#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/ratelimit.h>
+#include <linux/vmalloc.h>
/* number of characters left in xmit buffer before select has we have room */
size_t canon_head;
size_t echo_head;
size_t echo_commit;
- DECLARE_BITMAP(process_char_map, 256);
+ DECLARE_BITMAP(char_map, 256);
/* private to n_tty_receive_overrun (single-threaded) */
unsigned long overrun_time;
kill_fasync(&tty->fasync, SIGIO, POLL_OUT);
}
-static inline void n_tty_check_throttle(struct tty_struct *tty)
+static void n_tty_check_throttle(struct tty_struct *tty)
{
if (tty->driver->type == TTY_DRIVER_TYPE_PTY)
return;
__tty_set_flow_change(tty, 0);
}
-static inline void n_tty_check_unthrottle(struct tty_struct *tty)
+static void n_tty_check_unthrottle(struct tty_struct *tty)
{
if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
tty->link->ldisc->ops->write_wakeup == n_tty_write_wakeup) {
* not active.
*/
-static void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
+static inline void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
{
- if (read_cnt(ldata) < N_TTY_BUF_SIZE) {
- *read_buf_addr(ldata, ldata->read_head) = c;
- ldata->read_head++;
- }
+ *read_buf_addr(ldata, ldata->read_head++) = c;
}
/**
* Locking: ctrl_lock
*/
-static inline void isig(int sig, struct tty_struct *tty)
+static void isig(int sig, struct tty_struct *tty)
{
struct pid *tty_pgrp = tty_get_pgrp(tty);
if (tty_pgrp) {
* Note: may get exclusive termios_rwsem if flushing input buffer
*/
-static inline void n_tty_receive_break(struct tty_struct *tty)
+static void n_tty_receive_break(struct tty_struct *tty)
{
struct n_tty_data *ldata = tty->disc_data;
* private.
*/
-static inline void n_tty_receive_overrun(struct tty_struct *tty)
+static void n_tty_receive_overrun(struct tty_struct *tty)
{
struct n_tty_data *ldata = tty->disc_data;
char buf[64];
* caller holds non-exclusive termios_rwsem
* publishes read_head via put_tty_queue()
*/
-static inline void n_tty_receive_parity_error(struct tty_struct *tty,
- unsigned char c)
+static void n_tty_receive_parity_error(struct tty_struct *tty, unsigned char c)
{
struct n_tty_data *ldata = tty->disc_data;
wake_up_interruptible(&tty->read_wait);
}
+static void
+n_tty_receive_signal_char(struct tty_struct *tty, int signal, unsigned char c)
+{
+ if (!L_NOFLSH(tty)) {
+ /* flushing needs exclusive termios_rwsem */
+ up_read(&tty->termios_rwsem);
+ n_tty_flush_buffer(tty);
+ tty_driver_flush_buffer(tty);
+ down_read(&tty->termios_rwsem);
+ }
+ if (I_IXON(tty))
+ start_tty(tty);
+ if (L_ECHO(tty)) {
+ echo_char(c, tty);
+ commit_echoes(tty);
+ }
+ isig(signal, tty);
+ return;
+}
+
/**
* n_tty_receive_char - perform processing
* @tty: terminal device
* caller holds non-exclusive termios_rwsem
* publishes canon_head if canonical mode is active
* otherwise, publishes read_head via put_tty_queue()
+ *
+ * Returns 1 if LNEXT was received, else returns 0
*/
-static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
+static int
+n_tty_receive_char_special(struct tty_struct *tty, unsigned char c)
{
struct n_tty_data *ldata = tty->disc_data;
int parmrk;
- if (ldata->raw) {
- put_tty_queue(c, ldata);
- return;
- }
-
- if (I_ISTRIP(tty))
- c &= 0x7f;
- if (I_IUCLC(tty) && L_IEXTEN(tty))
- c = tolower(c);
-
- if (L_EXTPROC(tty)) {
- put_tty_queue(c, ldata);
- return;
- }
-
- if (tty->stopped && !tty->flow_stopped && I_IXON(tty) &&
- I_IXANY(tty) && c != START_CHAR(tty) && c != STOP_CHAR(tty) &&
- c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) && c != SUSP_CHAR(tty)) {
- start_tty(tty);
- process_echoes(tty);
- }
-
- if (tty->closing) {
- if (I_IXON(tty)) {
- if (c == START_CHAR(tty)) {
- start_tty(tty);
- process_echoes(tty);
- } else if (c == STOP_CHAR(tty))
- stop_tty(tty);
- }
- return;
- }
-
- /*
- * If the previous character was LNEXT, or we know that this
- * character is not one of the characters that we'll have to
- * handle specially, do shortcut processing to speed things
- * up.
