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1034 lines
23 KiB
1034 lines
23 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Linux driver for System z and s390 unit record devices |
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* (z/VM virtual punch, reader, printer) |
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* |
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* Copyright IBM Corp. 2001, 2009 |
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* Authors: Malcolm Beattie <[email protected]> |
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* Michael Holzheu <[email protected]> |
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* Frank Munzert <[email protected]> |
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*/ |
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|
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#define KMSG_COMPONENT "vmur" |
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
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|
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#include <linux/cdev.h> |
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#include <linux/slab.h> |
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#include <linux/module.h> |
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|
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#include <linux/uaccess.h> |
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#include <asm/cio.h> |
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#include <asm/ccwdev.h> |
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#include <asm/debug.h> |
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#include <asm/diag.h> |
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|
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#include "vmur.h" |
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|
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/* |
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* Driver overview |
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* |
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* Unit record device support is implemented as a character device driver. |
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* We can fit at least 16 bits into a device minor number and use the |
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* simple method of mapping a character device number with minor abcd |
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* to the unit record device with devno abcd. |
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* I/O to virtual unit record devices is handled as follows: |
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* Reads: Diagnose code 0x14 (input spool file manipulation) |
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* is used to read spool data page-wise. |
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* Writes: The CCW used is WRITE_CCW_CMD (0x01). The device's record length |
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* is available by reading sysfs attr reclen. Each write() to the device |
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* must specify an integral multiple (maximal 511) of reclen. |
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*/ |
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|
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static char ur_banner[] = "z/VM virtual unit record device driver"; |
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|
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MODULE_AUTHOR("IBM Corporation"); |
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MODULE_DESCRIPTION("s390 z/VM virtual unit record device driver"); |
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MODULE_LICENSE("GPL"); |
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|
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static dev_t ur_first_dev_maj_min; |
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static struct class *vmur_class; |
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static struct debug_info *vmur_dbf; |
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|
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/* We put the device's record length (for writes) in the driver_info field */ |
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static struct ccw_device_id ur_ids[] = { |
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{ CCWDEV_CU_DI(READER_PUNCH_DEVTYPE, 80) }, |
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{ CCWDEV_CU_DI(PRINTER_DEVTYPE, 132) }, |
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{ /* end of list */ } |
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}; |
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|
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MODULE_DEVICE_TABLE(ccw, ur_ids); |
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|
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static int ur_probe(struct ccw_device *cdev); |
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static void ur_remove(struct ccw_device *cdev); |
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static int ur_set_online(struct ccw_device *cdev); |
