Dynamic device minor support. Minor device numbers will be reused if the

    device is hotplugged in/out of the system

1 files changed, 236 insertions, 155 deletions

diff --git a/linux/drm_stub.h b/linux/drm_stub.h
index 3d9ade35..8fd690d9 100644
--- a/linux/drm_stub.h
+++ b/linux/drm_stub.h
@@ -33,14 +33,18 @@
 
 #include "drmP.h"
 
-#define DRM_STUB_MAXCARDS 16	/* Enough for one machine */
+static unsigned int cards_limit = 16;	/* Enough for one machine */
+static unsigned int debug = 0;		/* 1 to enable debug output */
 
-/** Stub list. One for each minor. */
-static struct drm_stub_list {
-	const char             *name;
-	struct file_operations *fops;	/**< file operations */
-	struct proc_dir_entry  *dev_root;	/**< proc directory entry */
-} *DRM(stub_list);
+MODULE_AUTHOR( DRIVER_AUTHOR );
+MODULE_DESCRIPTION( DRIVER_DESC );
+MODULE_LICENSE("GPL and additional rights");
+module_param(cards_limit, int, 0444);
+MODULE_PARM_DESC(cards_limit, "Maximum number of graphics cards");
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "Enable debug output");
+
+drm_global_t *DRM(global);
 
 /**
  * File \c open operation.
@@ -51,15 +55,24 @@ static struct drm_stub_list {
  * Puts the drm_stub_list::fops corresponding to the device minor number into
  * \p filp, call the \c open method, and restore the file operations.
  */
-static int DRM(stub_open)(struct inode *inode, struct file *filp)
+static int stub_open(struct inode *inode, struct file *filp)
 {
-	int                    minor = iminor(inode);
-	int                    err   = -ENODEV;
+	drm_device_t *dev = NULL;
+	int minor = iminor(inode);
+	int err = -ENODEV;
 	struct file_operations *old_fops;
+	
+	DRM_DEBUG("\n");
+
+	if (!((minor >= 0) && (minor < DRM(global)->cards_limit)))
+		return -ENODEV;
 
-	if (!DRM(stub_list) || !DRM(stub_list)[minor].fops) return -ENODEV;
-	old_fops   = filp->f_op;
-	filp->f_op = fops_get(DRM(stub_list)[minor].fops);
+	dev = DRM(global)->minors[minor].dev;
+	if (!dev)
+		return -ENODEV;
+
+	old_fops = filp->f_op;
+	filp->f_op = fops_get(dev->fops);
 	if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 		fops_put(filp->f_op);
 		filp->f_op = fops_get(old_fops);
@@ -72,23 +85,24 @@ static int DRM(stub_open)(struct inode *inode, struct file *filp)
 /** File operations structure */
 static struct file_operations DRM(stub_fops) = {
 	.owner = THIS_MODULE,
-	.open  = DRM(stub_open)
+	.open  = stub_open
 };
 
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,0)
-static int drm_hotplug (struct class_device *dev, char **envp, int num_envp,
+static int drm_hotplug (struct class_device *cdev, char **envp, int num_envp,
 				char *buffer, int buffer_size)
 {
+	drm_device_t *dev;
 	struct pci_dev *pdev;
 	char *scratch;
 	int i = 0;
 	int length = 0;
-	
+
 	DRM_DEBUG("\n");
-	if (!dev)
+	if (!cdev)
 		return -ENODEV;
 
-	pdev = to_pci_dev(dev->dev);
+	pdev = to_pci_dev(cdev->dev);
 	if (!pdev)
 		return -ENODEV;
 
