diff options
Diffstat (limited to 'drivers/char/hvc_console.c')
| -rw-r--r-- | drivers/char/hvc_console.c | 69 |
1 files changed, 29 insertions, 40 deletions
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index a94c5b0cac52..2b6a56b2bf35 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -39,8 +39,10 @@ #include <linux/sched.h> #include <linux/spinlock.h> #include <linux/delay.h> + #include <asm/uaccess.h> -#include <asm/hvconsole.h> + +#include "hvc_console.h" #define HVC_MAJOR 229 #define HVC_MINOR 0 @@ -54,17 +56,14 @@ #define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */ /* - * The Linux TTY code does not support dynamic addition of tty derived devices - * so we need to know how many tty devices we might need when space is allocated - * for the tty device. Since this driver supports hotplug of vty adapters we - * need to make sure we have enough allocated. + * These sizes are most efficient for vio, because they are the + * native transfer size. We could make them selectable in the + * future to better deal with backends that want other buffer sizes. */ -#define HVC_ALLOC_TTY_ADAPTERS 8 - #define N_OUTBUF 16 #define N_INBUF 16 -#define __ALIGNED__ __attribute__((__aligned__(8))) +#define __ALIGNED__ __attribute__((__aligned__(sizeof(long)))) static struct tty_driver *hvc_driver; static struct task_struct *hvc_task; @@ -154,7 +153,7 @@ static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] = void hvc_console_print(struct console *co, const char *b, unsigned count) { - char c[16] __ALIGNED__; + char c[N_OUTBUF] __ALIGNED__; unsigned i = 0, n = 0; int r, donecr = 0, index = co->index; @@ -473,8 +472,10 @@ static void hvc_push(struct hvc_struct *hp) n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); if (n <= 0) { - if (n == 0) + if (n == 0) { + hp->do_wakeup = 1; return; + } /* throw away output on error; this happens when there is no session connected to the vterm. */ hp->n_outbuf = 0; @@ -486,12 +487,19 @@ static void hvc_push(struct hvc_struct *hp) hp->do_wakeup = 1; } -static inline int __hvc_write_kernel(struct hvc_struct *hp, - const unsigned char *buf, int count) +static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) { + struct hvc_struct *hp = tty->driver_data; unsigned long flags; int rsize, written = 0; + /* This write was probably executed during a tty close. */ + if (!hp) + return -EPIPE; + + if (hp->count <= 0) + return -EIO; + spin_lock_irqsave(&hp->lock, flags); /* Push pending writes */ @@ -510,26 +518,8 @@ static inline int __hvc_write_kernel(struct hvc_struct *hp, } spin_unlock_irqrestore(&hp->lock, flags); - return written; -} -static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) -{ - struct hvc_struct *hp = tty->driver_data; - int written; - - /* This write was probably executed during a tty close. */ - if (!hp) - return -EPIPE; - - if (hp->count <= 0) - return -EIO; - - written = __hvc_write_kernel(hp, buf, count); - /* * Racy, but harmless, kick thread if there is still pending data. - * There really is nothing wrong with kicking the thread, even if there - * is no buffered data. */ if (hp->n_outbuf) hvc_kick(); @@ -614,6 +604,13 @@ static int hvc_poll(struct hvc_struct *hp) spin_unlock_irqrestore(&hp->lock, flags); tty_hangup(tty); spin_lock_irqsave(&hp->lock, flags); + } else if ( n == -EAGAIN ) { + /* + * Some back-ends can only ensure a certain min + * num of bytes read, which may be > 'count'. + * Let the tty clear the flip buff to make room. + */ + poll_mask |= HVC_POLL_READ; } break; } @@ -635,16 +632,7 @@ static int hvc_poll(struct hvc_struct *hp) tty_insert_flip_char(tty, buf[i], 0); } - /* - * Account for the total amount read in one loop, and if above - * 64 bytes, we do a quick schedule loop to let the tty grok - * the data and eventually throttle us. - */ read_total += n; - if (read_total >= 64) { - poll_mask |= HVC_POLL_QUICK; - break; - } } throttled: /* Wakeup write queue if necessary */ @@ -767,7 +755,8 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq, * see if this vterm id matches one registered for console. */ for (i=0; i < MAX_NR_HVC_CONSOLES; i++) - if (vtermnos[i] == hp->vtermno) + if (vtermnos[i] == hp->vtermno && + cons_ops[i] == hp->ops) break; /* no matching slot, just use a counter */ |