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Diffstat (limited to 'drivers/char/vc_screen.c')
-rw-r--r--drivers/char/vc_screen.c644
1 files changed, 0 insertions, 644 deletions
diff --git a/drivers/char/vc_screen.c b/drivers/char/vc_screen.c
deleted file mode 100644
index 273ab44cc91d..000000000000
--- a/drivers/char/vc_screen.c
+++ /dev/null
@@ -1,644 +0,0 @@
-/*
- * linux/drivers/char/vc_screen.c
- *
- * Provide access to virtual console memory.
- * /dev/vcs0: the screen as it is being viewed right now (possibly scrolled)
- * /dev/vcsN: the screen of /dev/ttyN (1 <= N <= 63)
- * [minor: N]
- *
- * /dev/vcsaN: idem, but including attributes, and prefixed with
- * the 4 bytes lines,columns,x,y (as screendump used to give).
- * Attribute/character pair is in native endianity.
- * [minor: N+128]
- *
- * This replaces screendump and part of selection, so that the system
- * administrator can control access using file system permissions.
- *
- * aeb@cwi.nl - efter Friedas begravelse - 950211
- *
- * machek@k332.feld.cvut.cz - modified not to send characters to wrong console
- * - fixed some fatal off-by-one bugs (0-- no longer == -1 -> looping and looping and looping...)
- * - making it shorter - scr_readw are macros which expand in PRETTY long code
- */
-
-#include <linux/kernel.h>
-#include <linux/major.h>
-#include <linux/errno.h>
-#include <linux/tty.h>
-#include <linux/interrupt.h>
-#include <linux/mm.h>
-#include <linux/init.h>
-#include <linux/mutex.h>
-#include <linux/vt_kern.h>
-#include <linux/selection.h>
-#include <linux/kbd_kern.h>
-#include <linux/console.h>
-#include <linux/device.h>
-#include <linux/smp_lock.h>
-#include <linux/sched.h>
-#include <linux/fs.h>
-#include <linux/poll.h>
-#include <linux/signal.h>
-#include <linux/slab.h>
-#include <linux/notifier.h>
-
-#include <asm/uaccess.h>
-#include <asm/byteorder.h>
-#include <asm/unaligned.h>
-
-#undef attr
-#undef org
-#undef addr
-#define HEADER_SIZE 4
-
-struct vcs_poll_data {
- struct notifier_block notifier;
- unsigned int cons_num;
- bool seen_last_update;
- wait_queue_head_t waitq;
- struct fasync_struct *fasync;
-};
-
-static int
-vcs_notifier(struct notifier_block *nb, unsigned long code, void *_param)
-{
- struct vt_notifier_param *param = _param;
- struct vc_data *vc = param->vc;
- struct vcs_poll_data *poll =
- container_of(nb, struct vcs_poll_data, notifier);
- int currcons = poll->cons_num;
-
- if (code != VT_UPDATE)
- return NOTIFY_DONE;
-
- if (currcons == 0)
- currcons = fg_console;
- else
- currcons--;
- if (currcons != vc->vc_num)
- return NOTIFY_DONE;
-
- poll->seen_last_update = false;
- wake_up_interruptible(&poll->waitq);
- kill_fasync(&poll->fasync, SIGIO, POLL_IN);
- return NOTIFY_OK;
-}
-
-static void
-vcs_poll_data_free(struct vcs_poll_data *poll)
-{
- unregister_vt_notifier(&poll->notifier);
- kfree(poll);
-}
-
-static struct vcs_poll_data *
-vcs_poll_data_get(struct file *file)
-{
- struct vcs_poll_data *poll = file->private_data;
-
- if (poll)
- return poll;
-
- poll = kzalloc(sizeof(*poll), GFP_KERNEL);
- if (!poll)
- return NULL;
- poll->cons_num = iminor(file->f_path.dentry->d_inode) & 127;
- init_waitqueue_head(&poll->waitq);
- poll->notifier.notifier_call = vcs_notifier;
- if (register_vt_notifier(&poll->notifier) != 0) {
- kfree(poll);
- return NULL;
- }
-
- /*
- * This code may be called either through ->poll() or ->fasync().
- * If we have two threads using the same file descriptor, they could
- * both enter this function, both notice that the structure hasn't
- * been allocated yet and go ahead allocating it in parallel, but
- * only one of them must survive and be shared otherwise we'd leak
- * memory with a dangling notifier callback.