@@ -127,19 +141,17 @@ static int drm_hotplug (struct class_device *dev, char **envp, int num_envp,
 		return -ENOMEM;
 	++length;
 	scratch += length;
-#if 0	
-	drm_device_t *ddev;
-	ddev = pci_get_drvdata(pdev);
-	if (ddev) {
+
+	dev = pci_get_drvdata(pdev);
+	if (dev) {
 		envp[i++] = scratch;
 		length += snprintf (scratch, buffer_size - length, 
-							"RESET=%s", (ddev->need_reset ? "true" : "false"));
+							"RESET=%s", (dev->need_reset ? "true" : "false"));
 		if ((buffer_size - length <= 0) || (i >= num_envp))
 			return -ENOMEM;
 	}
-#endif	
 	envp[i] = 0;
-	
+
 	return 0;
 }
 #endif
@@ -156,33 +168,105 @@ static int drm_hotplug (struct class_device *dev, char **envp, int num_envp,
  * empty entry and initialize it to the given parameters, and create the proc
  * init entry via proc_init().
  */
-static int DRM(stub_getminor)(const char *name, struct file_operations *fops,
-			      drm_device_t *dev)
+static int get_minor(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
-	int i;
+	struct class_device *dev_class;
+	drm_device_t *dev;
+	int ret;
+	int minor;
+	drm_minor_t *minors = &DRM(global)->minors[0];
 
-	if (!DRM(stub_list)) {
-		DRM(stub_list) = DRM(alloc)(sizeof(*DRM(stub_list))
-					    * DRM_STUB_MAXCARDS, DRM_MEM_STUB);
-		if(!DRM(stub_list)) return -1;
-		for (i = 0; i < DRM_STUB_MAXCARDS; i++) {
-			DRM(stub_list)[i].name = NULL;
-			DRM(stub_list)[i].fops = NULL;
+	DRM_DEBUG("\n");
+
+	for (minor = 0; minor < DRM(global)->cards_limit; minor++, minors++) {
+		if (minors->class == DRM_MINOR_FREE) {
+
+			DRM_DEBUG("assigning minor %d\n", minor);
+			dev = DRM(calloc)(1, sizeof(*dev), DRM_MEM_STUB);
+			if(!dev) 
+				return -ENOMEM;
+
+			*minors = (drm_minor_t){.dev = NULL, .class = DRM_MINOR_PRIMARY};
+			dev->minor = minor;
+			if ((ret = DRM(fill_in_dev)(dev, pdev, ent))) {
+				printk (KERN_ERR "DRM: Fill_in_dev failed.\n");
+				goto err_g1;
+			}
+			if ((ret = DRM(proc_init)(dev, minor, DRM(global)->proc_root, &minors->dev_root))) {
+				printk (KERN_ERR "DRM: Failed to initialize /proc/dri.\n");
+				goto err_g1;
+			}
+			if (!DRM(fb_loaded)) {	/* set this before device_add hotplug uses it */
+				pci_set_drvdata(pdev, dev);
+				pci_request_regions(pdev, DRIVER_NAME);
+				pci_enable_device(pdev);
+			}
+			dev_class = class_simple_device_add(DRM(global)->drm_class, 
