diff options
Diffstat (limited to 'drivers/tty/tty_buffer.c')
| -rw-r--r-- | drivers/tty/tty_buffer.c | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index c043136fbe51..57eb34b2ec24 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -26,7 +26,7 @@ * Byte threshold to limit memory consumption for flip buffers. * The actual memory limit is > 2x this amount. */ -#define TTYB_MEM_LIMIT 65536 +#define TTYB_DEFAULT_MEM_LIMIT 65536 /* * We default to dicing tty buffer allocations to this many characters @@ -89,7 +89,7 @@ void tty_buffer_unlock_exclusive(struct tty_port *port) int tty_buffer_space_avail(struct tty_port *port) { - int space = TTYB_MEM_LIMIT - atomic_read(&port->buf.memory_used); + int space = port->buf.mem_limit - atomic_read(&port->buf.memory_used); return max(space, 0); } @@ -162,7 +162,7 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_port *port, size_t size) /* Should possibly check if this fails for the largest buffer we have queued and recycle that ? */ - if (atomic_read(&port->buf.memory_used) > TTYB_MEM_LIMIT) + if (atomic_read(&port->buf.memory_used) > port->buf.mem_limit) return NULL; p = kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC); if (p == NULL) @@ -536,4 +536,22 @@ void tty_buffer_init(struct tty_port *port) atomic_set(&buf->memory_used, 0); atomic_set(&buf->priority, 0); INIT_WORK(&buf->work, flush_to_ldisc); + buf->mem_limit = TTYB_DEFAULT_MEM_LIMIT; } + +/** + * tty_buffer_set_limit - change the tty buffer memory limit + * @port: tty port to change + * + * Change the tty buffer memory limit. + * Must be called before the other tty buffer functions are used. + */ + +int tty_buffer_set_limit(struct tty_port *port, int limit) +{ + if (limit < MIN_TTYB_SIZE) + return -EINVAL; + port->buf.mem_limit = limit; + return 0; +} +EXPORT_SYMBOL_GPL(tty_buffer_set_limit); |