- */
- spin_lock(&file->f_lock);
- if (!file->private_data) {
- file->private_data = poll;
- } else {
- /* someone else raced ahead of us */
- vcs_poll_data_free(poll);
- poll = file->private_data;
- }
- spin_unlock(&file->f_lock);
-
- return poll;
-}
-
-static int
-vcs_size(struct inode *inode)
-{
- int size;
- int minor = iminor(inode);
- int currcons = minor & 127;
- struct vc_data *vc;
-
- if (currcons == 0)
- currcons = fg_console;
- else
- currcons--;
- if (!vc_cons_allocated(currcons))
- return -ENXIO;
- vc = vc_cons[currcons].d;
-
- size = vc->vc_rows * vc->vc_cols;
-
- if (minor & 128)
- size = 2*size + HEADER_SIZE;
- return size;
-}
-
-static loff_t vcs_lseek(struct file *file, loff_t offset, int orig)
-{
- int size;
-
- mutex_lock(&con_buf_mtx);
- size = vcs_size(file->f_path.dentry->d_inode);
- switch (orig) {
- default:
- mutex_unlock(&con_buf_mtx);
- return -EINVAL;
- case 2:
- offset += size;
- break;
- case 1:
- offset += file->f_pos;
- case 0:
- break;
- }
- if (offset < 0 || offset > size) {
- mutex_unlock(&con_buf_mtx);
- return -EINVAL;
- }
- file->f_pos = offset;
- mutex_unlock(&con_buf_mtx);
- return file->f_pos;
-}
-
-
-static ssize_t
-vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
-{
- struct inode *inode = file->f_path.dentry->d_inode;
- unsigned int currcons = iminor(inode);
- struct vc_data *vc;
- struct vcs_poll_data *poll;
- long pos;
- long viewed, attr, read;
- int col, maxcol;
- unsigned short *org = NULL;
- ssize_t ret;
-
- mutex_lock(&con_buf_mtx);
-
- pos = *ppos;
-
- /* Select the proper current console and verify
- * sanity of the situation under the console lock.
- */
- acquire_console_sem();
-
- attr = (currcons & 128);
- currcons = (currcons & 127);
- if (currcons == 0) {
- currcons = fg_console;
- viewed = 1;
- } else {
- currcons--;
- viewed = 0;
- }
- ret = -ENXIO;
- if (!vc_cons_allocated(currcons))
- goto unlock_out;
- vc = vc_cons[currcons].d;
-
- ret = -EINVAL;
- if (pos < 0)
- goto unlock_out;
- poll = file->private_data;
- if (count && poll)
- poll->seen_last_update = true;
- read = 0;
- ret = 0;
- while (count) {
- char *con_buf0, *con_buf_start;
- long this_round, size;
- ssize_t orig_count;
- long p = pos;
-
- /* Check whether we are above size each round,
- * as copy_to_user at the end of this loop
- * could sleep.
- */
- size = vcs_size(inode);
- if (pos >= size)
- break;
- if (count > size - pos)
- count = size - pos;
-
- this_round = count;
- if (this_round > CON_BUF_SIZE)
- this_round = CON_BUF_SIZE;
-
- /* Perform the whole read into the local con_buf.
- * Then we can drop the console spinlock and safely
- * attempt to move it to userspace.
- */
-
- con_buf_start = con_buf0 = con_buf;
- orig_count = this_round;
- maxcol = vc->vc_cols;
- if (!attr) {
- org = screen_pos(vc, p, viewed);
- col = p % maxcol;
- p += maxcol - col;
- while (this_round-- > 0) {
- *con_buf0++ = (vcs_scr_readw(vc, org++) & 0xff);
- if (++col == maxcol) {
- org = screen_pos(vc, p, viewed);
- col = 0;
- p += maxcol;
- }
- }
- } else {
- if (p < HEADER_SIZE) {
- size_t tmp_count;
-
- con_buf0[0] = (char)vc->vc_rows;
- con_buf0[1] = (char)vc->vc_cols;
- getconsxy(vc, con_buf0 + 2);
-
- con_buf_start += p;
- this_round += p;
- if (this_round > CON_BUF_SIZE) {
- this_round = CON_BUF_SIZE;
- orig_count = this_round - p;
- }
-
- tmp_count = HEADER_SIZE;
- if (tmp_count > this_round)
- tmp_count = this_round;
-
- /* Advance state pointers and move on. */
- this_round -= tmp_count;
- p = HEADER_SIZE;
- con_buf0 = con_buf + HEADER_SIZE;
- /* If this_round >= 0, then p is even... */
- } else if (p & 1) {
- /* Skip first byte for output if start address is odd
- * Update region sizes up/down depending on free
- * space in buffer.
