diff options
Diffstat (limited to 'drivers/char/tty_io.c')
| -rw-r--r-- | drivers/char/tty_io.c | 71 |
1 files changed, 44 insertions, 27 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 613b2f967..4c0d29662 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -57,6 +57,9 @@ * * Added support for a Unix98-style ptmx device. * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 + * + * Reduced memory usage for older ARM systems + * -- Russell King <rmk@arm.linux.org.uk> */ #include <linux/config.h> @@ -111,7 +114,7 @@ extern void con_init_devfs (void); #define CHECK_TTY_COUNT 1 struct termios tty_std_termios; /* for the benefit of tty drivers */ -struct tty_driver *tty_drivers = NULL; /* linked list of tty drivers */ +struct tty_driver *tty_drivers; /* linked list of tty drivers */ struct tty_ldisc ldiscs[NR_LDISCS]; /* line disc dispatch table */ #ifdef CONFIG_UNIX98_PTYS @@ -123,7 +126,7 @@ extern struct tty_driver pts_driver[]; /* Unix98 pty slaves; for /dev/ptmx */ * redirect is the pseudo-tty that console output * is redirected to if asked by TIOCCONS. */ -struct tty_struct * redirect = NULL; +struct tty_struct * redirect; static void initialize_tty_struct(struct tty_struct *tty); @@ -135,35 +138,49 @@ static int tty_release(struct inode *, struct file *); int tty_ioctl(struct inode * inode, struct file * file, unsigned int cmd, unsigned long arg); static int tty_fasync(int fd, struct file * filp, int on); -#ifdef CONFIG_SX extern int sx_init (void); -#endif -#if defined(CONFIG_MVME162_SCC) || defined(CONFIG_BVME6000_SCC) || defined(CONFIG_MVME147_SCC) extern int vme_scc_init (void); extern long vme_scc_console_init(void); -#endif -#ifdef CONFIG_SERIAL167 extern int serial167_init(void); extern long serial167_console_init(void); -#endif -#if (defined(CONFIG_8xx) || defined(CONFIG_8260)) extern void console_8xx_init(void); extern int rs_8xx_init(void); -#endif /* CONFIG_8xx */ -#ifdef CONFIG_SGI_SERIAL -extern void sgi_serial_console_init(void); -#endif -#ifdef CONFIG_HWC extern void hwc_console_init(void); -#endif -#ifdef CONFIG_3215 extern void con3215_init(void); -#endif /* CONFIG_3215 */ - +extern void rs285_console_init(void); +extern void rs285_init(void); +extern void sa1100_rs_console_init(void); +extern void sa1100_rs_init(void); +extern void sgi_serial_console_init(void); #ifndef MIN #define MIN(a,b) ((a) < (b) ? (a) : (b)) #endif +#ifndef MAX +#define MAX(a,b) ((a) < (b) ? (b) : (a)) +#endif + +static inline struct tty_struct *alloc_tty_struct(void) +{ + struct tty_struct *tty; + + if (PAGE_SIZE > 8192) { + tty = kmalloc(sizeof(struct tty_struct), GFP_KERNEL); + if (tty) + memset(tty, 0, sizeof(struct tty_struct)); + } else + tty = (struct tty_struct *)get_zeroed_page(GFP_KERNEL); + + return tty; +} + +static inline void free_tty_struct(struct tty_struct *tty) +{ + if (PAGE_SIZE > 8192) + kfree(tty); + else + free_page((unsigned long) tty); +} /* * This routine returns the name of tty. @@ -695,7 +712,7 @@ static inline ssize_t do_tty_write( unlock_kernel(); } else { for (;;) { - unsigned long size = PAGE_SIZE*2; + unsigned long size = MAX(PAGE_SIZE*2,16384); if (size > count) size = count; lock_kernel(); @@ -826,7 +843,7 @@ static int init_dev(kdev_t device, struct tty_struct **ret_tty) tp = o_tp = NULL; ltp = o_ltp = NULL; - tty = (struct tty_struct*) get_zeroed_page(GFP_KERNEL); + tty = alloc_tty_struct(); if(!tty) goto fail_no_mem; initialize_tty_struct(tty); @@ -852,7 +869,7 @@ static int init_dev(kdev_t device, struct tty_struct **ret_tty) } if (driver->type == TTY_DRIVER_TYPE_PTY) { - o_tty = (struct tty_struct *) get_zeroed_page(GFP_KERNEL); + o_tty = alloc_tty_struct(); if (!o_tty) goto free_mem_out; initialize_tty_struct(o_tty); @@ -972,12 +989,12 @@ free_mem_out: if (o_tp) kfree_s(o_tp, sizeof(struct termios)); if (o_tty) - free_page((unsigned long) o_tty); + free_tty_struct(o_tty); if (ltp) kfree_s(ltp, sizeof(struct termios)); if (tp) kfree_s(tp, sizeof(struct termios)); - free_page((unsigned long) tty); + free_tty_struct(tty); fail_no_mem: retval = -ENOMEM; @@ -1008,7 +1025,7 @@ static void release_mem(struct tty_struct *tty, int idx) } o_tty->magic = 0; (*o_tty->driver.refcount)--; - free_page((unsigned long) o_tty); + free_tty_struct(o_tty); } tty->driver.table[idx] = NULL; @@ -1019,7 +1036,7 @@ static void release_mem(struct tty_struct *tty, int idx) } tty->magic = 0; (*tty->driver.refcount)--; - free_page((unsigned long) tty); + free_tty_struct(tty); } /* @@ -1400,9 +1417,9 @@ init_dev_done: static int nr_warns = 0; if (nr_warns < 5) { printk(KERN_WARNING "tty_io.c: " - "process %d (%s) used obsolete /dev/%s - " + "process %d (%s) used obsolete /dev/%s - " "update software to use /dev/ttyS%d\n", - current->pid, current->comm, + current->pid, current->comm, tty_name(tty, buf), TTY_NUMBER(tty)); nr_warns++; } |