V4L/DVB: pvrusb2: Fix kernel oops at device unregistration
[safe/jmp/linux-2.6] / drivers / s390 / char / sclp_tty.c
index 6f43e04..8258d59 100644 (file)
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
 #include <linux/tty_flip.h>
-#include <linux/sched.h>
-#include <linux/wait.h>
-#include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/gfp.h>
 #include <asm/uaccess.h>
 
 #include "ctrlchar.h"
@@ -26,8 +24,6 @@
 #include "sclp_rw.h"
 #include "sclp_tty.h"
 
-#define SCLP_TTY_PRINT_HEADER "sclp tty driver: "
-
 /*
  * size of a buffer that collects single characters coming in
  * via sclp_tty_put_char()
@@ -51,8 +47,6 @@ static int sclp_tty_buffer_count;
 static struct sclp_buffer *sclp_ttybuf;
 /* Timer for delayed output of console messages. */
 static struct timer_list sclp_tty_timer;
-/* Waitqueue to wait for buffers to get empty. */
-static wait_queue_head_t sclp_tty_waitq;
 
 static struct tty_struct *sclp_tty;
 static unsigned char sclp_tty_chars[SCLP_TTY_BUF_SIZE];
@@ -60,21 +54,11 @@ static unsigned short int sclp_tty_chars_count;
 
 struct tty_driver *sclp_tty_driver;
 
-extern struct termios  tty_std_termios;
+static int sclp_tty_tolower;
+static int sclp_tty_columns = 80;
 
-static struct sclp_ioctls sclp_ioctls;
-static struct sclp_ioctls sclp_ioctls_init =
-{
-       8,                      /* 1 hor. tab. = 8 spaces */
-       0,                      /* no echo of input by this driver */
-       80,                     /* 80 characters/line */
-       1,                      /* write after 1/10 s without final new line */
-       MAX_KMEM_PAGES,         /* quick fix: avoid __alloc_pages */
-       MAX_KMEM_PAGES,         /* take 32/64 pages from kernel memory, */
-       0,                      /* do not convert to lower case */
-       0x6c                    /* to seprate upper and lower case */
-                               /* ('%' in EBCDIC) */
-};
+#define SPACES_PER_TAB 8
+#define CASE_DELIMITER 0x6c /* to separate upper and lower case (% in EBCDIC) */
 
 /* This routine is called whenever we try to open a SCLP terminal. */
 static int
@@ -95,136 +79,6 @@ sclp_tty_close(struct tty_struct *tty, struct file *filp)
        sclp_tty = NULL;
 }
 