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static int ur_set_offline(struct ccw_device *cdev); |
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|
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static struct ccw_driver ur_driver = { |
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.driver = { |
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.name = "vmur", |
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.owner = THIS_MODULE, |
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}, |
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.ids = ur_ids, |
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.probe = ur_probe, |
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.remove = ur_remove, |
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.set_online = ur_set_online, |
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.set_offline = ur_set_offline, |
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.int_class = IRQIO_VMR, |
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}; |
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|
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static DEFINE_MUTEX(vmur_mutex); |
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|
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/* |
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* Allocation, freeing, getting and putting of urdev structures |
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* |
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* Each ur device (urd) contains a reference to its corresponding ccw device |
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* (cdev) using the urd->cdev pointer. Each ccw device has a reference to the |
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* ur device using dev_get_drvdata(&cdev->dev) pointer. |
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* |
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* urd references: |
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* - ur_probe gets a urd reference, ur_remove drops the reference |
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* dev_get_drvdata(&cdev->dev) |
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* - ur_open gets a urd reference, ur_release drops the reference |
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* (urf->urd) |
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* |
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* cdev references: |
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* - urdev_alloc get a cdev reference (urd->cdev) |
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* - urdev_free drops the cdev reference (urd->cdev) |
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* |
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* Setting and clearing of dev_get_drvdata(&cdev->dev) is protected by the ccwdev lock |
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*/ |
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static struct urdev *urdev_alloc(struct ccw_device *cdev) |
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{ |
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struct urdev *urd; |
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|
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urd = kzalloc(sizeof(struct urdev), GFP_KERNEL); |
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if (!urd) |
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return NULL; |
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urd->reclen = cdev->id.driver_info; |
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ccw_device_get_id(cdev, &urd->dev_id); |
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mutex_init(&urd->io_mutex); |
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init_waitqueue_head(&urd->wait); |
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spin_lock_init(&urd->open_lock); |
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refcount_set(&urd->ref_count, 1); |
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urd->cdev = cdev; |
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get_device(&cdev->dev); |
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return urd; |
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} |
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|
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static void urdev_free(struct urdev *urd) |
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{ |
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TRACE("urdev_free: %p\n", urd); |
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if (urd->cdev) |
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put_device(&urd->cdev->dev); |
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kfree(urd); |
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} |
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|
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static void urdev_get(struct urdev *urd) |
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{ |
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refcount_inc(&urd->ref_count); |
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} |
