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authorDavid Brown <davidb@codeaurora.org>2011-03-16 22:13:16 -0700
committerDavid Brown <davidb@codeaurora.org>2011-03-16 22:13:16 -0700
commit92c260f755c42337c550d8ac1f8ccd1b32bffb20 (patch)
tree6d04fefc1adeecabfb2b00c201e0db78fa2b5529 /drivers/tty/n_hdlc.c
parent8e76a80960bf06c245160a484d5a363ca6b520bb (diff)
parent05e34754518b6a90d5c392790c032575fab12d66 (diff)
downloadtalos-obmc-linux-92c260f755c42337c550d8ac1f8ccd1b32bffb20.tar.gz
talos-obmc-linux-92c260f755c42337c550d8ac1f8ccd1b32bffb20.zip
Merge remote branch 'rmk/for-linus' into for-linus
* rmk/for-linus: (1557 commits) ARM: 6806/1: irq: introduce entry and exit functions for chained handlers ARM: 6781/1: Thumb-2: Work around buggy Thumb-2 short branch relocations in gas ARM: 6747/1: P2V: Thumb2 support ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump ARM: 6796/1: Footbridge: Fix I/O mappings for NOMMU mode ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9 ARM: 6772/1: errata: possible fault MMU translations following an ASID switch ARM: 6776/1: mach-ux500: activate fix for errata 753970 ARM: 6794/1: SPEAr: Append UL to device address macros. ARM: 6793/1: SPEAr: Remove unused *_SIZE macros from spear*.h files ARM: 6792/1: SPEAr: Replace SIZE macro's with SZ_4K macros ARM: 6791/1: SPEAr3xx: Declare device structures after shirq code ARM: 6790/1: SPEAr: Clock Framework: Rename usbd clock and align apb_clk entry ARM: 6789/1: SPEAr3xx: Rename sdio to sdhci ARM: 6788/1: SPEAr: Include mach/hardware.h instead of mach/spear.h ARM: 6787/1: SPEAr: Reorder #includes in .h & .c files. ARM: 6681/1: SPEAr: add debugfs support to clk API ARM: 6703/1: SPEAr: update clk API support ARM: 6679/1: SPEAr: make clk API functions more generic ARM: 6737/1: SPEAr: formalized timer support ... Conflicts: arch/arm/mach-msm/board-msm7x27.c arch/arm/mach-msm/board-msm7x30.c arch/arm/mach-msm/board-qsd8x50.c arch/arm/mach-msm/board-sapphire.c arch/arm/mach-msm/include/mach/memory.h
Diffstat (limited to 'drivers/tty/n_hdlc.c')
-rw-r--r--drivers/tty/n_hdlc.c90
1 files changed, 45 insertions, 45 deletions
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 47d32281032c..52fc0c9a6364 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -581,8 +581,9 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
__u8 __user *buf, size_t nr)
{
struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
- int ret;
+ int ret = 0;
struct n_hdlc_buf *rbuf;
+ DECLARE_WAITQUEUE(wait, current);
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__);
@@ -598,57 +599,55 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
return -EFAULT;
}
- tty_lock();
+ add_wait_queue(&tty->read_wait, &wait);
for (;;) {
if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
- tty_unlock();
- return -EIO;
+ ret = -EIO;
+ break;
}
+ if (tty_hung_up_p(file))
+ break;
- n_hdlc = tty2n_hdlc (tty);
- if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC ||
- tty != n_hdlc->tty) {
- tty_unlock();
- return 0;
- }
+ set_current_state(TASK_INTERRUPTIBLE);
rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
- if (rbuf)
+ if (rbuf) {
+ if (rbuf->count > nr) {
+ /* too large for caller's buffer */
+ ret = -EOVERFLOW;
+ } else {
+ if (copy_to_user(buf, rbuf->buf, rbuf->count))
+ ret = -EFAULT;
+ else
+ ret = rbuf->count;
+ }
+
+ if (n_hdlc->rx_free_buf_list.count >
+ DEFAULT_RX_BUF_COUNT)
+ kfree(rbuf);
+ else
+ n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
break;
+ }
/* no data */
if (file->f_flags & O_NONBLOCK) {
- tty_unlock();
- return -EAGAIN;
+ ret = -EAGAIN;
+ break;
}
-
- interruptible_sleep_on (&tty->read_wait);
+
+ schedule();
+
if (signal_pending(current)) {
- tty_unlock();
- return -EINTR;
+ ret = -EINTR;
+ break;
}
}
-
- if (rbuf->count > nr)
- /* frame too large for caller's buffer (discard frame) */
- ret = -EOVERFLOW;
- else {
- /* Copy the data to the caller's buffer */
- if (copy_to_user(buf, rbuf->buf, rbuf->count))
- ret = -EFAULT;
- else
- ret = rbuf->count;
- }
-
- /* return HDLC buffer to free list unless the free list */
- /* count has exceeded the default value, in which case the */
- /* buffer is freed back to the OS to conserve memory */
- if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT)
- kfree(rbuf);
- else
- n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf);
- tty_unlock();
+
+ remove_wait_queue(&tty->read_wait, &wait);
+ __set_current_state(TASK_RUNNING);
+
return ret;
} /* end of n_hdlc_tty_read() */
@@ -691,14 +690,15 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
count = maxframe;
}
- tty_lock();
-
add_wait_queue(&tty->write_wait, &wait);
- set_current_state(TASK_INTERRUPTIBLE);
+
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
- /* Allocate transmit buffer */
- /* sleep until transmit buffer available */
- while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) {
+ tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list);
+ if (tbuf)
+ break;
+
if (file->f_flags & O_NONBLOCK) {
error = -EAGAIN;
break;
@@ -719,7 +719,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
}
}
- set_current_state(TASK_RUNNING);
+ __set_current_state(TASK_RUNNING);
remove_wait_queue(&tty->write_wait, &wait);
if (!error) {
@@ -731,7 +731,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf);
n_hdlc_send_frames(n_hdlc,tty);
}
- tty_unlock();
+
return error;
} /* end of n_hdlc_tty_write() */
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