This patch is based on the "misc" branch of the SCSI tree and the 5-patch series for st sent by Jeff Mahoney 8/18/2012 and Ack-ed by Kai on 8/20.
From: Jeff Mahoney <[email protected]> The st_mutex was created when the BKL was removed, and prevents simultaneous st_open calls. It is better to protect just the necessary data. Signed-off-by: Jeff Mahoney <[email protected]> Reviewed-by: Lee Duncan <[email protected]> --- drivers/scsi/st.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index ceca095..98156a9 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -75,7 +75,6 @@ static const char *verstr = "20101219"; #include "st_options.h" #include "st.h" -static DEFINE_MUTEX(st_mutex); static int buffer_kbs; static int max_sg_segs; static int try_direct_io = TRY_DIRECT_IO; @@ -1185,7 +1184,6 @@ static int st_open(struct inode *inode, struct file *filp) int dev = TAPE_NR(inode); char *name; - mutex_lock(&st_mutex); /* * We really want to do nonseekable_open(inode, filp); here, but some * versions of tar incorrectly call lseek on tapes and bail out if that @@ -1194,7 +1192,6 @@ static int st_open(struct inode *inode, struct file *filp) filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); if (!(STp = scsi_tape_get(dev))) { - mutex_unlock(&st_mutex); return -ENXIO; } @@ -1205,7 +1202,6 @@ static int st_open(struct inode *inode, struct file *filp) if (STp->in_use) { spin_unlock(&st_use_lock); scsi_tape_put(STp); - mutex_unlock(&st_mutex); DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); ) return (-EBUSY); } @@ -1259,16 +1255,16 @@ static int st_open(struct inode *inode, struct file *filp) retval = (-EIO); goto err_out; } - mutex_unlock(&st_mutex); return 0; err_out: normalize_buffer(STp->buffer); + spin_lock(&st_use_lock); STp->in_use = 0; + spin_unlock(&st_use_lock); scsi_tape_put(STp); if (resumed) scsi_autopm_put_device(STp->device); - mutex_unlock(&st_mutex); return retval; } -- 1.7.11.5 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
