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n_tty: Uninline tty_copy_to_user() 

Merge the multiple tty_copy_to_user() calls into a single copy
sequence within tty_copy_to_user().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Hurley 2015-11-27 14:11:02 -05:00 committed by Greg Kroah-Hartman
parent afd7f88f15
commit 679e7c2999
1 changed files with 18 additions and 15 deletions
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33
drivers/tty/n_tty.c
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@ -162,12 +162,23 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
return put_user(x, ptr);
}
static inline int tty_copy_to_user(struct tty_struct *tty,
void __user *to,
const void *from,
unsigned long n)
static int tty_copy_to_user(struct tty_struct *tty, void __user *to,
size_t tail, size_t n)
{
struct n_tty_data *ldata = tty->disc_data;
size_t size = N_TTY_BUF_SIZE - tail;
const void *from = read_buf_addr(ldata, tail);
int uncopied;
if (n > size) {
tty_audit_add_data(tty, from, size, ldata->icanon);
uncopied = copy_to_user(to, from, size);
if (uncopied)
return uncopied;
to += size;
n -= size;
from = ldata->read_buf;
}
tty_audit_add_data(tty, from, n, ldata->icanon);
return copy_to_user(to, from, n);
@ -2074,7 +2085,6 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
} else if (eol != size)
found = 1;
size = N_TTY_BUF_SIZE - tail;
n = eol - tail;
if (n > N_TTY_BUF_SIZE)
n += N_TTY_BUF_SIZE;
@ -2086,17 +2096,10 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
eof_push = !n && ldata->read_tail != ldata->line_start;
}
n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu size:%zu more:%zu\n",
__func__, eol, found, n, c, size, more);
if (n > size) {
ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), size);
if (ret)
return -EFAULT;
ret = tty_copy_to_user(tty, *b + size, ldata->read_buf, n - size);
} else
ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), n);
n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu tail:%zu more:%zu\n",
__func__, eol, found, n, c, tail, more);
ret = tty_copy_to_user(tty, *b, tail, n);
if (ret)
return -EFAULT;
*b += n;