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|
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static struct urdev *urdev_get_from_cdev(struct ccw_device *cdev) |
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{ |
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struct urdev *urd; |
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unsigned long flags; |
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|
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spin_lock_irqsave(get_ccwdev_lock(cdev), flags); |
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urd = dev_get_drvdata(&cdev->dev); |
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if (urd) |
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urdev_get(urd); |
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spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags); |
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return urd; |
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} |
|
|
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static struct urdev *urdev_get_from_devno(u16 devno) |
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{ |
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char bus_id[16]; |
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struct ccw_device *cdev; |
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struct urdev *urd; |
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|
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sprintf(bus_id, "0.0.%04x", devno); |
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cdev = get_ccwdev_by_busid(&ur_driver, bus_id); |
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if (!cdev) |
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return NULL; |
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urd = urdev_get_from_cdev(cdev); |
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put_device(&cdev->dev); |
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return urd; |
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} |
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|
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static void urdev_put(struct urdev *urd) |
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{ |
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if (refcount_dec_and_test(&urd->ref_count)) |
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urdev_free(urd); |
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} |
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|
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/* |
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* Low-level functions to do I/O to a ur device. |
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* alloc_chan_prog |
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* free_chan_prog |
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* do_ur_io |
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* ur_int_handler |
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* |
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* alloc_chan_prog allocates and builds the channel program |
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* free_chan_prog frees memory of the channel program |
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* |
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* do_ur_io issues the channel program to the device and blocks waiting |
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* on a completion event it publishes at urd->io_done. The function |
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* serialises itself on the device's mutex so that only one I/O |
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* is issued at a time (and that I/O is synchronous). |
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* |
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* ur_int_handler catches the "I/O done" interrupt, writes the |
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* subchannel status word into the scsw member of the urdev structure |
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* and complete()s the io_done to wake the waiting do_ur_io. |
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* |
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* The caller of do_ur_io is responsible for kfree()ing the channel program |
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* address pointer that alloc_chan_prog returned. |
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*/ |
|
|
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static void free_chan_prog(struct ccw1 *cpa) |
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{ |
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struct ccw1 *ptr = cpa; |
|
|
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while (ptr->cda) { |
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kfree((void *)(addr_t) ptr->cda); |
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ptr++; |
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} |
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kfree(cpa); |
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} |
