diff options
Diffstat (limited to 'drivers/tty/vt/vc_screen.c')
-rw-r--r-- | drivers/tty/vt/vc_screen.c | 71 |
1 files changed, 45 insertions, 26 deletions
diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c index 778f83ea2249..a6813e3393ec 100644 --- a/drivers/tty/vt/vc_screen.c +++ b/drivers/tty/vt/vc_screen.c @@ -200,39 +200,47 @@ vcs_vc(struct inode *inode, int *viewed) return vc_cons[currcons].d; } -/* - * Returns size for VC carried by inode. +/** + * vcs_size -- return size for a VC in @vc + * @vc: which VC + * @attr: does it use attributes? + * @unicode: is it unicode? + * * Must be called with console_lock. */ -static int -vcs_size(struct inode *inode) +static int vcs_size(const struct vc_data *vc, bool attr, bool unicode) { int size; - struct vc_data *vc; WARN_CONSOLE_UNLOCKED(); - vc = vcs_vc(inode, NULL); - if (!vc) - return -ENXIO; - size = vc->vc_rows * vc->vc_cols; - if (use_attributes(inode)) { - if (use_unicode(inode)) + if (attr) { + if (unicode) return -EOPNOTSUPP; - size = 2*size + HEADER_SIZE; - } else if (use_unicode(inode)) + + size = 2 * size + HEADER_SIZE; + } else if (unicode) size *= 4; + return size; } static loff_t vcs_lseek(struct file *file, loff_t offset, int orig) { + struct inode *inode = file_inode(file); + struct vc_data *vc; int size; console_lock(); - size = vcs_size(file_inode(file)); + vc = vcs_vc(inode, NULL); + if (!vc) { + console_unlock(); + return -ENXIO; + } + + size = vcs_size(vc, use_attributes(inode), use_unicode(inode)); console_unlock(); if (size < 0) return size; @@ -265,10 +273,6 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) uni_mode = use_unicode(inode); attr = use_attributes(inode); - ret = -ENXIO; - vc = vcs_vc(inode, &viewed); - if (!vc) - goto unlock_out; ret = -EINVAL; if (pos < 0) @@ -288,16 +292,20 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) ssize_t orig_count; long p = pos; + vc = vcs_vc(inode, &viewed); + if (!vc) { + ret = -ENXIO; + break; + } + /* Check whether we are above size each round, * as copy_to_user at the end of this loop * could sleep. */ - size = vcs_size(inode); + size = vcs_size(vc, attr, uni_mode); if (size < 0) { - if (read) - break; ret = size; - goto unlock_out; + break; } if (pos >= size) break; @@ -476,7 +484,11 @@ vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) if (!vc) goto unlock_out; - size = vcs_size(inode); + size = vcs_size(vc, attr, false); + if (size < 0) { + ret = size; + goto unlock_out; + } ret = -EINVAL; if (pos < 0 || pos > size) goto unlock_out; @@ -511,11 +523,18 @@ vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) } } - /* The vcs_size might have changed while we slept to grab - * the user buffer, so recheck. + /* The vc might have been freed or 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); + vc = vcs_vc(inode, &viewed); + if (!vc) { + if (written) + break; + ret = -ENXIO; + goto unlock_out; + } + size = vcs_size(vc, attr, false); if (size < 0) { if (written) break; |