd,
 {
         int errno, retries = 0, timeout, result;
         struct scsi_sense_hdr sshdr;
-        
+
         timeout = (cmd[0] == INITIALIZE_ELEMENT_STATUS)
                 ? timeout_init : timeout_move;
 
@@ -245,7 +214,7 @@ static int
 ch_elem_to_typecode(scsi_changer *ch, u_int elem)
 {
         int i;
-        
+
         for (i = 0; i < CH_TYPES; i++) {
                 if (elem >= ch->firsts[i]  &&
                     elem <  ch->firsts[i] +
@@ -261,15 +230,15 @@ ch_read_element_status(scsi_changer *ch, u_int elem, char *data)
         u_char  cmd[12];
         u_char  *buffer;
         int     result;
-        
+
         buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
         if(!buffer)
                 return -ENOMEM;
-        
+
  retry:
         memset(cmd,0,sizeof(cmd));
         cmd[0] = READ_ELEMENT_STATUS;
-        cmd[1] = (ch->device->lun << 5) | 
+        cmd[1] = (ch->device->lun << 5) |
                 (ch->voltags ? 0x10 : 0) |
                 ch_elem_to_typecode(ch,elem);
         cmd[2] = (elem >> 8) & 0xff;
@@ -296,7 +265,7 @@ ch_read_element_status(scsi_changer *ch, u_int elem, char *data)
         return result;
 }
 
-static int 
+static int
 ch_init_elem(scsi_changer *ch)
 {
         int err;
@@ -322,7 +291,7 @@ ch_readconfig(scsi_changer *ch)
         buffer = kzalloc(512, GFP_KERNEL | GFP_DMA);
         if (!buffer)
                 return -ENOMEM;
-        
+
         memset(cmd,0,sizeof(cmd));
         cmd[0] = MODE_SENSE;
         cmd[1] = ch->device->lun << 5;
@@ -365,7 +334,7 @@ ch_readconfig(scsi_changer *ch)
         } else {
                 vprintk("reading element address assigment page failed!\n");
         }
-        
+
         /* vendor specific element types */
         for (i = 0; i < 4; i++) {
                 if (0 == vendor_counts[i])
@@ -443,7 +412,7 @@ static int
 ch_position(scsi_changer *ch, u_int trans, u_int elem, int rotate)
 {
         u_char  cmd[10];
-        
+
         dprintk("position: 0x%x\n",elem);
         if (0 == trans)
                 trans = ch->firsts[CHET_MT];
@@ -462,7 +431,7 @@ static int
 ch_move(scsi_changer *ch, u_int trans, u_int src, u_int dest, int rotate)
 {
         u_char  cmd[12];
-        
+
         dprintk("move: 0x%x => 0x%x\n",src,dest);
         if (0 == trans)
                 trans = ch->firsts[CHET_MT];
@@ -484,7 +453,7 @@ ch_exchange(scsi_changer *ch, u_int trans, u_int src,
             u_int dest1, u_int dest2, int rotate1, int rotate2)
 {
         u_char  cmd[12];
-        
+
         dprintk("exchange: 0x%x => 0x%x => 0x%x\n",
                 src,dest1,dest2);
         if (0 == trans)
@@ -501,7 +470,7 @@ ch_exchange(scsi_changer *ch, u_int trans, u_int src,
         cmd[8]  = (dest2 >> 8) & 0xff;
         cmd[9]  =  dest2       & 0xff;
         cmd[10] = (rotate1 ? 1 : 0) | (rotate2 ? 2 : 0);
-        
+
         return ch_do_scsi(ch, cmd, NULL,0, DMA_NONE);
 }
 
