linux-next: manual merge of the tty tree with the tty.current tree

From: Stephen Rothwell
Date: Sun Feb 07 2016 - 21:16:53 EST


Hi Greg,

Today's linux-next merge of the tty tree got a conflict in:

drivers/tty/tty_io.c

between commit:

e9036d066236 ("tty: Drop krefs for interrupted tty lock")

from the tty.current tree and commit:

d6203d0c7b73 ("tty: Refactor tty_open()")

from the tty tree.

I fixed it up (I think - see below) and can carry the fix as necessary
(no action is required).

--
Cheers,
Stephen Rothwell

diff --cc drivers/tty/tty_io.c
index a7eacef1bd22,8d26ed79bb4c..000000000000
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@@ -2004,6 -2009,69 +2009,68 @@@ static struct tty_driver *tty_lookup_dr
}

/**
+ * tty_open_by_driver - open a tty device
+ * @device: dev_t of device to open
+ * @inode: inode of device file
+ * @filp: file pointer to tty
+ *
+ * Performs the driver lookup, checks for a reopen, or otherwise
+ * performs the first-time tty initialization.
+ *
+ * Returns the locked initialized or re-opened &tty_struct
+ *
+ * Claims the global tty_mutex to serialize:
+ * - concurrent first-time tty initialization
+ * - concurrent tty driver removal w/ lookup
+ * - concurrent tty removal from driver table
+ */
+ static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,
+ struct file *filp)
+ {
+ struct tty_struct *tty;
+ struct tty_driver *driver = NULL;
+ int index = -1;
+ int retval;
+
+ mutex_lock(&tty_mutex);
+ driver = tty_lookup_driver(device, filp, &index);
+ if (IS_ERR(driver)) {
+ mutex_unlock(&tty_mutex);
+ return ERR_CAST(driver);
+ }
+
+ /* check whether we're reopening an existing tty */
+ tty = tty_driver_lookup_tty(driver, inode, index);
+ if (IS_ERR(tty)) {
+ mutex_unlock(&tty_mutex);
+ goto out;
+ }
+
+ if (tty) {
+ mutex_unlock(&tty_mutex);
+ retval = tty_lock_interruptible(tty);
++ tty_kref_put(tty); /* drop kref from tty_driver_lookup_tty() */
+ if (retval) {
+ if (retval == -EINTR)
+ retval = -ERESTARTSYS;
+ tty = ERR_PTR(retval);
+ goto out;
+ }
- /* safe to drop the kref from tty_driver_lookup_tty() */
- tty_kref_put(tty);
+ retval = tty_reopen(tty);
+ if (retval < 0) {
+ tty_unlock(tty);
+ tty = ERR_PTR(retval);
+ }
+ } else { /* Returns with the tty_lock held for now */
+ tty = tty_init_dev(driver, index);
+ mutex_unlock(&tty_mutex);
+ }
+ out:
+ tty_driver_kref_put(driver);
+ return tty;
+ }
+
+ /**
* tty_open - open a tty device
* @inode: inode of device file
* @filp: file pointer to tty