- */
- if (!test_bit(c, ldata->process_char_map) || ldata->lnext) {
- ldata->lnext = 0;
- parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
- if (read_cnt(ldata) >= (N_TTY_BUF_SIZE - parmrk - 1)) {
- /* beep if no space */
- if (L_ECHO(tty))
- process_output('\a', tty);
- return;
- }
- if (L_ECHO(tty)) {
- finish_erasing(ldata);
- /* Record the column of first canon char. */
- if (ldata->canon_head == ldata->read_head)
- echo_set_canon_col(ldata);
- echo_char(c, tty);
- commit_echoes(tty);
- }
- if (parmrk)
- put_tty_queue(c, ldata);
- put_tty_queue(c, ldata);
- return;
- }
-
if (I_IXON(tty)) {
if (c == START_CHAR(tty)) {
start_tty(tty);
commit_echoes(tty);
- return;
+ return 0;
}
if (c == STOP_CHAR(tty)) {
stop_tty(tty);
- return;
+ return 0;
}
}
if (L_ISIG(tty)) {
- int signal;
- signal = SIGINT;
- if (c == INTR_CHAR(tty))
- goto send_signal;
- signal = SIGQUIT;
- if (c == QUIT_CHAR(tty))
- goto send_signal;
- signal = SIGTSTP;
- if (c == SUSP_CHAR(tty)) {
-send_signal:
- if (!L_NOFLSH(tty)) {
- /* flushing needs exclusive termios_rwsem */
- up_read(&tty->termios_rwsem);
- n_tty_flush_buffer(tty);
- tty_driver_flush_buffer(tty);
- down_read(&tty->termios_rwsem);
- }
- if (I_IXON(tty))
- start_tty(tty);
- if (L_ECHO(tty)) {
- echo_char(c, tty);
- commit_echoes(tty);
- }
- isig(signal, tty);
- return;
+ if (c == INTR_CHAR(tty)) {
+ n_tty_receive_signal_char(tty, SIGINT, c);
+ return 0;
+ } else if (c == QUIT_CHAR(tty)) {
+ n_tty_receive_signal_char(tty, SIGQUIT, c);
+ return 0;
+ } else if (c == SUSP_CHAR(tty)) {
+ n_tty_receive_signal_char(tty, SIGTSTP, c);
+ return 0;
}
}
+ if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+ start_tty(tty);
+ process_echoes(tty);
+ }
+
if (c == '\r') {
if (I_IGNCR(tty))
- return;
+ return 0;
if (I_ICRNL(tty))
c = '\n';
} else if (c == '\n' && I_INLCR(tty))
(c == WERASE_CHAR(tty) && L_IEXTEN(tty))) {
eraser(c, tty);
commit_echoes(tty);
- return;
+ return 0;
}
if (c == LNEXT_CHAR(tty) && L_IEXTEN(tty)) {
ldata->lnext = 1;
commit_echoes(tty);
}
}
- return;
+ return 1;
}
- if (c == REPRINT_CHAR(tty) && L_ECHO(tty) &&
- L_IEXTEN(tty)) {
+ if (c == REPRINT_CHAR(tty) && L_ECHO(tty) && L_IEXTEN(tty)) {
size_t tail = ldata->canon_head;
finish_erasing(ldata);
tail++;
}
commit_echoes(tty);
- return;
+ return 0;
}
if (c == '\n') {
- if (read_cnt(ldata) >= N_TTY_BUF_SIZE) {
- if (L_ECHO(tty))
- process_output('\a', tty);
- return;
- }
if (L_ECHO(tty) || L_ECHONL(tty)) {
echo_char_raw('\n', ldata);
commit_echoes(tty);
goto handle_newline;
}
if (c == EOF_CHAR(tty)) {
- if (read_cnt(ldata) >= N_TTY_BUF_SIZE)
- return;
c = __DISABLED_CHAR;
goto handle_newline;
}
(c == EOL2_CHAR(tty) && L_IEXTEN(tty))) {
parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty))
? 1 : 0;
- if (read_cnt(ldata) >= (N_TTY_BUF_SIZE - parmrk)) {
- if (L_ECHO(tty))
- process_output('\a', tty);
- return;
- }
/*
* XXX are EOL_CHAR and EOL2_CHAR echoed?!?