@@ -539,14 +508,14 @@ ch_set_voltag(scsi_changer *ch, u_int elem,
                 elem, tag);
         memset(cmd,0,sizeof(cmd));
         cmd[0]  = SEND_VOLUME_TAG;
-        cmd[1] = (ch->device->lun << 5) | 
+        cmd[1] = (ch->device->lun << 5) |
                 ch_elem_to_typecode(ch,elem);
         cmd[2] = (elem >> 8) & 0xff;
         cmd[3] = elem        & 0xff;
         cmd[5] = clear
                 ? (alternate ? 0x0d : 0x0c)
                 : (alternate ? 0x0b : 0x0a);
-        
+
         cmd[9] = 255;
 
         memcpy(buffer,tag,32);
@@ -562,7 +531,7 @@ static int ch_gstatus(scsi_changer *ch, int type, unsigned char __user *dest)
         int retval = 0;
         u_char data[16];
         unsigned int i;
-        
+
         mutex_lock(&ch->lock);
         for (i = 0; i < ch->counts[type]; i++) {
                 if (0 != ch_read_element_status
@@ -599,20 +568,17 @@ ch_release(struct inode *inode, struct file *file)
 static int
 ch_open(struct inode *inode, struct file *file)
 {
-        scsi_changer *tmp, *ch;
+        scsi_changer *ch;
         int minor = iminor(inode);
 
-        spin_lock(&ch_devlist_lock);
-        ch = NULL;
-        list_for_each_entry(tmp,&ch_devlist,list) {
-                if (tmp->minor == minor)
-                        ch = tmp;
-        }
+        spin_lock(&ch_index_lock);
+        ch = idr_find(&ch_index_idr, minor);
+
         if (NULL == ch || scsi_device_get(ch->device)) {
-                spin_unlock(&ch_devlist_lock);
+                spin_unlock(&ch_index_lock);
                 return -ENXIO;
         }
-        spin_unlock(&ch_devlist_lock);
+        spin_unlock(&ch_index_lock);
 
         file->private_data = ch;
         return 0;
@@ -626,24 +592,24 @@ ch_checkrange(scsi_changer *ch, unsigned int type, unsigned int unit)
         return 0;
 }
 
-static int ch_ioctl(struct inode * inode, struct file * file,
+static long ch_ioctl(struct file *file,
                     unsigned int cmd, unsigned long arg)
 {
         scsi_changer *ch = file->private_data;
         int retval;
         void __user *argp = (void __user *)arg;
-        
+
         switch (cmd) {
         case CHIOGPARAMS:
         {
                 struct changer_params params;
-                
+
                 params.cp_curpicker = 0;
                 params.cp_npickers  = ch->counts[CHET_MT];
                 params.cp_nslots    = ch->counts[CHET_ST];
                 params.cp_nportals  = ch->counts[CHET_IE];
                 params.cp_ndrives   = ch->counts[CHET_DT];
-                
+
                 if (copy_to_user(argp, &params, sizeof(params)))
                         return -EFAULT;
                 return 0;
@@ -673,11 +639,11 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                         return -EFAULT;
                 return 0;
         }
-        
+
         case CHIOPOSITION:
         {
                 struct changer_position pos;
-                
+
                 if (copy_from_user(&pos, argp, sizeof (pos)))
                         return -EFAULT;
 
@@ -692,7 +658,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                 mutex_unlock(&ch->lock);
                 return retval;
         }
-        
+
         case CHIOMOVE:
         {
                 struct changer_move mv;
@@ -705,7 +671,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                         dprintk("CHIOMOVE: invalid parameter\n");
                         return -EBADSLT;
                 }
-                
+
                 mutex_lock(&ch->lock);
                 retval = ch_move(ch,0,
                                  ch->firsts[mv.cm_fromtype] + mv.cm_fromunit,
@@ -718,7 +684,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
         case CHIOEXCHANGE:
         {
                 struct changer_exchange mv;
-                
+
                 if (copy_from_user(&mv, argp, sizeof (mv)))
                         return -EFAULT;
 