+					MKDEV(DRM_MAJOR, minor), &pdev->dev, "card%d", minor);
+			if (IS_ERR(dev_class)) {
+				printk (KERN_ERR "DRM: Error class_simple_device_add.\n");
+				ret = PTR_ERR(dev_class);
+				goto err_g2;
+			}
+
+			DRM_DEBUG("new primary minor assigned %d\n", minor);
+			return 0;
 		}
 	}
-	for (i = 0; i < DRM_STUB_MAXCARDS; i++) {
-		if (!DRM(stub_list)[i].fops) {
-			DRM(stub_list)[i].name = name;
-			DRM(stub_list)[i].fops = fops;
-			DRM(proc_init)(dev, i, DRM(stub_info).proc_root,
-							&DRM(stub_list)[i].dev_root);
-			(*DRM(stub_info).info_count)++;
-			DRM_DEBUG("info count increased %d\n", *DRM(stub_info).info_count);
-			
-			return i;
+	DRM_ERROR("out of minors\n");
+	return -ENOMEM;
+err_g2:
+	if (!DRM(fb_loaded)) {
+		pci_set_drvdata(pdev, NULL);
+		pci_release_regions(pdev);
+		pci_disable_device(pdev);
+	}
+	DRM(proc_cleanup)(minor, DRM(global)->proc_root, minors->dev_root);
+err_g1:
+	*minors = (drm_minor_t){.dev = NULL, .class = DRM_MINOR_FREE};
+	DRM(free)(dev, sizeof(*dev), DRM_MEM_STUB);
+	return ret;
+}
+
+int DRM(get_secondary_minor)(drm_device_t *dev, drm_minor_t **sec_minor)
+{
+	drm_minor_t *minors = &DRM(global)->minors[0];
+	struct class_device *dev_class;
+	int ret;
+	int minor;
+
+	DRM_DEBUG("\n");
+
+	for (minor = 0; minor < DRM(global)->cards_limit; minor++, minors++) {
+		if (minors->class == DRM_MINOR_FREE) {
+
+			*minors = (drm_minor_t){.dev = dev, .class = DRM_MINOR_SECONDARY};
+			if ((ret = DRM(proc_init)(dev, minor, DRM(global)->proc_root, &minors->dev_root))) {
+				printk (KERN_ERR "DRM: Failed to initialize /proc/dri.\n");
+				goto err_g1;
+			}
+
+			dev_class = class_simple_device_add(DRM(global)->drm_class, 
+					MKDEV(DRM_MAJOR, minor), &dev->pdev->dev, "card%d", minor);
+			if (IS_ERR(dev_class)) {
+				printk (KERN_ERR "DRM: Error class_simple_device_add.\n");
+				ret = PTR_ERR(dev_class);
+				goto err_g2;
+			}
+			*sec_minor = minors;
+
+			DRM_DEBUG("new secondary minor assigned %d\n", minor);
+			return 0;
 		}
 	}
-	return -1;
+	DRM_ERROR("out of minors\n");
+	return -ENOMEM;
+err_g2:
+	DRM(proc_cleanup)(minor, DRM(global)->proc_root, minors->dev_root);
+err_g1:
+	*minors = (drm_minor_t){.dev = NULL, .class = DRM_MINOR_FREE};
+	DRM(free)(dev, sizeof(*dev), DRM_MEM_STUB);
+	return ret;
 }
 
