diff options
| author | Vitaly Mayatskikh <v.mayatskih@gmail.com> | 2008-09-28 23:24:33 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-10-07 14:26:21 +1100 |
| commit | 76c31f239ea221a6c84bd26141262a43bfe8b7f4 (patch) | |
| tree | e93025a86c4c935d14a996b17aae572b9ded49dd | |
| parent | 3396c72b92efd16bca16490a72277b3a494e0f0e (diff) | |
powerpc: Honor O_NONBLOCK flag when reading RTAS log
rtas_log_read() doesn't check file flags for O_NONBLOCK and blocks
non-blocking readers of /proc/ppc64/rtas/error_log when there is
no data available. This fixes it.
Also rtas_log_read() returns now with ENODATA to prevent suspending of
process in wait_event_interruptible() when logging facility was
switched off and log is already empty.
Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/platforms/pseries/rtasd.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/arch/powerpc/platforms/pseries/rtasd.c b/arch/powerpc/platforms/pseries/rtasd.c index c9ffd8c225f..f4e55be2eea 100644 --- a/arch/powerpc/platforms/pseries/rtasd.c +++ b/arch/powerpc/platforms/pseries/rtasd.c @@ -295,19 +295,29 @@ static ssize_t rtas_log_read(struct file * file, char __user * buf, if (!tmp) return -ENOMEM; - spin_lock_irqsave(&rtasd_log_lock, s); /* if it's 0, then we know we got the last one (the one in NVRAM) */ - if (rtas_log_size == 0 && logging_enabled) - nvram_clear_error_log(); - spin_unlock_irqrestore(&rtasd_log_lock, s); + while (rtas_log_size == 0) { + if (file->f_flags & O_NONBLOCK) { + spin_unlock_irqrestore(&rtasd_log_lock, s); + error = -EAGAIN; + goto out; + } + if (!logging_enabled) { + spin_unlock_irqrestore(&rtasd_log_lock, s); + error = -ENODATA; + goto out; + } + nvram_clear_error_log(); - error = wait_event_interruptible(rtas_log_wait, rtas_log_size); - if (error) - goto out; + spin_unlock_irqrestore(&rtasd_log_lock, s); + error = wait_event_interruptible(rtas_log_wait, rtas_log_size); + if (error) + goto out; + spin_lock_irqsave(&rtasd_log_lock, s); + } - spin_lock_irqsave(&rtasd_log_lock, s); offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK); memcpy(tmp, &rtas_log_buf[offset], count); |