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|
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/* |
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* alloc_chan_prog |
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* The channel program we use is write commands chained together |
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* with a final NOP CCW command-chained on (which ensures that CE and DE |
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* are presented together in a single interrupt instead of as separate |
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* interrupts unless an incorrect length indication kicks in first). The |
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* data length in each CCW is reclen. |
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*/ |
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static struct ccw1 *alloc_chan_prog(const char __user *ubuf, int rec_count, |
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int reclen) |
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{ |
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struct ccw1 *cpa; |
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void *kbuf; |
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int i; |
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|
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TRACE("alloc_chan_prog(%p, %i, %i)\n", ubuf, rec_count, reclen); |
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|
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/* |
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* We chain a NOP onto the writes to force CE+DE together. |
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* That means we allocate room for CCWs to cover count/reclen |
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* records plus a NOP. |
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*/ |
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cpa = kcalloc(rec_count + 1, sizeof(struct ccw1), |
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GFP_KERNEL | GFP_DMA); |
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if (!cpa) |
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return ERR_PTR(-ENOMEM); |
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|
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for (i = 0; i < rec_count; i++) { |
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cpa[i].cmd_code = WRITE_CCW_CMD; |
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cpa[i].flags = CCW_FLAG_CC | CCW_FLAG_SLI; |
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cpa[i].count = reclen; |
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kbuf = kmalloc(reclen, GFP_KERNEL | GFP_DMA); |
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if (!kbuf) { |
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free_chan_prog(cpa); |
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return ERR_PTR(-ENOMEM); |
|
} |
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cpa[i].cda = (u32)(addr_t) kbuf; |
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if (copy_from_user(kbuf, ubuf, reclen)) { |
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free_chan_prog(cpa); |
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return ERR_PTR(-EFAULT); |
|
} |
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ubuf += reclen; |
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} |
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/* The following NOP CCW forces CE+DE to be presented together */ |
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cpa[i].cmd_code = CCW_CMD_NOOP; |
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return cpa; |
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} |
|
|
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static int do_ur_io(struct urdev *urd, struct ccw1 *cpa) |
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{ |
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int rc; |
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struct ccw_device *cdev = urd->cdev; |
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DECLARE_COMPLETION_ONSTACK(event); |
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|
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TRACE("do_ur_io: cpa=%p\n", cpa); |
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|
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rc = mutex_lock_interruptible(&urd->io_mutex); |
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if (rc) |
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return rc; |
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|
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urd->io_done = &event; |
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|
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spin_lock_irq(get_ccwdev_lock(cdev)); |
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rc = ccw_device_start(cdev, cpa, 1, 0, 0); |
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spin_unlock_irq(get_ccwdev_lock(cdev)); |
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|
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TRACE("do_ur_io: ccw_device_start returned %d\n", rc); |