*/
kill_fasync(&tty->fasync, SIGIO, POLL_IN);
if (waitqueue_active(&tty->read_wait))
wake_up_interruptible(&tty->read_wait);
- return;
+ return 0;
}
}
parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
- if (read_cnt(ldata) >= (N_TTY_BUF_SIZE - parmrk - 1)) {
- /* beep if no space */
- if (L_ECHO(tty))
- process_output('\a', tty);
- return;
- }
if (L_ECHO(tty)) {
finish_erasing(ldata);
if (c == '\n')
put_tty_queue(c, ldata);
put_tty_queue(c, ldata);
+ return 0;
+}
+
+static inline void
+n_tty_receive_char_inline(struct tty_struct *tty, unsigned char c)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+ int parmrk;
+
+ if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+ start_tty(tty);
+ process_echoes(tty);
+ }
+ if (L_ECHO(tty)) {
+ finish_erasing(ldata);
+ /* Record the column of first canon char. */
+ if (ldata->canon_head == ldata->read_head)
+ echo_set_canon_col(ldata);
+ echo_char(c, tty);
+ commit_echoes(tty);
+ }
+ parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
+ if (parmrk)
+ put_tty_queue(c, ldata);
+ put_tty_queue(c, ldata);
+}
+
+static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
+{
+ n_tty_receive_char_inline(tty, c);
+}
+
+static inline void
+n_tty_receive_char_fast(struct tty_struct *tty, unsigned char c)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+
+ if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+ start_tty(tty);
+ process_echoes(tty);
+ }
+ if (L_ECHO(tty)) {
+ finish_erasing(ldata);
+ /* Record the column of first canon char. */
+ if (ldata->canon_head == ldata->read_head)
+ echo_set_canon_col(ldata);
+ echo_char(c, tty);
+ commit_echoes(tty);
+ }
+ put_tty_queue(c, ldata);
+}
+
+static inline void
+n_tty_receive_char_closing(struct tty_struct *tty, unsigned char c)
+{
+ if (I_ISTRIP(tty))
+ c &= 0x7f;
+ if (I_IUCLC(tty) && L_IEXTEN(tty))
+ c = tolower(c);
+
+ if (I_IXON(tty)) {
+ if (c == STOP_CHAR(tty))
+ stop_tty(tty);
+ else if (c == START_CHAR(tty) ||
+ (tty->stopped && !tty->flow_stopped && I_IXANY(tty) &&
+ c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) &&
+ c != SUSP_CHAR(tty))) {
+ start_tty(tty);
+ process_echoes(tty);
+ }
+ }
+}
+
+static void
+n_tty_receive_char_flagged(struct tty_struct *tty, unsigned char c, char flag)
+{
+ char buf[64];
+
+ switch (flag) {
+ case TTY_BREAK:
+ n_tty_receive_break(tty);
+ break;
+ case TTY_PARITY:
+ case TTY_FRAME:
+ n_tty_receive_parity_error(tty, c);
+ break;
+ case TTY_OVERRUN:
+ n_tty_receive_overrun(tty);
+ break;
+ default:
+ printk(KERN_ERR "%s: unknown flag %d\n",
+ tty_name(tty, buf), flag);
+ break;
+ }
+}
+
+static void
+n_tty_receive_char_lnext(struct tty_struct *tty, unsigned char c, char flag)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+
+ ldata->lnext = 0;
+ if (likely(flag == TTY_NORMAL)) {
+ if (I_ISTRIP(tty))