- */
- con_buf_start++;
- if (this_round < CON_BUF_SIZE)
- this_round++;
- else
- orig_count--;
- }
- if (this_round > 0) {
- unsigned short *tmp_buf = (unsigned short *)con_buf0;
-
- p -= HEADER_SIZE;
- p /= 2;
- col = p % maxcol;
-
- org = screen_pos(vc, p, viewed);
- p += maxcol - col;
-
- /* Buffer has even length, so we can always copy
- * character + attribute. We do not copy last byte
- * to userspace if this_round is odd.
- */
- this_round = (this_round + 1) >> 1;
-
- while (this_round) {
- *tmp_buf++ = vcs_scr_readw(vc, org++);
- this_round --;
- if (++col == maxcol) {
- org = screen_pos(vc, p, viewed);
- col = 0;
- p += maxcol;
- }
- }
- }
- }
-
- /* Finally, release the console semaphore while we push
- * all the data to userspace from our temporary buffer.
- *
- * AKPM: Even though it's a semaphore, we should drop it because
- * the pagefault handling code may want to call printk().
- */
-
- release_console_sem();
- ret = copy_to_user(buf, con_buf_start, orig_count);
- acquire_console_sem();
-
- if (ret) {
- read += (orig_count - ret);
- ret = -EFAULT;
- break;
- }
- buf += orig_count;
- pos += orig_count;
- read += orig_count;
- count -= orig_count;
- }
- *ppos += read;
- if (read)
- ret = read;
-unlock_out:
- release_console_sem();
- mutex_unlock(&con_buf_mtx);
- return ret;
-}
-
-static ssize_t
-vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
-{
- struct inode *inode = file->f_path.dentry->d_inode;
- unsigned int currcons = iminor(inode);
- struct vc_data *vc;
- long pos;
- long viewed, attr, size, written;
- char *con_buf0;
- int col, maxcol;
- u16 *org0 = NULL, *org = NULL;
- size_t ret;
-
- mutex_lock(&con_buf_mtx);
-
- pos = *ppos;
-
- /* Select the proper current console and verify
- * sanity of the situation under the console lock.
- */
- acquire_console_sem();
-
- attr = (currcons & 128);
- currcons = (currcons & 127);
-
- if (currcons == 0) {
- currcons = fg_console;
- viewed = 1;
- } else {
- currcons--;
- viewed = 0;
- }
- ret = -ENXIO;
- if (!vc_cons_allocated(currcons))
- goto unlock_out;
- vc = vc_cons[currcons].d;
-
- size = vcs_size(inode);
- ret = -EINVAL;
- if (pos < 0 || pos > size)
- goto unlock_out;
- if (count > size - pos)
- count = size - pos;
- written = 0;
- while (count) {
- long this_round = count;
- size_t orig_count;
- long p;
-
- if (this_round > CON_BUF_SIZE)
- this_round = CON_BUF_SIZE;
-
- /* Temporarily drop the console lock so that we can read
- * in the write data from userspace safely.
- */
- release_console_sem();
- ret = copy_from_user(con_buf, buf, this_round);
- acquire_console_sem();
-
- if (ret) {
- this_round -= ret;
- if (!this_round) {
- /* Abort loop if no data were copied. Otherwise
- * fail with -EFAULT.
- */
- if (written)
- break;
- ret = -EFAULT;
- goto unlock_out;
- }
- }
-
- /* The vcs_size might have changed while we slept to grab
- * the user buffer, so recheck.
- * Return data written up to now on failure.
- */
- size = vcs_size(inode);
- if (pos >= size)
- break;
- if (this_round > size - pos)
- this_round = size - pos;
-
- /* OK, now actually push the write to the console
- * under the lock using the local kernel buffer.