-/* execute commands to control the i/o behaviour of the SCLP tty at runtime */
-static int
-sclp_tty_ioctl(struct tty_struct *tty, struct file * file,
-              unsigned int cmd, unsigned long arg)
-{
-       unsigned long flags;
-       unsigned int obuf;
-       int check;
-       int rc;
-
-       if (tty->flags & (1 << TTY_IO_ERROR))
-               return -EIO;
-       rc = 0;
-       check = 0;
-       switch (cmd) {
-       case TIOCSCLPSHTAB:
-               /* set width of horizontal tab  */
-               if (get_user(sclp_ioctls.htab, (unsigned short __user *) arg))
-                       rc = -EFAULT;
-               else
-                       check = 1;
-               break;
-       case TIOCSCLPGHTAB:
-               /* get width of horizontal tab  */
-               if (put_user(sclp_ioctls.htab, (unsigned short __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSECHO:
-               /* enable/disable echo of input */
-               if (get_user(sclp_ioctls.echo, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGECHO:
-               /* Is echo of input enabled ?  */
-               if (put_user(sclp_ioctls.echo, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSCOLS:
-               /* set number of columns for output  */
-               if (get_user(sclp_ioctls.columns, (unsigned short __user *) arg))
-                       rc = -EFAULT;
-               else
-                       check = 1;
-               break;
-       case TIOCSCLPGCOLS:
-               /* get number of columns for output  */
-               if (put_user(sclp_ioctls.columns, (unsigned short __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSNL:
-               /* enable/disable writing without final new line character  */
-               if (get_user(sclp_ioctls.final_nl, (signed char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGNL:
-               /* Is writing without final new line character enabled ?  */
-               if (put_user(sclp_ioctls.final_nl, (signed char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSOBUF:
-               /*
-                * set the maximum buffers size for output, will be rounded
-                * up to next 4kB boundary and stored as number of SCCBs
-                * (4kB Buffers) limitation: 256 x 4kB
-                */
-               if (get_user(obuf, (unsigned int __user *) arg) == 0) {
-                       if (obuf & 0xFFF)
-                               sclp_ioctls.max_sccb = (obuf >> 12) + 1;
-                       else
-                               sclp_ioctls.max_sccb = (obuf >> 12);
-               } else
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGOBUF:
-               /* get the maximum buffers size for output  */
-               obuf = sclp_ioctls.max_sccb << 12;
-               if (put_user(obuf, (unsigned int __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGKBUF:
-               /* get the number of buffers got from kernel at startup */
-               if (put_user(sclp_ioctls.kmem_sccb, (unsigned short __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSCASE:
-               /* enable/disable conversion from upper to lower case */
-               if (get_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGCASE:
-               /* Is conversion from upper to lower case of input enabled? */
-               if (put_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSDELIM:
-               /*
-                * set special character used for separating upper and
-                * lower case, 0x00 disables this feature
-                */
-               if (get_user(sclp_ioctls.delim, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPGDELIM:
-               /*
-                * get special character used for separating upper and
-                * lower case, 0x00 disables this feature
-                */
-               if (put_user(sclp_ioctls.delim, (unsigned char __user *) arg))
-                       rc = -EFAULT;
-               break;
-       case TIOCSCLPSINIT:
-               /* set initial (default) sclp ioctls  */
-               sclp_ioctls = sclp_ioctls_init;
-               check = 1;
-               break;
-       default:
-               rc = -ENOIOCTLCMD;
-               break;
-       }
-       if (check) {
-               spin_lock_irqsave(&sclp_tty_lock, flags);
-               if (sclp_ttybuf != NULL) {
-                       sclp_set_htab(sclp_ttybuf, sclp_ioctls.htab);
-                       sclp_set_columns(sclp_ttybuf, sclp_ioctls.columns);
-               }
-               spin_unlock_irqrestore(&sclp_tty_lock, flags);
-       }
-       return rc;
-}
-
 /*
  * This routine returns the numbers of characters the tty driver
  * will accept for queuing to be written.  This number is subject
@@ -271,7 +125,6 @@ sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
                                            struct sclp_buffer, list);
                spin_unlock_irqrestore(&sclp_tty_lock, flags);
        } while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
-       wake_up(&sclp_tty_waitq);
        /* check if the tty needs a wake up call */
        if (sclp_tty != NULL) {
                tty_wakeup(sclp_tty);
@@ -319,37 +172,37 @@ sclp_tty_timeout(unsigned long data)
 /*
  * Write a string to the sclp tty.
  */
-static void
-sclp_tty_write_string(const unsigned char *str, int count)
+static int sclp_tty_write_string(const unsigned char *str, int count, int may_fail)
 {
        unsigned long flags;
        void *page;
        int written;
+       int overall_written;
        struct sclp_buffer *buf;
 