+ c &= 0x7f;
+ if (I_IUCLC(tty) && L_IEXTEN(tty))
+ c = tolower(c);
+ n_tty_receive_char(tty, c);
+ } else
+ n_tty_receive_char_flagged(tty, c, flag);
}
/**
* publishes read_head and canon_head
*/
-static void __receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count)
+static void
+n_tty_receive_buf_real_raw(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
{
struct n_tty_data *ldata = tty->disc_data;
- char flags = TTY_NORMAL;
- char buf[64];
+ size_t n, head;
+
+ head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
+ n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
+ n = min_t(size_t, count, n);
+ memcpy(read_buf_addr(ldata, head), cp, n);
+ ldata->read_head += n;
+ cp += n;
+ count -= n;
+
+ head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
+ n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
+ n = min_t(size_t, count, n);
+ memcpy(read_buf_addr(ldata, head), cp, n);
+ ldata->read_head += n;
+}
- if (ldata->real_raw) {
- size_t n, head;
+static void
+n_tty_receive_buf_raw(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+ char flag = TTY_NORMAL;
- head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
- n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
- n = min_t(size_t, count, n);
- memcpy(read_buf_addr(ldata, head), cp, n);
- ldata->read_head += n;
- cp += n;
- count -= n;
+ while (count--) {
+ if (fp)
+ flag = *fp++;
+ if (likely(flag == TTY_NORMAL))
+ put_tty_queue(*cp++, ldata);
+ else
+ n_tty_receive_char_flagged(tty, *cp++, flag);
+ }
+}
- head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
- n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
- n = min_t(size_t, count, n);
- memcpy(read_buf_addr(ldata, head), cp, n);
- ldata->read_head += n;
- } else {
- int i;
+static void
+n_tty_receive_buf_closing(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
+{
+ char flag = TTY_NORMAL;
- for (i = count; i; i--, cp++) {
- if (fp)
- flags = *fp++;
- switch (flags) {
- case TTY_NORMAL:
- n_tty_receive_char(tty, *cp);
- break;
- case TTY_BREAK:
- n_tty_receive_break(tty);
- break;
- case TTY_PARITY:
- case TTY_FRAME:
- n_tty_receive_parity_error(tty, *cp);
- break;
- case TTY_OVERRUN:
- n_tty_receive_overrun(tty);
- break;
- default:
- printk(KERN_ERR "%s: unknown flag %d\n",
- tty_name(tty, buf), flags);
- break;
+ while (count--) {
+ if (fp)
+ flag = *fp++;
+ if (likely(flag == TTY_NORMAL))
+ n_tty_receive_char_closing(tty, *cp++);
+ else
+ n_tty_receive_char_flagged(tty, *cp++, flag);
+ }
+}
+
+static void
+n_tty_receive_buf_standard(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+ char flag = TTY_NORMAL;
+
+ while (count--) {
+ if (fp)
+ flag = *fp++;
+ if (likely(flag == TTY_NORMAL)) {
+ unsigned char c = *cp++;
+
+ if (I_ISTRIP(tty))
+ c &= 0x7f;
+ if (I_IUCLC(tty) && L_IEXTEN(tty))
