TTY: move allocations to tty_alloc_driver

So now, that we have flags and know everything needed, keep a promise
and move all the tables and ports allocation from tty_register_driver
to tty_alloc_driver.

Not only that it makes sense, but we need this for
tty_port_link_device which needs tty_driver->ports but is to be called
before tty_register_driver.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 33 insertions, 40 deletions

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 098a7c72b640..a67609b9f21b 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -3074,6 +3074,7 @@ struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
                 unsigned long flags)
 {
         struct tty_driver *driver;
+        int err;
 
         if (!lines)
                 return ERR_PTR(-EINVAL);
@@ -3087,9 +3088,34 @@ struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
         driver->num = lines;
         driver->owner = owner;
         driver->flags = flags;
-        /* later we'll move allocation of tables here */
+
+        if (!(flags & TTY_DRIVER_DEVPTS_MEM)) {
+                driver->ttys = kcalloc(lines, sizeof(*driver->ttys),
+                                GFP_KERNEL);
+                driver->termios = kcalloc(lines, sizeof(*driver->termios),
+                                GFP_KERNEL);
+                if (!driver->ttys || !driver->termios) {
+                        err = -ENOMEM;
+                        goto err_free_all;
+                }
+        }
+
+        if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
+                driver->ports = kcalloc(lines, sizeof(*driver->ports),
+                                GFP_KERNEL);
+                if (!driver->ports) {
+                        err = -ENOMEM;
+                        goto err_free_all;
+                }
+        }
 
         return driver;
+err_free_all:
+        kfree(driver->ports);
+        kfree(driver->ttys);
+        kfree(driver->termios);
+        kfree(driver);
+        return ERR_PTR(err);
 }
 EXPORT_SYMBOL(__tty_alloc_driver);
 
@@ -3098,7 +3124,6 @@ static void destruct_tty_driver(struct kref *kref)
         struct tty_driver *driver = container_of(kref, struct tty_driver, kref);
         int i;
         struct ktermios *tp;
-        void *p;
 
         if (driver->flags & TTY_DRIVER_INSTALLED) {
                 /*
@@ -3115,14 +3140,12 @@ static void destruct_tty_driver(struct kref *kref)
                         if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV))
                                 tty_unregister_device(driver, i);
                 }
-                p = driver->ttys;
                 proc_tty_unregister_driver(driver);
-                driver->ttys = NULL;
-                driver->termios = NULL;
-                kfree(p);
                 cdev_del(&driver->cdev);
         }
         kfree(driver->ports);
+        kfree(driver->termios);
+        kfree(driver->ttys);
         kfree(driver);
 }
 
@@ -3153,27 +3176,8 @@ int tty_register_driver(struct tty_driver *driver)
         int error;
         int i;
         dev_t dev;
-        void **p = NULL;
         struct device *d;
 
-        if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
-                p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL);
-                if (!p)
-                        return -ENOMEM;
-        }
-        /*
-         * There is too many lines in PTY and we won't need the array there
-         * since it has an ->install hook where it assigns ports properly.
-         */
-        if (driver->type != TTY_DRIVER_TYPE_PTY) {
-                driver->ports = kcalloc(driver->num, sizeof(struct tty_port *),
-                                GFP_KERNEL);
-                if (!driver->ports) {
-                        error = -ENOMEM;
-                        goto err_free_p;
-                }
-        }
-
         if (!driver->major) {
                 error = alloc_chrdev_region(&dev, driver->minor_start,
                                                 driver->num, driver->name);
@@ -3186,15 +3190,7 @@ int tty_register_driver(struct tty_driver *driver)
                 error = register_chrdev_region(dev, driver->num, driver->name);
         }
         if (error < 0)
-                goto err_free_p;
-
-        if (p) {
-                driver->ttys = (struct tty_struct **)p;
-                driver->termios = (struct ktermios **)(p + driver->num);
-        } else {
-                driver->ttys = NULL;
-                driver->termios = NULL;
-        }
+                goto err;
 
         cdev_init(&driver->cdev, &tty_fops);
         driver->cdev.owner = driver->owner;
@@ -3211,7 +3207,7 @@ int tty_register_driver(struct tty_driver *driver)
                         d = tty_register_device(driver, i, NULL);
                         if (IS_ERR(d)) {
                                 error = PTR_ERR(d);
-                                goto err;
+                                goto err_unreg_devs;
                         }
                 }
         }
@@ -3219,7 +3215,7 @@ int tty_register_driver(struct tty_driver *driver)
         driver->flags |= TTY_DRIVER_INSTALLED;
         return 0;
 
-err:
+err_unreg_devs:
         for (i--; i >= 0; i--)
                 tty_unregister_device(driver, i);
 
@@ -3229,10 +3225,7 @@ err:
 
 err_unreg_char:
         unregister_chrdev_region(dev, driver->num);
-        driver->ttys = NULL;
-        driver->termios = NULL;
-err_free_p: /* destruct_tty_driver will free driver->ports */
-        kfree(p);
+err:
         return error;
 }
 EXPORT_SYMBOL(tty_register_driver);