- */
-
- con_buf0 = con_buf;
- orig_count = this_round;
- maxcol = vc->vc_cols;
- p = pos;
- if (!attr) {
- org0 = org = screen_pos(vc, p, viewed);
- col = p % maxcol;
- p += maxcol - col;
-
- while (this_round > 0) {
- unsigned char c = *con_buf0++;
-
- this_round--;
- vcs_scr_writew(vc,
- (vcs_scr_readw(vc, org) & 0xff00) | c, org);
- org++;
- if (++col == maxcol) {
- org = screen_pos(vc, p, viewed);
- col = 0;
- p += maxcol;
- }
- }
- } else {
- if (p < HEADER_SIZE) {
- char header[HEADER_SIZE];
-
- getconsxy(vc, header + 2);
- while (p < HEADER_SIZE && this_round > 0) {
- this_round--;
- header[p++] = *con_buf0++;
- }
- if (!viewed)
- putconsxy(vc, header + 2);
- }
- p -= HEADER_SIZE;
- col = (p/2) % maxcol;
- if (this_round > 0) {
- org0 = org = screen_pos(vc, p/2, viewed);
- if ((p & 1) && this_round > 0) {
- char c;
-
- this_round--;
- c = *con_buf0++;
-#ifdef __BIG_ENDIAN
- vcs_scr_writew(vc, c |
- (vcs_scr_readw(vc, org) & 0xff00), org);
-#else
- vcs_scr_writew(vc, (c << 8) |
- (vcs_scr_readw(vc, org) & 0xff), org);
-#endif
- org++;
- p++;
- if (++col == maxcol) {
- org = screen_pos(vc, p/2, viewed);
- col = 0;
- }
- }
- p /= 2;
- p += maxcol - col;
- }
- while (this_round > 1) {
- unsigned short w;
-
- w = get_unaligned(((unsigned short *)con_buf0));
- vcs_scr_writew(vc, w, org++);
- con_buf0 += 2;
- this_round -= 2;
- if (++col == maxcol) {
- org = screen_pos(vc, p, viewed);
- col = 0;
- p += maxcol;
- }
- }
- if (this_round > 0) {
- unsigned char c;
-
- c = *con_buf0++;
-#ifdef __BIG_ENDIAN
- vcs_scr_writew(vc, (vcs_scr_readw(vc, org) & 0xff) | (c << 8), org);
-#else
- vcs_scr_writew(vc, (vcs_scr_readw(vc, org) & 0xff00) | c, org);
-#endif
- }
- }
- count -= orig_count;
- written += orig_count;
- buf += orig_count;
- pos += orig_count;
- if (org0)
- update_region(vc, (unsigned long)(org0), org - org0);
- }
- *ppos += written;
- ret = written;
- if (written)
- vcs_scr_updated(vc);
-
-unlock_out:
- release_console_sem();
-
- mutex_unlock(&con_buf_mtx);
-
- return ret;
-}
-
-static unsigned int
-vcs_poll(struct file *file, poll_table *wait)
-{
- struct vcs_poll_data *poll = vcs_poll_data_get(file);
- int ret = 0;
-
- if (poll) {
- poll_wait(file, &poll->waitq, wait);
- if (!poll->seen_last_update)
- ret = POLLIN | POLLRDNORM;
- }
- return ret;
-}
-
-static int
-vcs_fasync(int fd, struct file *file, int on)
-{
- struct vcs_poll_data *poll = file->private_data;
-
- if (!poll) {
- /* don't allocate anything if all we want is disable fasync */
- if (!on)
- return 0;
- poll = vcs_poll_data_get(file);
- if (!poll)
- return -ENOMEM;
- }
-
- return fasync_helper(fd, file, on, &poll->fasync);
-}
-
-static int
-vcs_open(struct inode *inode, struct file *filp)
-{
- unsigned int currcons = iminor(inode) & 127;
- int ret = 0;
-
- tty_lock();
- if(currcons && !vc_cons_allocated(currcons-1))
- ret = -ENXIO;
- tty_unlock();
- return ret;
-}
-
-static int vcs_release(struct inode *inode, struct file *file)
-{
- struct vcs_poll_data *poll = file->private_data;
-
- if (poll)
- vcs_poll_data_free(poll);
- return 0;
-}
-
-static const struct file_operations vcs_fops = {
- .llseek = vcs_lseek,
- .read = vcs_read,
- .write = vcs_write,
- .poll = vcs_poll,
- .fasync = vcs_fasync,
- .open = vcs_open,
- .release = vcs_release,
-};
-
-static struct class *vc_class;
-
-void vcs_make_sysfs(int index)
-{
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 1), NULL,
- "vcs%u", index + 1);
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 129), NULL,
- "vcsa%u", index + 1);
-}
-
-void vcs_remove_sysfs(int index)
-{
- device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 1));
- device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 129));
-}
-
-int __init vcs_init(void)
-{
- unsigned int i;
-
- if (register_chrdev(VCS_MAJOR, "vcs", &vcs_fops))
- panic("unable to get major %d for vcs device", VCS_MAJOR);
- vc_class = class_create(THIS_MODULE, "vc");
-
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 0), NULL, "vcs");
- device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 128), NULL, "vcsa");
- for (i = 0; i < MIN_NR_CONSOLES; i++)
- vcs_make_sysfs(i);
- return 0;
-}