+ c = tolower(c);
+ if (L_EXTPROC(tty)) {
+ put_tty_queue(c, ldata);
+ continue;
}
+ if (!test_bit(c, ldata->char_map))
+ n_tty_receive_char_inline(tty, c);
+ else if (n_tty_receive_char_special(tty, c) && count) {
+ if (fp)
+ flag = *fp++;
+ n_tty_receive_char_lnext(tty, *cp++, flag);
+ count--;
+ }
+ } else
+ n_tty_receive_char_flagged(tty, *cp++, flag);
+ }
+}
+
+static void
+n_tty_receive_buf_fast(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+ char flag = TTY_NORMAL;
+
+ while (count--) {
+ if (fp)
+ flag = *fp++;
+ if (likely(flag == TTY_NORMAL)) {
+ unsigned char c = *cp++;
+
+ if (!test_bit(c, ldata->char_map))
+ n_tty_receive_char_fast(tty, c);
+ else if (n_tty_receive_char_special(tty, c) && count) {
+ if (fp)
+ flag = *fp++;
+ n_tty_receive_char_lnext(tty, *cp++, flag);
+ count--;
+ }
+ } else
+ n_tty_receive_char_flagged(tty, *cp++, flag);
+ }
+}
+
+static void __receive_buf(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count)
+{
+ struct n_tty_data *ldata = tty->disc_data;
+ bool preops = I_ISTRIP(tty) || (I_IUCLC(tty) && L_IEXTEN(tty));
+
+ if (ldata->real_raw)
+ n_tty_receive_buf_real_raw(tty, cp, fp, count);
+ else if (ldata->raw || (L_EXTPROC(tty) && !preops))
+ n_tty_receive_buf_raw(tty, cp, fp, count);
+ else if (tty->closing && !L_EXTPROC(tty))
+ n_tty_receive_buf_closing(tty, cp, fp, count);
+ else {
+ if (ldata->lnext) {
+ char flag = TTY_NORMAL;
+
+ if (fp)
+ flag = *fp++;
+ n_tty_receive_char_lnext(tty, *cp++, flag);
+ count--;
}
+ if (!preops && !I_PARMRK(tty))
+ n_tty_receive_buf_fast(tty, cp, fp, count);
+ else
+ n_tty_receive_buf_standard(tty, cp, fp, count);
+
flush_echoes(tty);
if (tty->ops->flush_chars)
tty->ops->flush_chars(tty);
if (waitqueue_active(&tty->read_wait))
wake_up_interruptible(&tty->read_wait);
}
-
- n_tty_check_throttle(tty);
}
static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count)
{
+ int room, n;
+
down_read(&tty->termios_rwsem);
- __receive_buf(tty, cp, fp, count);
+
+ while (1) {
+ room = receive_room(tty);
+ n = min(count, room);
+ if (!n)
+ break;
+ __receive_buf(tty, cp, fp, n);
+ cp += n;
+ if (fp)
+ fp += n;
+ count -= n;
+ }
+
+ tty->receive_room = room;
+ n_tty_check_throttle(tty);
up_read(&tty->termios_rwsem);
}
char *fp, int count)
{
struct n_tty_data *ldata = tty->disc_data;
- int room;
+ int room, n, rcvd = 0;
down_read(&tty->termios_rwsem);
- tty->receive_room = room = receive_room(tty);
- if (!room)
- ldata->no_room = 1;
- count = min(count, room);
- if (count)
- __receive_buf(tty, cp, fp, count);
+ while (1) {
+ room = receive_room(tty);
+ n = min(count, room);
+ if (!n) {
+ if (!room)
+ ldata->no_room = 1;
+ break;
+ }
+ __receive_buf(tty, cp, fp, n);
+ cp += n;
+ if (fp)
+ fp += n;
+ count -= n;
+ rcvd += n;
+ }
+ tty->receive_room = room;
+ n_tty_check_throttle(tty);