@@ -728,7 +694,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                         dprintk("CHIOEXCHANGE: invalid parameter\n");
                         return -EBADSLT;
                 }
-                
+
                 mutex_lock(&ch->lock);
                 retval = ch_exchange
                         (ch,0,
@@ -743,7 +709,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
         case CHIOGSTATUS:
         {
                 struct changer_element_status ces;
-                
+
                 if (copy_from_user(&ces, argp, sizeof (ces)))
                         return -EFAULT;
                 if (ces.ces_type < 0 || ces.ces_type >= CH_TYPES)
@@ -759,19 +725,19 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                 u_char  *buffer;
                 unsigned int elem;
                 int     result,i;
-                
+
                 if (copy_from_user(&cge, argp, sizeof (cge)))
                         return -EFAULT;
 
                 if (0 != ch_checkrange(ch, cge.cge_type, cge.cge_unit))
                         return -EINVAL;
                 elem = ch->firsts[cge.cge_type] + cge.cge_unit;
-                
+
                 buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
                 if (!buffer)
                         return -ENOMEM;
                 mutex_lock(&ch->lock);
-                
+
         voltag_retry:
                 memset(cmd,0,sizeof(cmd));
                 cmd[0] = READ_ELEMENT_STATUS;
@@ -782,7 +748,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                 cmd[3] = elem        & 0xff;
                 cmd[5] = 1;
                 cmd[9] = 255;
-                
+
                 if (0 == (result = ch_do_scsi(ch, cmd, buffer, 256, DMA_FROM_DEVICE))) {
                         cge.cge_status = buffer[18];
                         cge.cge_flags = 0;
@@ -822,7 +788,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                 }
                 kfree(buffer);
                 mutex_unlock(&ch->lock);
-                
+
                 if (copy_to_user(argp, &cge, sizeof (cge)))
                         return -EFAULT;
                 return result;
@@ -835,7 +801,7 @@ static int ch_ioctl(struct inode * inode, struct file * file,
                 mutex_unlock(&ch->lock);
                 return retval;
         }
-                
+
         case CHIOSVOLTAG:
         {
                 struct changer_set_voltag csv;
@@ -876,7 +842,7 @@ static long ch_ioctl_compat(struct file * file,
                             unsigned int cmd, unsigned long arg)
 {
         scsi_changer *ch = file->private_data;
-        
+
         switch (cmd) {
         case CHIOGPARAMS:
         case CHIOGVPARAMS:
@@ -887,13 +853,12 @@ static long ch_ioctl_compat(struct file * file,
         case CHIOINITELEM:
         case CHIOSVOLTAG:
                 /* compatible */
-                return ch_ioctl(NULL /* inode, unused */,
-                                file, cmd, arg);
+                return ch_ioctl(file, cmd, arg);
         case CHIOGSTATUS32:
         {
                 struct changer_element_status32 ces32;
                 unsigned char __user *data;
-                
+
                 if (copy_from_user(&ces32, (void __user *)arg, sizeof (ces32)))
                         return -EFAULT;
                 if (ces32.ces_type < 0 || ces32.ces_type >= CH_TYPES)
@@ -915,63 +880,100 @@ static long ch_ioctl_compat(struct file * file,
 static int ch_probe(struct device *dev)
 {
         struct scsi_device *sd = to_scsi_device(dev);
+        struct class_device *class_dev;
+        int minor, ret = -ENOMEM;
         scsi_changer *ch;
-        
+
         if (sd->type != TYPE_MEDIUM_CHANGER)
                 return -ENODEV;
-    
+
         ch = kzalloc(sizeof(*ch), GFP_KERNEL);
         if (NULL == ch)
                 return -ENOMEM;
 