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if (rc) |
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goto out; |
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|
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wait_for_completion(&event); |
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TRACE("do_ur_io: I/O complete\n"); |
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rc = 0; |
|
|
|
out: |
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mutex_unlock(&urd->io_mutex); |
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return rc; |
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} |
|
|
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/* |
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* ur interrupt handler, called from the ccw_device layer |
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*/ |
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static void ur_int_handler(struct ccw_device *cdev, unsigned long intparm, |
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struct irb *irb) |
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{ |
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struct urdev *urd; |
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|
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if (!IS_ERR(irb)) { |
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TRACE("ur_int_handler: intparm=0x%lx cstat=%02x dstat=%02x res=%u\n", |
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intparm, irb->scsw.cmd.cstat, irb->scsw.cmd.dstat, |
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irb->scsw.cmd.count); |
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} |
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if (!intparm) { |
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TRACE("ur_int_handler: unsolicited interrupt\n"); |
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return; |
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} |
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urd = dev_get_drvdata(&cdev->dev); |
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BUG_ON(!urd); |
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/* On special conditions irb is an error pointer */ |
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if (IS_ERR(irb)) |
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urd->io_request_rc = PTR_ERR(irb); |
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else if (irb->scsw.cmd.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END)) |
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urd->io_request_rc = 0; |
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else |
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urd->io_request_rc = -EIO; |
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|
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complete(urd->io_done); |
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} |
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|
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/* |
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* reclen sysfs attribute - The record length to be used for write CCWs |
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*/ |
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static ssize_t ur_attr_reclen_show(struct device *dev, |
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struct device_attribute *attr, char *buf) |
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{ |
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struct urdev *urd; |
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int rc; |
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|
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urd = urdev_get_from_cdev(to_ccwdev(dev)); |
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if (!urd) |
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return -ENODEV; |
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rc = sprintf(buf, "%zu\n", urd->reclen); |
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urdev_put(urd); |
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return rc; |
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} |
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|
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static DEVICE_ATTR(reclen, 0444, ur_attr_reclen_show, NULL); |
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|
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static int ur_create_attributes(struct device *dev) |
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{ |
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return device_create_file(dev, &dev_attr_reclen); |
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} |
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|
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static void ur_remove_attributes(struct device *dev) |
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{ |
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device_remove_file(dev, &dev_attr_reclen); |
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} |
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|