up_read(&tty->termios_rwsem);
- return count;
+ return rcvd;
}
int is_ignored(int sig)
I_ICRNL(tty) || I_INLCR(tty) || L_ICANON(tty) ||
I_IXON(tty) || L_ISIG(tty) || L_ECHO(tty) ||
I_PARMRK(tty)) {
- bitmap_zero(ldata->process_char_map, 256);
+ bitmap_zero(ldata->char_map, 256);
if (I_IGNCR(tty) || I_ICRNL(tty))
- set_bit('\r', ldata->process_char_map);
+ set_bit('\r', ldata->char_map);
if (I_INLCR(tty))
- set_bit('\n', ldata->process_char_map);
+ set_bit('\n', ldata->char_map);
if (L_ICANON(tty)) {
- set_bit(ERASE_CHAR(tty), ldata->process_char_map);
- set_bit(KILL_CHAR(tty), ldata->process_char_map);
- set_bit(EOF_CHAR(tty), ldata->process_char_map);
- set_bit('\n', ldata->process_char_map);
- set_bit(EOL_CHAR(tty), ldata->process_char_map);
+ set_bit(ERASE_CHAR(tty), ldata->char_map);
+ set_bit(KILL_CHAR(tty), ldata->char_map);
+ set_bit(EOF_CHAR(tty), ldata->char_map);
+ set_bit('\n', ldata->char_map);
+ set_bit(EOL_CHAR(tty), ldata->char_map);
if (L_IEXTEN(tty)) {
- set_bit(WERASE_CHAR(tty),
- ldata->process_char_map);
- set_bit(LNEXT_CHAR(tty),
- ldata->process_char_map);
- set_bit(EOL2_CHAR(tty),
- ldata->process_char_map);
+ set_bit(WERASE_CHAR(tty), ldata->char_map);
+ set_bit(LNEXT_CHAR(tty), ldata->char_map);
+ set_bit(EOL2_CHAR(tty), ldata->char_map);
if (L_ECHO(tty))
set_bit(REPRINT_CHAR(tty),
- ldata->process_char_map);
+ ldata->char_map);
}
}
if (I_IXON(tty)) {
- set_bit(START_CHAR(tty), ldata->process_char_map);
- set_bit(STOP_CHAR(tty), ldata->process_char_map);
+ set_bit(START_CHAR(tty), ldata->char_map);
+ set_bit(STOP_CHAR(tty), ldata->char_map);
}
if (L_ISIG(tty)) {
- set_bit(INTR_CHAR(tty), ldata->process_char_map);
- set_bit(QUIT_CHAR(tty), ldata->process_char_map);
- set_bit(SUSP_CHAR(tty), ldata->process_char_map);
+ set_bit(INTR_CHAR(tty), ldata->char_map);
+ set_bit(QUIT_CHAR(tty), ldata->char_map);
+ set_bit(SUSP_CHAR(tty), ldata->char_map);
}
- clear_bit(__DISABLED_CHAR, ldata->process_char_map);
+ clear_bit(__DISABLED_CHAR, ldata->char_map);
ldata->raw = 0;
ldata->real_raw = 0;
} else {
if (c < 0)
return c;
+ /*
+ * Internal serialization of reads.
+ */
+ if (file->f_flags & O_NONBLOCK) {
+ if (!mutex_trylock(&ldata->atomic_read_lock))
+ return -EAGAIN;
+ } else {
+ if (mutex_lock_interruptible(&ldata->atomic_read_lock))
+ return -ERESTARTSYS;
+ }
+
down_read(&tty->termios_rwsem);
minimum = time = 0;
}
}
- /*
- * Internal serialization of reads.
- */
- if (file->f_flags & O_NONBLOCK) {
- if (!mutex_trylock(&ldata->atomic_read_lock)) {
- up_read(&tty->termios_rwsem);
- return -EAGAIN;
- }
- } else {
- if (mutex_lock_interruptible(&ldata->atomic_read_lock)) {
- up_read(&tty->termios_rwsem);
- return -ERESTARTSYS;
- }
- }
packet = tty->packet;
add_wait_queue(&tty->read_wait, &wait);
projects / firefly-linux-kernel-4.4.55.git / blobdiff