-        ch->minor = ch_devcount;
+        if (!idr_pre_get(&ch_index_idr, GFP_KERNEL))
+                goto free_ch;
+
+        spin_lock(&ch_index_lock);
+        ret = idr_get_new(&ch_index_idr, ch, &minor);
+        spin_unlock(&ch_index_lock);
+
+        if (ret)
+                goto free_ch;
+
+        if (minor > CH_MAX_DEVS) {
+                ret = -ENODEV;
+                goto remove_idr;
+        }
+
+        ch->minor = minor;
         sprintf(ch->name,"ch%d",ch->minor);
+
+        class_dev = class_device_create(ch_sysfs_class, NULL,
+                                        MKDEV(SCSI_CHANGER_MAJOR, ch->minor),
+                                        dev, "s%s", ch->name);
+        if (IS_ERR(class_dev)) {
+                printk(KERN_WARNING "ch%d: class_device_create failed\n",
+                       ch->minor);
+                ret = PTR_ERR(class_dev);
+                goto remove_idr;
+        }
+
         mutex_init(&ch->lock);
         ch->device = sd;
         ch_readconfig(ch);
         if (init)
                 ch_init_elem(ch);
 
-        class_device_create(ch_sysfs_class, NULL,
-                            MKDEV(SCSI_CHANGER_MAJOR,ch->minor),
-                            dev, "s%s", ch->name);
-
+        dev_set_drvdata(dev, ch);
         sdev_printk(KERN_INFO, sd, "Attached scsi changer %s\n", ch->name);
-        
-        spin_lock(&ch_devlist_lock);
-        list_add_tail(&ch->list,&ch_devlist);
-        ch_devcount++;
-        spin_unlock(&ch_devlist_lock);
+
         return 0;
+remove_idr:
+        idr_remove(&ch_index_idr, minor);
+free_ch:
+        kfree(ch);
+        return ret;
 }
 
 static int ch_remove(struct device *dev)
 {
-        struct scsi_device *sd = to_scsi_device(dev);
-        scsi_changer *tmp, *ch;
+        scsi_changer *ch = dev_get_drvdata(dev);
 
-        spin_lock(&ch_devlist_lock);
-        ch = NULL;
-        list_for_each_entry(tmp,&ch_devlist,list) {
-                if (tmp->device == sd)
-                        ch = tmp;
-        }
-        BUG_ON(NULL == ch);
-        list_del(&ch->list);
-        spin_unlock(&ch_devlist_lock);
+        spin_lock(&ch_index_lock);
+        idr_remove(&ch_index_idr, ch->minor);
+        spin_unlock(&ch_index_lock);
 
         class_device_destroy(ch_sysfs_class,
                              MKDEV(SCSI_CHANGER_MAJOR,ch->minor));
         kfree(ch->dt);
         kfree(ch);
-        ch_devcount--;
         return 0;
 }
 
+static struct scsi_driver ch_template = {
+        .owner          = THIS_MODULE,
+        .gendrv         = {
+                .name   = "ch",
+                .probe  = ch_probe,
+                .remove = ch_remove,
+        },
+};
+
+static const struct file_operations changer_fops = {
+        .owner          = THIS_MODULE,
+        .open           = ch_open,
+        .release        = ch_release,
+        .unlocked_ioctl = ch_ioctl,
+#ifdef CONFIG_COMPAT
+        .compat_ioctl   = ch_ioctl_compat,
+#endif
+};
+
 static int __init init_ch_module(void)
 {
         int rc;
-        
+
         printk(KERN_INFO "SCSI Media Changer driver v" VERSION " \n");
         ch_sysfs_class = class_create(THIS_MODULE, "scsi_changer");
         if (IS_ERR(ch_sysfs_class)) {
@@ -996,11 +998,12 @@ static int __init init_ch_module(void)
         return rc;
 }
 
-static void __exit exit_ch_module(void) 
+static void __exit exit_ch_module(void)
 {
         scsi_unregister_driver(&ch_template.gendrv);
         unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
         class_destroy(ch_sysfs_class);
+        idr_destroy(&ch_index_idr);
 }
 
 module_init(init_ch_module);