diff options
author | Michael Holzheu <holzheu@de.ibm.com> | 2007-08-10 12:32:33 (GMT) |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2007-08-10 12:32:38 (GMT) |
commit | 4eac34529bce2b4cca9be90a6903c965baa8193c (patch) | |
tree | 2a0d04aa4ed5b9c2d9a75158c6c0715456443e5f /drivers/s390/char | |
parent | f2405598e0678e9c93dd780f2a12fc562ece3d13 (diff) | |
download | linux-4eac34529bce2b4cca9be90a6903c965baa8193c.tar.xz |
[S390] vmur: add "top of queue" sanity check for reader open
If the z/VM reader is already open, it can happen that after opening the
Linux reader device, not the topmost file is processed. According the
semantics of the Linux z/VM unit record device driver, always the topmost
file has to be processed. With this fix an error is returned if that is
not the case.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/char')
-rw-r--r-- | drivers/s390/char/vmur.c | 7 | ||||
-rw-r--r-- | drivers/s390/char/vmur.h | 1 |
2 files changed, 7 insertions, 1 deletions
diff --git a/drivers/s390/char/vmur.c b/drivers/s390/char/vmur.c index 04395c0..a9d5862 100644 --- a/drivers/s390/char/vmur.c +++ b/drivers/s390/char/vmur.c @@ -565,9 +565,14 @@ static int verify_device(struct urdev *urd) return -ENOMEM; rc = diag_read_file(urd->dev_id.devno, buf); kfree(buf); - if ((rc != 0) && (rc != -ENODATA)) /* EOF does not hurt */ return rc; + /* check if the file on top of the queue is open now */ + rc = diag_read_next_file_info(&fcb, 0); + if (rc) + return rc; + if (!(fcb.file_stat & FLG_IN_USE)) + return -EMFILE; return 0; default: return -ENOTSUPP; diff --git a/drivers/s390/char/vmur.h b/drivers/s390/char/vmur.h index 522a9df..2b3c564 100644 --- a/drivers/s390/char/vmur.h +++ b/drivers/s390/char/vmur.h @@ -53,6 +53,7 @@ struct file_control_block { #define FLG_SYSTEM_HOLD 0x04 #define FLG_CP_DUMP 0x10 #define FLG_USER_HOLD 0x20 +#define FLG_IN_USE 0x80 /* * A struct urdev is created for each ur device that is made available |