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/* |
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* diagnose code 0x210 - retrieve device information |
|
* cc=0 normal completion, we have a real device |
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* cc=1 CP paging error |
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* cc=2 The virtual device exists, but is not associated with a real device |
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* cc=3 Invalid device address, or the virtual device does not exist |
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*/ |
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static int get_urd_class(struct urdev *urd) |
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{ |
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static struct diag210 ur_diag210; |
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int cc; |
|
|
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ur_diag210.vrdcdvno = urd->dev_id.devno; |
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ur_diag210.vrdclen = sizeof(struct diag210); |
|
|
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cc = diag210(&ur_diag210); |
|
switch (cc) { |
|
case 0: |
|
return -EOPNOTSUPP; |
|
case 2: |
|
return ur_diag210.vrdcvcla; /* virtual device class */ |
|
case 3: |
|
return -ENODEV; |
|
default: |
|
return -EIO; |
|
} |
|
} |
|
|
|
/* |
|
* Allocation and freeing of urfile structures |
|
*/ |
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static struct urfile *urfile_alloc(struct urdev *urd) |
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{ |
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struct urfile *urf; |
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|
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urf = kzalloc(sizeof(struct urfile), GFP_KERNEL); |
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if (!urf) |
|
return NULL; |
|
urf->urd = urd; |
|
|
|
TRACE("urfile_alloc: urd=%p urf=%p rl=%zu\n", urd, urf, |
|
urf->dev_reclen); |
|
|
|
return urf; |
|
} |
|
|
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static void urfile_free(struct urfile *urf) |
|
{ |
|
TRACE("urfile_free: urf=%p urd=%p\n", urf, urf->urd); |
|
kfree(urf); |
|
} |
|
|
|
/* |
|
* The fops implementation of the character device driver |
|
*/ |
|
static ssize_t do_write(struct urdev *urd, const char __user *udata, |
|
size_t count, size_t reclen, loff_t *ppos) |
|
{ |
|
struct ccw1 *cpa; |
|
int rc; |
|
|
|
cpa = alloc_chan_prog(udata, count / reclen, reclen); |
|
if (IS_ERR(cpa)) |
|
return PTR_ERR(cpa); |
|
|
|
rc = do_ur_io(urd, cpa); |
|
if (rc) |
|
goto fail_kfree_cpa; |
|
|
|
if (urd->io_request_rc) { |
|
rc = urd->io_request_rc; |
|
goto fail_kfree_cpa; |
|
} |
|
*ppos += count; |
|
rc = count; |
|
|
|
fail_kfree_cpa: |
|
free_chan_prog(cpa); |
|
return rc; |
|
} |
|
|
|
static ssize_t ur_write(struct file *file, const char __user *udata, |
|
size_t count, loff_t *ppos) |
|
{ |
|
struct urfile *urf = file->private_data; |
|
|
|
TRACE("ur_write: count=%zu\n", count); |
|
|
|
if (count == 0) |
|
return 0; |
|
|
|
if (count % urf->dev_reclen) |
|
return -EINVAL; /* count must be a multiple of reclen */ |
|
|
|
if (count > urf->dev_reclen * MAX_RECS_PER_IO) |
|
count = urf->dev_reclen * MAX_RECS_PER_IO; |
|
|
|
return do_write(urf->urd, udata, count, urf->dev_reclen, ppos); |
|
} |
|
|
|
/* |
|
* diagnose code 0x14 subcode 0x0028 - position spool file to designated |
|
* record |
|
* cc=0 normal completion |
|
* cc=2 no file active on the virtual reader or device not ready |
|
* cc=3 record specified is beyond EOF |
|
*/ |
|
static int diag_position_to_record(int devno, int record) |
|
{ |
|
int cc; |
|
|
|
cc = diag14(record, devno, 0x28); |
|
switch (cc) { |
|
case 0: |
|
return 0; |
|
case 2: |
|
return -ENOMEDIUM; |
|
case 3: |
|
return -ENODATA; /* position beyond end of file */ |
|
default: |
|
return -EIO; |
|
} |
|
} |
|
|
|
/* |
|
* diagnose code 0x14 subcode 0x0000 - read next spool file buffer |
|
* cc=0 normal completion |
|
* cc=1 EOF reached |
|
* cc=2 no file active on the virtual reader, and no file eligible |
|
* cc=3 file already active on the virtual reader or specified virtual |
|
* reader does not exist or is not a reader |
|
*/ |
|
static int diag_read_file(int devno, char *buf) |
|
{ |
|
int cc; |
|
|
|
cc = diag14((unsigned long) buf, devno, 0x00); |
|
switch (cc) { |
|
case 0: |
|
return 0; |
|
case 1: |
|
return -ENODATA; |
|
case 2: |
|
return -ENOMEDIUM; |
|
default: |
|
return -EIO; |
|
} |
|
} |
|
|
|
static ssize_t diag14_read(struct file *file, char __user *ubuf, size_t count, |
|
loff_t *offs) |
|
{ |
|
size_t len, copied, res; |
|
char *buf; |
|
int rc; |
|
u16 reclen; |
|
struct urdev *urd; |
|
|
|
urd = ((struct urfile *) file->private_data)->urd; |
|
reclen = ((struct urfile *) file->private_data)->file_reclen; |
|
|
|
rc = diag_position_to_record(urd->dev_id.devno, *offs / PAGE_SIZE + 1); |
|
if (rc == -ENODATA) |
|
return 0; |
|
if (rc) |
|
return rc; |
|
|
|
len = min((size_t) PAGE_SIZE, count); |
|
buf = (char *) __get_free_page(GFP_KERNEL | GFP_DMA); |
|
if (!buf) |
|
return -ENOMEM; |
|
|
|
copied = 0; |
|
res = (size_t) (*offs % PAGE_SIZE); |
|
do { |
