Commit 60f41e84 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Revert "tty: hvc: pass DMA capable memory to put_chars()" 

This reverts commit 0986d7bc.

It still has some issues and needs to be dropped at this point in time.

Link: https://lore.kernel.org/r/208f7a41-a9fa-630c-cb44-c37c503f3a72@kernel.org


Reported-by: default avatarJiri Slaby <jirislaby@kernel.org>
Cc: Xianting Tian <xianting.tian@linux.alibaba.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 45965252

drivers/tty/hvc/hvc_console.c

+15 −21
Original line number Diff line number Diff line
@@ -41,6 +41,16 @@ 
 */

#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */



/*

 * 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 N_OUTBUF	16

#define N_INBUF		16



#define __ALIGNED__ __attribute__((__aligned__(L1_CACHE_BYTES)))



static struct tty_driver *hvc_driver;

static struct task_struct *hvc_task;
@@ -132,7 +142,6 @@ static int hvc_flush(struct hvc_struct *hp) 
static const struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES];

static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =

	{[0 ... MAX_NR_HVC_CONSOLES - 1] = -1};

static struct hvc_struct *cons_hvcs[MAX_NR_HVC_CONSOLES];



/*

 * Console APIs, NOT TTY.  These APIs are available immediately when
@@ -142,11 +151,9 @@ static struct hvc_struct *cons_hvcs[MAX_NR_HVC_CONSOLES]; 
static void hvc_console_print(struct console *co, const char *b,

			      unsigned count)

{

	char *c;

	char c[N_OUTBUF] __ALIGNED__;

	unsigned i = 0, n = 0;

	int r, donecr = 0, index = co->index;

	unsigned long flags;

	struct hvc_struct *hp;



	/* Console access attempt outside of acceptable console range. */

	if (index >= MAX_NR_HVC_CONSOLES)
@@ -156,13 +163,6 @@ static void hvc_console_print(struct console *co, const char *b, 
	if (vtermnos[index] == -1)

		return;



	hp = cons_hvcs[index];

	if (!hp)

		return;



	c = hp->cons_outbuf;



	spin_lock_irqsave(&hp->cons_outbuf_lock, flags);

	while (count > 0 || i > 0) {

		if (count > 0 && i < sizeof(c)) {

			if (b[n] == '\n' && !donecr) {
@@ -191,7 +191,6 @@ static void hvc_console_print(struct console *co, const char *b, 
			}

		}

	}

	spin_unlock_irqrestore(&hp->cons_outbuf_lock, flags);

	hvc_console_flush(cons_ops[index], vtermnos[index]);

}
@@ -879,13 +878,9 @@ static void hvc_poll_put_char(struct tty_driver *driver, int line, char ch) 
	struct tty_struct *tty = driver->ttys[0];

	struct hvc_struct *hp = tty->driver_data;

	int n;

	unsigned long flags;



	do {

		spin_lock_irqsave(&hp->cons_outbuf_lock, flags);

		hp->cons_outbuf[0] = ch;

		n = hp->ops->put_chars(hp->vtermno, &hp->cons_outbuf[0], 1);

		spin_unlock_irqrestore(&hp->cons_outbuf_lock, flags);

		n = hp->ops->put_chars(hp->vtermno, &ch, 1);

	} while (n <= 0);

}

#endif
@@ -927,7 +922,8 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data, 
			return ERR_PTR(err);

	}



	hp = kzalloc(struct_size(hp, outbuf, outbuf_size), GFP_KERNEL);

	hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,

			GFP_KERNEL);

	if (!hp)

		return ERR_PTR(-ENOMEM);
@@ -935,13 +931,13 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data, 
	hp->data = data;

	hp->ops = ops;

	hp->outbuf_size = outbuf_size;

	hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];



	tty_port_init(&hp->port);

	hp->port.ops = &hvc_port_ops;



	INIT_WORK(&hp->tty_resize, hvc_set_winsz);

	spin_lock_init(&hp->lock);

	spin_lock_init(&hp->cons_outbuf_lock);

	mutex_lock(&hvc_structs_mutex);



	/*
@@ -968,7 +964,6 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data, 
	if (i < MAX_NR_HVC_CONSOLES) {

		cons_ops[i] = ops;

		vtermnos[i] = vtermno;

		cons_hvcs[i] = hp;

	}



	list_add_tail(&(hp->next), &hvc_structs);
@@ -993,7 +988,6 @@ int hvc_remove(struct hvc_struct *hp) 
	if (hp->index < MAX_NR_HVC_CONSOLES) {

		vtermnos[hp->index] = -1;

		cons_ops[hp->index] = NULL;

		cons_hvcs[hp->index] = NULL;

	}



	/* Don't whack hp->irq because tty_hangup() will need to free the irq. */

drivers/tty/hvc/hvc_console.h

+1 −20
Original line number Diff line number Diff line
@@ -32,21 +32,12 @@ 
 */

#define HVC_ALLOC_TTY_ADAPTERS	8



/*

 * 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 N_OUTBUF	16

#define N_INBUF		16



#define __ALIGNED__ __attribute__((__aligned__(L1_CACHE_BYTES)))



struct hvc_struct {

	struct tty_port port;

	spinlock_t lock;

	int index;

	int do_wakeup;

	char *outbuf;

	int outbuf_size;

	int n_outbuf;

	uint32_t vtermno;
@@ -57,16 +48,6 @@ struct hvc_struct { 
	struct work_struct tty_resize;

	struct list_head next;

	unsigned long flags;



	/*

	 * the buf and its lock are used in hvc console api for putting chars,

	 * and also used in hvc_poll_put_char() for putting single char.

	 */

	spinlock_t cons_outbuf_lock;

	char cons_outbuf[N_OUTBUF] __ALIGNED__;



	/* the buf is used for putting chars to tty */

	char outbuf[] __ALIGNED__;

};



/* implemented by a low level driver */