diff options
| author | Jan Beulich <JBeulich@novell.com> | 2006-03-25 03:07:31 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-25 08:22:55 -0800 |
| commit | c654d60e8f0ea13e35b15cff54c0e473b8b162be (patch) | |
| tree | 5c496d488666225909ab1eb7e116827cd013ae60 /drivers | |
| parent | 58bf6a2db2a4a1b41712674d9165510180259dec (diff) | |
| download | lwn-c654d60e8f0ea13e35b15cff54c0e473b8b162be.tar.gz lwn-c654d60e8f0ea13e35b15cff54c0e473b8b162be.zip | |
[PATCH] adjust /dev/{kmem,mem,port} write handlers
The /dev/mem and /dev/kmem write handlers weren't fully POSIX compliant in
that they wouldn't always force the file pointer to be updated when
returning success status.
The /dev/port write handler was inconsistent with the /dev/mem and
/dev/kmem handlers in that when encountering a -EFAULT condition after
already having written a number of items it would return -EFAULT rather
than the number of bytes written.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/char/mem.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 29c41f4418c0..26d0116b48d4 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -216,11 +216,9 @@ static ssize_t write_mem(struct file * file, const char __user * buf, copied = copy_from_user(ptr, buf, sz); if (copied) { - ssize_t ret; - - ret = written + (sz - copied); - if (ret) - return ret; + written += sz - copied; + if (written) + break; return -EFAULT; } buf += sz; @@ -456,11 +454,9 @@ do_write_kmem(void *p, unsigned long realp, const char __user * buf, copied = copy_from_user(ptr, buf, sz); if (copied) { - ssize_t ret; - - ret = written + (sz - copied); - if (ret) - return ret; + written += sz - copied; + if (written) + break; return -EFAULT; } buf += sz; @@ -514,11 +510,10 @@ static ssize_t write_kmem(struct file * file, const char __user * buf, if (len) { written = copy_from_user(kbuf, buf, len); if (written) { - ssize_t ret; - + if (wrote + virtr) + break; free_page((unsigned long)kbuf); - ret = wrote + virtr + (len - written); - return ret ? ret : -EFAULT; + return -EFAULT; } } len = vwrite(kbuf, (char *)p, len); @@ -563,8 +558,11 @@ static ssize_t write_port(struct file * file, const char __user * buf, return -EFAULT; while (count-- > 0 && i < 65536) { char c; - if (__get_user(c, tmp)) + if (__get_user(c, tmp)) { + if (tmp > buf) + break; return -EFAULT; + } outb(c,i); i++; tmp++; |