|
rc = diag_read_file(urd->dev_id.devno, buf); |
|
if (rc == -ENODATA) { |
|
break; |
|
} |
|
if (rc) |
|
goto fail; |
|
if (reclen && (copied == 0) && (*offs < PAGE_SIZE)) |
|
*((u16 *) &buf[FILE_RECLEN_OFFSET]) = reclen; |
|
len = min(count - copied, PAGE_SIZE - res); |
|
if (copy_to_user(ubuf + copied, buf + res, len)) { |
|
rc = -EFAULT; |
|
goto fail; |
|
} |
|
res = 0; |
|
copied += len; |
|
} while (copied != count); |
|
|
|
*offs += copied; |
|
rc = copied; |
|
fail: |
|
free_page((unsigned long) buf); |
|
return rc; |
|
} |
|
|
|
static ssize_t ur_read(struct file *file, char __user *ubuf, size_t count, |
|
loff_t *offs) |
|
{ |
|
struct urdev *urd; |
|
int rc; |
|
|
|
TRACE("ur_read: count=%zu ppos=%li\n", count, (unsigned long) *offs); |
|
|
|
if (count == 0) |
|
return 0; |
|
|
|
urd = ((struct urfile *) file->private_data)->urd; |
|
rc = mutex_lock_interruptible(&urd->io_mutex); |
|
if (rc) |
|
return rc; |
|
rc = diag14_read(file, ubuf, count, offs); |
|
mutex_unlock(&urd->io_mutex); |
|
return rc; |
|
} |
|
|
|
/* |
|
* diagnose code 0x14 subcode 0x0fff - retrieve next file descriptor |
|
* cc=0 normal completion |
|
* cc=1 no files on reader queue or no subsequent file |
|
* cc=2 spid specified is invalid |
|
*/ |
|
static int diag_read_next_file_info(struct file_control_block *buf, int spid) |
|
{ |
|
int cc; |
|
|
|
cc = diag14((unsigned long) buf, spid, 0xfff); |
|
switch (cc) { |
|
case 0: |
|
return 0; |
|
default: |
|
return -ENODATA; |
|
} |
|
} |
|
|
|
static int verify_uri_device(struct urdev *urd) |
|
{ |
|
struct file_control_block *fcb; |
|
char *buf; |
|
int rc; |
|
|
|
fcb = kmalloc(sizeof(*fcb), GFP_KERNEL | GFP_DMA); |
|
if (!fcb) |
|
return -ENOMEM; |
|
|
|
/* check for empty reader device (beginning of chain) */ |
|
rc = diag_read_next_file_info(fcb, 0); |
|
if (rc) |
|
goto fail_free_fcb; |
|
|
|
/* if file is in hold status, we do not read it */ |
|
if (fcb->file_stat & (FLG_SYSTEM_HOLD | FLG_USER_HOLD)) { |
|
rc = -EPERM; |
|
goto fail_free_fcb; |
|
} |
|
|
|
/* open file on virtual reader */ |
|
buf = (char *) __get_free_page(GFP_KERNEL | GFP_DMA); |
|
if (!buf) { |
|
rc = -ENOMEM; |
|
goto fail_free_fcb; |
|
} |
|
rc = diag_read_file(urd->dev_id.devno, buf); |
|
if ((rc != 0) && (rc != -ENODATA)) /* EOF does not hurt */ |
|
goto fail_free_buf; |
|
|
|
/* check if the file on top of the queue is open now */ |
|
rc = diag_read_next_file_info(fcb, 0); |
|
if (rc) |
|
goto fail_free_buf; |
|
if (!(fcb->file_stat & FLG_IN_USE)) { |
|
rc = -EMFILE; |
|
goto fail_free_buf; |
|
} |
|
rc = 0; |
|
|
|
fail_free_buf: |
|
free_page((unsigned long) buf); |
|
fail_free_fcb: |
|
kfree(fcb); |
|
return rc; |
|
} |
|
|
|
static int verify_device(struct urdev *urd) |
|
{ |
|
switch (urd->class) { |
|
case DEV_CLASS_UR_O: |
|
return 0; /* no check needed here */ |
|
case DEV_CLASS_UR_I: |
|
return verify_uri_device(urd); |
|
default: |
|
return -EOPNOTSUPP; |
|
} |
|
} |
|
|
|
static int get_uri_file_reclen(struct urdev *urd) |
|
{ |
|
struct file_control_block *fcb; |
|
int rc; |
|
|
|
fcb = kmalloc(sizeof(*fcb), GFP_KERNEL | GFP_DMA); |
|
if (!fcb) |
|
return -ENOMEM; |
|
rc = diag_read_next_file_info(fcb, 0); |
|
if (rc) |
|
goto fail_free; |
|
if (fcb->file_stat & FLG_CP_DUMP) |
|
rc = 0; |
|
else |
|
rc = fcb->rec_len; |
|
|
|
fail_free: |
|
kfree(fcb); |
|
return rc; |
|
} |
|
|
|
static int get_file_reclen(struct urdev *urd) |
|
{ |
|
switch (urd->class) { |
|
case DEV_CLASS_UR_O: |
|
return 0; |
|
case DEV_CLASS_UR_I: |
|
return get_uri_file_reclen(urd); |
|
default: |
|
return -EOPNOTSUPP; |
|
} |
|
} |
|
|
|
static int ur_open(struct inode *inode, struct file *file) |
|
{ |
|
u16 devno; |
|
struct urdev *urd; |
|
struct urfile *urf; |
|
unsigned short accmode; |
|
int rc; |
|
|
|
accmode = file->f_flags & O_ACCMODE; |
|
|
|
if (accmode == O_RDWR) |
|
return -EACCES; |
|
/* |
|
* We treat the minor number as the devno of the ur device |
|
* to find in the driver tree. |
|
*/ |
|
devno = iminor(file_inode(file)); |
|
|
|
urd = urdev_get_from_devno(devno); |
|
if (!urd) { |
|
rc = -ENXIO; |
|
goto out; |
|
} |
|
|
|
spin_lock(&urd->open_lock); |
|
while (urd->open_flag) { |
|
spin_unlock(&urd->open_lock); |
|
if (file->f_flags & O_NONBLOCK) { |
|
rc = -EBUSY; |
|
goto fail_put; |
|
} |
|
if (wait_event_interruptible(urd->wait, urd->open_flag == 0)) { |
|
rc = -ERESTARTSYS; |
|
goto fail_put; |
|
} |
|
spin_lock(&urd->open_lock); |
|
} |
|
urd->open_flag++; |
|
spin_unlock(&urd->open_lock); |
|
|
|
TRACE("ur_open\n"); |
|
|
|
if (((accmode == O_RDONLY) && (urd->class != DEV_CLASS_UR_I)) || |
|
((accmode == O_WRONLY) && (urd->class != DEV_CLASS_UR_O))) { |
|
TRACE("ur_open: unsupported dev class (%d)\n", urd->class); |
|
rc = -EACCES; |
|
goto fail_unlock; |
|
} |
|
|
|
rc = verify_device(urd); |
|
if (rc) |
|
goto fail_unlock; |
|
|
|
urf = urfile_alloc(urd); |
|
if (!urf) { |
|
rc = -ENOMEM; |
|
goto fail_unlock; |
|
} |
|
|
|
urf->dev_reclen = urd->reclen; |
|
rc = get_file_reclen(urd); |
|
if (rc < 0) |
|
goto fail_urfile_free; |
|
urf->file_reclen = rc; |
|
file->private_data = urf; |
|
return 0; |
|
|
|
fail_urfile_free: |
|
urfile_free(urf); |
|
fail_unlock: |
|
spin_lock(&urd->open_lock); |
|
urd->open_flag--; |
|