        if (count <= 0)
-               return;
+               return 0;
+       overall_written = 0;
        spin_lock_irqsave(&sclp_tty_lock, flags);
        do {
                /* Create a sclp output buffer if none exists yet */
                if (sclp_ttybuf == NULL) {
                        while (list_empty(&sclp_tty_pages)) {
                                spin_unlock_irqrestore(&sclp_tty_lock, flags);
-                               if (in_interrupt())
-                                       sclp_sync_wait();
+                               if (may_fail)
+                                       goto out;
                                else
-                                       wait_event(sclp_tty_waitq,
-                                               !list_empty(&sclp_tty_pages));
+                                       sclp_sync_wait();
                                spin_lock_irqsave(&sclp_tty_lock, flags);
                        }
                        page = sclp_tty_pages.next;
                        list_del((struct list_head *) page);
-                       sclp_ttybuf = sclp_make_buffer(page,
-                                                      sclp_ioctls.columns,
-                                                      sclp_ioctls.htab);
+                       sclp_ttybuf = sclp_make_buffer(page, sclp_tty_columns,
+                                                      SPACES_PER_TAB);
                }
                /* try to write the string to the current output buffer */
                written = sclp_write(sclp_ttybuf, str, count);
+               overall_written += written;
                if (written == count)
                        break;
                /*
@@ -366,27 +219,17 @@ sclp_tty_write_string(const unsigned char *str, int count)
                count -= written;
        } while (count > 0);
        /* Setup timer to output current console buffer after 1/10 second */
-       if (sclp_ioctls.final_nl) {
-               if (sclp_ttybuf != NULL &&
-                   sclp_chars_in_buffer(sclp_ttybuf) != 0 &&
-                   !timer_pending(&sclp_tty_timer)) {
-                       init_timer(&sclp_tty_timer);
-                       sclp_tty_timer.function = sclp_tty_timeout;
-                       sclp_tty_timer.data = 0UL;
-                       sclp_tty_timer.expires = jiffies + HZ/10;
-                       add_timer(&sclp_tty_timer);
-               }
-       } else {
-               if (sclp_ttybuf != NULL &&
-                   sclp_chars_in_buffer(sclp_ttybuf) != 0) {
-                       buf = sclp_ttybuf;
-                       sclp_ttybuf = NULL;
-                       spin_unlock_irqrestore(&sclp_tty_lock, flags);
-                       __sclp_ttybuf_emit(buf);
-                       spin_lock_irqsave(&sclp_tty_lock, flags);
-               }
+       if (sclp_ttybuf && sclp_chars_in_buffer(sclp_ttybuf) &&
+           !timer_pending(&sclp_tty_timer)) {
+               init_timer(&sclp_tty_timer);
+               sclp_tty_timer.function = sclp_tty_timeout;
+               sclp_tty_timer.data = 0UL;
+               sclp_tty_timer.expires = jiffies + HZ/10;
+               add_timer(&sclp_tty_timer);
        }
        spin_unlock_irqrestore(&sclp_tty_lock, flags);
+out:
+       return overall_written;
 }
 
 /*
@@ -398,11 +241,10 @@ static int
 sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 {
        if (sclp_tty_chars_count > 0) {
-               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
                sclp_tty_chars_count = 0;
        }
-       sclp_tty_write_string(buf, count);
-       return count;
+       return sclp_tty_write_string(buf, count, 1);
 }
 
 /*
@@ -415,14 +257,15 @@ sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
  * - including previous characters from sclp_tty_put_char() and strings from
  * sclp_write() without final '\n' - will be written.
  */
-static void
+static int
 sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
 {
        sclp_tty_chars[sclp_tty_chars_count++] = ch;
        if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
-               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
                sclp_tty_chars_count = 0;
        }
+       return 1;
 }
 
 /*
@@ -433,7 +276,7 @@ static void
 sclp_tty_flush_chars(struct tty_struct *tty)
 {
        if (sclp_tty_chars_count > 0) {
-               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
                sclp_tty_chars_count = 0;
        }
 }
@@ -472,7 +315,7 @@ static void
 sclp_tty_flush_buffer(struct tty_struct *tty)
 {
        if (sclp_tty_chars_count > 0) {
-               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+               sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
                sclp_tty_chars_count = 0;
        }
 }
@@ -520,9 +363,7 @@ sclp_tty_input(unsigned char* buf, unsigned int count)
  * modifiy original string,
  * returns length of resulting string
  */
-static int
-sclp_switch_cases(unsigned char *buf, int count,
-                 unsigned char delim, int tolower)
+static int sclp_switch_cases(unsigned char *buf, int count)
 {
        unsigned char *ip, *op;
        int toggle;
@@ -532,9 +373,9 @@ sclp_switch_cases(unsigned char *buf, int count,
        ip = op = buf;
        while (count-- > 0) {
                /* compare with special character */
-               if (*ip == delim) {
+               if (*ip == CASE_DELIMITER) {
                        /* followed by another special character? */
-                       if (count && ip[1] == delim) {
+                       if (count && ip[1] == CASE_DELIMITER) {
                                /*
                                 * ... then put a single copy of the special
                                 * character to the output string
@@ -553,7 +394,7 @@ sclp_switch_cases(unsigned char *buf, int count,
                        /* not the special character */
                        if (toggle)
                                /* but case switching is on */
-                               if (tolower)
+                               if (sclp_tty_tolower)
                                        /* switch to uppercase */
                                        *op++ = _ebc_toupper[(int) *ip++];
                                else
@@ -573,30 +414,12 @@ sclp_get_input(unsigned char *start, unsigned char *end)
        int count;
 
        count = end - start;
-       /*
-        * if set in ioctl convert EBCDIC to lower case
-        * (modify original input in SCCB)
-        */
-       if (sclp_ioctls.tolower)
+       if (sclp_tty_tolower)
                EBC_TOLOWER(start, count);
-
-       /*
-        * if set in ioctl find out characters in lower or upper case
-        * (depends on current case) separated by a special character,
-        * works on EBCDIC
-        */
-       if (sclp_ioctls.delim)
-               count = sclp_switch_cases(start, count,
-                                         sclp_ioctls.delim,
-                                         sclp_ioctls.tolower);
-
+       count = sclp_switch_cases(start, count);
        /* convert EBCDIC to ASCII (modify original input in SCCB) */
        sclp_ebcasc_str(start, count);
 