 /**
@@ -195,31 +279,53 @@ static int DRM(stub_getminor)(const char *name, struct file_operations *fops,
  * "drm" data, otherwise unregisters the "drm" data, frees the stub list and
  * unregisters the character device. 
  */
-static int DRM(stub_putminor)(int minor)
+int DRM(put_minor)(drm_device_t *dev)
 {
-	if (minor < 0 || minor >= DRM_STUB_MAXCARDS) return -1;
-	DRM(stub_list)[minor].name = NULL;
-	DRM(stub_list)[minor].fops = NULL;
-	DRM(proc_cleanup)(minor, DRM(stub_info).proc_root,
-			  DRM(stub_list)[minor].dev_root);
+	drm_minor_t *minors = &DRM(global)->minors[dev->minor];
+	int i;
+	
+	DRM_DEBUG("release primary minor %d\n", dev->minor);
 
-	(*DRM(stub_info).info_count)--;
+	DRM(proc_cleanup)(dev->minor, DRM(global)->proc_root, minors->dev_root);
+	class_simple_device_remove(MKDEV(DRM_MAJOR, dev->minor));
 
-	if ((*DRM(stub_info).info_count) != 0) {
-		if (DRM(numdevs) == 0) {
-			DRM_DEBUG("inter_module_put called %d\n", *DRM(stub_info).info_count);
+	*minors = (drm_minor_t){.dev = NULL, .class = DRM_MINOR_FREE};
+	DRM(free)(dev, sizeof(*dev), DRM_MEM_STUB);
+
+	/* if any device pointers are non-NULL we are not the last module */
+	for (i = 0; i < DRM(global)->cards_limit; i++) {
+		if (DRM(global)->minors[i].class != DRM_MINOR_FREE) {
+			DRM_DEBUG("inter_module_put called\n");
 			inter_module_put("drm");
+			return 0;
 		}
-	} else {
-		DRM_DEBUG("unregistering inter_module \n");
-		inter_module_unregister("drm");
-		DRM(free)(DRM(stub_list),
-			  sizeof(*DRM(stub_list)) * DRM_STUB_MAXCARDS,
-			  DRM_MEM_STUB);
-		remove_proc_entry("dri", NULL);
-		class_simple_destroy(DRM(stub_info).drm_class);
-		unregister_chrdev(DRM_MAJOR, "drm");
 	}
+	DRM_DEBUG("unregistering inter_module \n");
+	inter_module_unregister("drm");
+	remove_proc_entry("dri", NULL);
+	class_simple_destroy(DRM(global)->drm_class);
+	cdev_del(&DRM(global)->drm_cdev);
+	unregister_chrdev_region(MKDEV(DRM_MAJOR, 0), DRM_MAX_MINOR);
+
+	DRM(free)(DRM(global)->minors, sizeof(*DRM(global)->minors) *
+				DRM(global)->cards_limit, DRM_MEM_STUB);
+	DRM(free)(DRM(global), sizeof(*DRM(global)), DRM_MEM_STUB);
+	DRM(global) = NULL;
+
+	return 0;
+}
+
+int DRM(put_secondary_minor)(drm_minor_t *sec_minor)
+{
+	int minor = sec_minor - &DRM(global)->minors[0];
+
+	DRM_DEBUG("release secondary minor %d\n", minor);
+
+	DRM(proc_cleanup)(minor, DRM(global)->proc_root, sec_minor->dev_root);
+	class_simple_device_remove(MKDEV(DRM_MAJOR, minor));
+
+	*sec_minor = (drm_minor_t){.dev = NULL, .class = DRM_MINOR_FREE};
+
 	return 0;
 }
 
@@ -237,104 +343,79 @@ static int DRM(stub_putminor)(int minor)
  *
  * Finally calls stub_info::info_register.
  */
-int DRM(stub_register)(const char *name, struct file_operations *fops,
-		       drm_device_t *dev)
+int DRM(probe)(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
-	struct drm_stub_info *i = NULL;
-	int ret1;
-	int ret2;
+	dev_t dev = MKDEV(DRM_MAJOR, 0);
+	drm_global_t *global;
+	int ret = -ENOMEM;
 
 	DRM_DEBUG("\n");
 
-	/* if we are registering a second device we don't need to worry
-	   about inter module get/put and other things as they've been
-	   done already */
-	if (DRM(numdevs) == 0) {
-		/* use the inter_module_get to check - as if the same module
-		   registers chrdev twice it succeeds */
-		i = (struct drm_stub_info *)inter_module_get("drm");
-		if (i) {
-			/* Already registered */
-			DRM(stub_info).info_register   = i->info_register;
-			DRM(stub_info).info_unregister = i->info_unregister;
-			DRM(stub_info).drm_class = i->drm_class;
-			DRM(stub_info).info_count = i->info_count;
-			DRM_DEBUG("already registered %d\n", *i->info_count);
-		} else if (*DRM(stub_info).info_count == 0) {
-
-			ret1 = register_chrdev(DRM_MAJOR, "drm", &DRM(stub_fops));
-			if (ret1 < 0) {
-				printk (KERN_ERR "Error registering drm major number.\n");
-				return ret1;
-			}
+	/* use the inter_module_get to check - as if the same module
+		registers chrdev twice it succeeds */
+	global = (drm_global_t *)inter_module_get("drm");
+	if (global) {
+		DRM(global) = global;
+		global = NULL;
+	} else {
+		DRM_DEBUG("first probe\n");
 
-			DRM(stub_info).drm_class = class_simple_create(THIS_MODULE, "drm");
-			if (IS_ERR(DRM(stub_info).drm_class)) {
-				printk (KERN_ERR "Error creating drm class.\n");
-				unregister_chrdev(DRM_MAJOR, "drm");
-				return PTR_ERR(DRM(stub_info).drm_class);
-			}
-			class_simple_set_hotplug(DRM(stub_info).drm_class, drm_hotplug);
+		global = DRM(calloc)(1, sizeof(*global), DRM_MEM_STUB);
+		if(!global) 
+			return -ENOMEM;
 
