mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-19 02:04:19 +08:00
a695f16729
If user space opens a unit record device node then vmur is leaving the kernel with lock open_mutex still held to prevent other processes from opening the device simultaneously. This causes lockdep to complain about a lock held when returning to user space. Now the mutex is replaced by a wait queue to serialize device open. Signed-off-by: Frank Munzert <munzert@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
111 lines
3.0 KiB
C
111 lines
3.0 KiB
C
/*
|
|
* Linux driver for System z and s390 unit record devices
|
|
* (z/VM virtual punch, reader, printer)
|
|
*
|
|
* Copyright IBM Corp. 2001, 2007
|
|
* Authors: Malcolm Beattie <beattiem@uk.ibm.com>
|
|
* Michael Holzheu <holzheu@de.ibm.com>
|
|
* Frank Munzert <munzert@de.ibm.com>
|
|
*/
|
|
|
|
#ifndef _VMUR_H_
|
|
#define _VMUR_H_
|
|
|
|
#define DEV_CLASS_UR_I 0x20 /* diag210 unit record input device class */
|
|
#define DEV_CLASS_UR_O 0x10 /* diag210 unit record output device class */
|
|
/*
|
|
* we only support z/VM's default unit record devices:
|
|
* both in SPOOL directory control statement and in CP DEFINE statement
|
|
* RDR defaults to 2540 reader
|
|
* PUN defaults to 2540 punch
|
|
* PRT defaults to 1403 printer
|
|
*/
|
|
#define READER_PUNCH_DEVTYPE 0x2540
|
|
#define PRINTER_DEVTYPE 0x1403
|
|
|
|
/* z/VM spool file control block SFBLOK */
|
|
struct file_control_block {
|
|
char reserved_1[8];
|
|
char user_owner[8];
|
|
char user_orig[8];
|
|
__s32 data_recs;
|
|
__s16 rec_len;
|
|
__s16 file_num;
|
|
__u8 file_stat;
|
|
__u8 dev_type;
|
|
char reserved_2[6];
|
|
char file_name[12];
|
|
char file_type[12];
|
|
char create_date[8];
|
|
char create_time[8];
|
|
char reserved_3[6];
|
|
__u8 file_class;
|
|
__u8 sfb_lok;
|
|
__u64 distr_code;
|
|
__u32 reserved_4;
|
|
__u8 current_starting_copy_number;
|
|
__u8 sfblock_cntrl_flags;
|
|
__u8 reserved_5;
|
|
__u8 more_status_flags;
|
|
char rest[200];
|
|
} __attribute__ ((packed));
|
|
|
|
#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
|
|
* via the ccw_device driver model.
|
|
*/
|
|
struct urdev {
|
|
struct ccw_device *cdev; /* Backpointer to ccw device */
|
|
struct mutex io_mutex; /* Serialises device IO */
|
|
struct completion *io_done; /* do_ur_io waits; irq completes */
|
|
struct device *device;
|
|
struct cdev *char_device;
|
|
struct ccw_dev_id dev_id; /* device id */
|
|
size_t reclen; /* Record length for *write* CCWs */
|
|
int class; /* VM device class */
|
|
int io_request_rc; /* return code from I/O request */
|
|
atomic_t ref_count; /* reference counter */
|
|
wait_queue_head_t wait; /* wait queue to serialize open */
|
|
int open_flag; /* "urdev is open" flag */
|
|
spinlock_t open_lock; /* serialize critical sections */
|
|
};
|
|
|
|
/*
|
|
* A struct urfile is allocated at open() time for each device and
|
|
* freed on release().
|
|
*/
|
|
struct urfile {
|
|
struct urdev *urd;
|
|
unsigned int flags;
|
|
size_t dev_reclen;
|
|
__u16 file_reclen;
|
|
};
|
|
|
|
/*
|
|
* Device major/minor definitions.
|
|
*/
|
|
|
|
#define UR_MAJOR 0 /* get dynamic major */
|
|
/*
|
|
* We map minor numbers directly to device numbers (0-FFFF) for simplicity.
|
|
* This avoids having to allocate (and manage) slot numbers.
|
|
*/
|
|
#define NUM_MINORS 65536
|
|
|
|
/* Limiting each I/O to 511 records limits chan prog to 4KB (511 r/w + 1 NOP) */
|
|
#define MAX_RECS_PER_IO 511
|
|
#define WRITE_CCW_CMD 0x01
|
|
|
|
#define TRACE(x...) debug_sprintf_event(vmur_dbf, 1, x)
|
|
#define CCWDEV_CU_DI(cutype, di) \
|
|
CCW_DEVICE(cutype, 0x00), .driver_info = (di)
|
|
|
|
#define FILE_RECLEN_OFFSET 4064 /* reclen offset in spool data block */
|
|
|
|
#endif /* _VMUR_H_ */
|