-       /* if set in ioctl write operators input to console  */
-       if (sclp_ioctls.echo)
-               sclp_tty_write(sclp_tty, start, count);
-
        /* transfer input to high level driver */
        sclp_tty_input(start, count);
 }
@@ -651,7 +474,7 @@ sclp_eval_textcmd(struct gds_subvector *start,
        subvec = start;
        while (subvec < end) {
                subvec = find_gds_subvector(subvec, end,
-                                           GDS_KEY_SelfDefTextMsg);
+                                           GDS_KEY_SELFDEFTEXTMSG);
                if (!subvec)
                        break;
                sclp_eval_selfdeftextmsg((struct gds_subvector *)(subvec + 1),
@@ -667,7 +490,7 @@ sclp_eval_cpmsu(struct gds_vector *start, struct gds_vector *end)
 
        vec = start;
        while (vec < end) {
-               vec = find_gds_vector(vec, end, GDS_ID_TextCmd);
+               vec = find_gds_vector(vec, end, GDS_ID_TEXTCMD);
                if (!vec)
                        break;
                sclp_eval_textcmd((struct gds_subvector *)(vec + 1),
@@ -706,7 +529,7 @@ sclp_tty_state_change(struct sclp_register *reg)
 
 static struct sclp_register sclp_input_event =
 {
-       .receive_mask = EvTyp_OpCmd_Mask | EvTyp_PMsgCmd_Mask,
+       .receive_mask = EVTYP_OPCMD_MASK | EVTYP_PMSGCMD_MASK,
        .state_change_fn = sclp_tty_state_change,
        .receiver_fn = sclp_tty_receiver
 };
@@ -720,10 +543,9 @@ static const struct tty_operations sclp_ops = {
        .write_room = sclp_tty_write_room,
        .chars_in_buffer = sclp_tty_chars_in_buffer,
        .flush_buffer = sclp_tty_flush_buffer,
-       .ioctl = sclp_tty_ioctl,
 };
 
-int __init
+static int __init
 sclp_tty_init(void)
 {
        struct tty_driver *driver;
@@ -739,9 +561,6 @@ sclp_tty_init(void)
 
        rc = sclp_rw_init();
        if (rc) {
-               printk(KERN_ERR SCLP_TTY_PRINT_HEADER
-                      "could not register tty - "
-                      "sclp_rw_init returned %d\n", rc);
                put_tty_driver(driver);
                return rc;
        }
@@ -757,7 +576,6 @@ sclp_tty_init(void)
        }
        INIT_LIST_HEAD(&sclp_tty_outqueue);
        spin_lock_init(&sclp_tty_lock);
-       init_waitqueue_head(&sclp_tty_waitq);
        init_timer(&sclp_tty_timer);
        sclp_ttybuf = NULL;
        sclp_tty_buffer_count = 0;
@@ -766,11 +584,10 @@ sclp_tty_init(void)
                 * save 4 characters for the CPU number
                 * written at start of each line by VM/CP
                 */
-               sclp_ioctls_init.columns = 76;
+               sclp_tty_columns = 76;
                /* case input lines to lowercase */
-               sclp_ioctls_init.tolower = 1;
+               sclp_tty_tolower = 1;
        }
-       sclp_ioctls = sclp_ioctls_init;
        sclp_tty_chars_count = 0;
        sclp_tty = NULL;
 
@@ -795,9 +612,6 @@ sclp_tty_init(void)
        tty_set_operations(driver, &sclp_ops);
        rc = tty_register_driver(driver);
        if (rc) {
-               printk(KERN_ERR SCLP_TTY_PRINT_HEADER
-                      "could not register tty - "
-                      "tty_register_driver returned %d\n", rc);
                put_tty_driver(driver);
                return rc;
        }