-			DRM_DEBUG("calling inter_module_register\n");
-			inter_module_register("drm", THIS_MODULE, &DRM(stub_info));
+		global->cards_limit = (cards_limit < DRM_MAX_MINOR + 1 ? cards_limit : DRM_MAX_MINOR + 1);
+		global->minors = DRM(calloc)(global->cards_limit, 
+					sizeof(*global->minors), DRM_MEM_STUB);
+		if(!global->minors) 
+			goto err_p1;
+
+		if (register_chrdev_region(dev, DRM_MAX_MINOR, "drm"))
+			goto err_p1;
+	
+		strncpy(global->drm_cdev.kobj.name, "drm", KOBJ_NAME_LEN);
+		global->drm_cdev.owner = THIS_MODULE;
+		cdev_init(&global->drm_cdev, &DRM(stub_fops));
+		if (cdev_add(&global->drm_cdev, dev, DRM_MAX_MINOR)) {
+			kobject_put(&global->drm_cdev.kobj);
+			printk (KERN_ERR "DRM: Error registering drm major number.\n");
+			goto err_p2;
+		}
 			
-			DRM(stub_info).proc_root = create_proc_entry("dri", S_IFDIR, NULL);
-			if (!DRM(stub_info).proc_root) {
-				DRM_ERROR("Cannot create /proc/dri\n");
-				inter_module_unregister("drm");
-				unregister_chrdev(DRM_MAJOR, "drm");
-				class_simple_destroy(DRM(stub_info).drm_class);
-				return -1;
-			}
-		
+		global->drm_class = class_simple_create(THIS_MODULE, "drm");
+		if (IS_ERR(global->drm_class)) {
+			printk (KERN_ERR "DRM: Error creating drm class.\n");
+			ret = PTR_ERR(global->drm_class);
+			goto err_p3;
 		}
-	} else
-		DRM_DEBUG("already retrieved inter_module information\n");
-
-	if (DRM(stub_info).info_register) {
-		ret2 = DRM(stub_info).info_register(name, fops, dev);
-		if (ret2 < 0) {
-			if (DRM(numdevs) == 0 && !i) {
-				inter_module_unregister("drm");
-				unregister_chrdev(DRM_MAJOR, "drm");
-				class_simple_destroy(DRM(stub_info).drm_class);
-				remove_proc_entry("dri", NULL);
-				DRM_DEBUG("info_register failed, deregistered everything\n");
-			}
-			DRM_DEBUG("info_register failed\n");
-			return ret2;
+		class_simple_set_hotplug(global->drm_class, drm_hotplug);
+
+		global->proc_root = create_proc_entry("dri", S_IFDIR, NULL);
+		if (!global->proc_root) {
+			DRM_ERROR("Cannot create /proc/dri\n");
+			ret = -1;
+			goto err_p4;
 		}
-		class_simple_device_add(DRM(stub_info).drm_class, 
-				MKDEV(DRM_MAJOR, ret2), &dev->pdev->dev, "card%d", ret2);
-		return ret2;
+		DRM_DEBUG("calling inter_module_register\n");
+		inter_module_register("drm", THIS_MODULE, global);
+		
+		DRM(global) = global;
 	}
-	return -1;
-}
-
-/**
- * Unregister.
- *
- * \param minor
- *
- * Calls drm_stub_info::unregister.
- */
-int DRM(stub_unregister)(int minor)
-{
-	DRM_DEBUG("%d\n", minor);
-	class_simple_device_remove(MKDEV(DRM_MAJOR, minor));
-	if (DRM(stub_info).info_unregister)
-		return DRM(stub_info).info_unregister(minor);
-	return -1;
+	if ((ret = get_minor(pdev, ent))) {
+		if (global)
+			goto err_p4;
+		return ret;
+	}
+	return 0;
+err_p4:
+	class_simple_destroy(global->drm_class);
+err_p3:
+	cdev_del(&global->drm_cdev);
+	unregister_chrdev_region(dev, DRM_MAX_MINOR);
+err_p2:
+	DRM(free)(global->minors, sizeof(*global->minors) * global->cards_limit, DRM_MEM_STUB);
+err_p1:	
+	DRM(free)(global, sizeof(*global), DRM_MEM_STUB);
+	DRM(global) = NULL;
+	return ret;
 }
-
-int DRM(stub_count);
-
-/** Stub information */
-struct drm_stub_info DRM(stub_info) = {
-	.info_register   = DRM(stub_getminor),
-	.info_unregister = DRM(stub_putminor),
-	.drm_class = NULL,
-	.info_count = &DRM(stub_count),
-	.proc_root = NULL,
-};