spin_unlock(&urd->open_lock); |
|
fail_put: |
|
urdev_put(urd); |
|
out: |
|
return rc; |
|
} |
|
|
|
static int ur_release(struct inode *inode, struct file *file) |
|
{ |
|
struct urfile *urf = file->private_data; |
|
|
|
TRACE("ur_release\n"); |
|
spin_lock(&urf->urd->open_lock); |
|
urf->urd->open_flag--; |
|
spin_unlock(&urf->urd->open_lock); |
|
wake_up_interruptible(&urf->urd->wait); |
|
urdev_put(urf->urd); |
|
urfile_free(urf); |
|
return 0; |
|
} |
|
|
|
static loff_t ur_llseek(struct file *file, loff_t offset, int whence) |
|
{ |
|
if ((file->f_flags & O_ACCMODE) != O_RDONLY) |
|
return -ESPIPE; /* seek allowed only for reader */ |
|
if (offset % PAGE_SIZE) |
|
return -ESPIPE; /* only multiples of 4K allowed */ |
|
return no_seek_end_llseek(file, offset, whence); |
|
} |
|
|
|
static const struct file_operations ur_fops = { |
|
.owner = THIS_MODULE, |
|
.open = ur_open, |
|
.release = ur_release, |
|
.read = ur_read, |
|
.write = ur_write, |
|
.llseek = ur_llseek, |
|
}; |
|
|
|
/* |
|
* ccw_device infrastructure: |
|
* ur_probe creates the struct urdev (with refcount = 1), the device |
|
* attributes, sets up the interrupt handler and validates the virtual |
|
* unit record device. |
|
* ur_remove removes the device attributes and drops the reference to |
|
* struct urdev. |
|
* |
|
* ur_probe, ur_remove, ur_set_online and ur_set_offline are serialized |
|
* by the vmur_mutex lock. |
|
* |
|
* urd->char_device is used as indication that the online function has |
|
* been completed successfully. |
|
*/ |
|
static int ur_probe(struct ccw_device *cdev) |
|
{ |
|
struct urdev *urd; |
|
int rc; |
|
|
|
TRACE("ur_probe: cdev=%p\n", cdev); |
|
|
|
mutex_lock(&vmur_mutex); |
|
urd = urdev_alloc(cdev); |
|
if (!urd) { |
|
rc = -ENOMEM; |
|
goto fail_unlock; |
|
} |
|
|
|
rc = ur_create_attributes(&cdev->dev); |
|
if (rc) { |
|
rc = -ENOMEM; |
|
goto fail_urdev_put; |
|
} |
|
cdev->handler = ur_int_handler; |
|
|
|
/* validate virtual unit record device */ |
|
urd->class = get_urd_class(urd); |
|
if (urd->class < 0) { |
|
rc = urd->class; |
|
goto fail_remove_attr; |
|
} |
|
if ((urd->class != DEV_CLASS_UR_I) && (urd->class != DEV_CLASS_UR_O)) { |
|
rc = -EOPNOTSUPP; |
|
goto fail_remove_attr; |
|
} |
|
spin_lock_irq(get_ccwdev_lock(cdev)); |
|
dev_set_drvdata(&cdev->dev, urd); |
|
spin_unlock_irq(get_ccwdev_lock(cdev)); |
|
|
|
mutex_unlock(&vmur_mutex); |
|
return 0; |
|
|
|
fail_remove_attr: |
|
ur_remove_attributes(&cdev->dev); |
|
fail_urdev_put: |
|
urdev_put(urd); |
|
fail_unlock: |
|
mutex_unlock(&vmur_mutex); |
|
return rc; |
|
} |
|
|
|
static int ur_set_online(struct ccw_device *cdev) |
|
{ |
|
struct urdev *urd; |
|
int minor, major, rc; |
|
char node_id[16]; |
|
|
|
TRACE("ur_set_online: cdev=%p\n", cdev); |
|
|
|
mutex_lock(&vmur_mutex); |
|
urd = urdev_get_from_cdev(cdev); |
|
if (!urd) { |
|
/* ur_remove already deleted our urd */ |
|
rc = -ENODEV; |
|
goto fail_unlock; |
|
} |
|
|
|
if (urd->char_device) { |
|
/* Another ur_set_online was faster */ |
|
rc = -EBUSY; |
|
goto fail_urdev_put; |
|
} |
|
|
|
minor = urd->dev_id.devno; |
|
major = MAJOR(ur_first_dev_maj_min); |
|
|
|
urd->char_device = cdev_alloc(); |
|
if (!urd->char_device) { |
|
rc = -ENOMEM; |
|
goto fail_urdev_put; |
|
} |
|
|
|
urd->char_device->ops = &ur_fops; |
|
urd->char_device->owner = ur_fops.owner; |
|
|
|
rc = cdev_add(urd->char_device, MKDEV(major, minor), 1); |
|
if (rc) |
|
goto fail_free_cdev; |
|
if (urd->cdev->id.cu_type == READER_PUNCH_DEVTYPE) { |
|
if (urd->class == DEV_CLASS_UR_I) |
|
sprintf(node_id, "vmrdr-%s", dev_name(&cdev->dev)); |
|
if (urd->class == DEV_CLASS_UR_O) |
|
sprintf(node_id, "vmpun-%s", dev_name(&cdev->dev)); |
|
} else if (urd->cdev->id.cu_type == PRINTER_DEVTYPE) { |
|
sprintf(node_id, "vmprt-%s", dev_name(&cdev->dev)); |
|
} else { |
|
rc = -EOPNOTSUPP; |
|
goto fail_free_cdev; |
|
} |
|
|
|
urd->device = device_create(vmur_class, &cdev->dev, |
|
urd->char_device->dev, NULL, "%s", node_id); |
|
if (IS_ERR(urd->device)) { |
|
rc = PTR_ERR(urd->device); |
|
TRACE("ur_set_online: device_create rc=%d\n", rc); |
|
goto fail_free_cdev; |
|
} |
|
urdev_put(urd); |
|
mutex_unlock(&vmur_mutex); |
|
return 0; |
|
|
|
fail_free_cdev: |
|
cdev_del(urd->char_device); |
|
urd->char_device = NULL; |
|
fail_urdev_put: |
|
urdev_put(urd); |
|
fail_unlock: |
|
mutex_unlock(&vmur_mutex); |
|
return rc; |
|
} |
|
|
|
static int ur_set_offline_force(struct ccw_device *cdev, int force) |
|
{ |
|
struct urdev *urd; |
|
int rc; |
|
|
|
TRACE("ur_set_offline: cdev=%p\n", cdev); |
|
urd = urdev_get_from_cdev(cdev); |
|
if (!urd) |
|
/* ur_remove already deleted our urd */ |
|
return -ENODEV; |
|
if (!urd->char_device) { |
|
/* Another ur_set_offline was faster */ |
|
rc = -EBUSY; |
|
goto fail_urdev_put; |
|
} |
|
if (!force && (refcount_read(&urd->ref_count) > 2)) { |
|
/* There is still a user of urd (e.g. ur_open) */ |
|
TRACE("ur_set_offline: BUSY\n"); |
|
rc = -EBUSY; |
|
goto fail_urdev_put; |
|
} |
|
device_destroy(vmur_class, urd->char_device->dev); |
|
cdev_del(urd->char_device); |
|
urd->char_device = NULL; |
|
rc = 0; |
|
|
|
fail_urdev_put: |
|
urdev_put(urd); |
|
return rc; |
|
} |
|
|
|
static int ur_set_offline(struct ccw_device *cdev) |
|
{ |
|
int rc; |
|
|
|
mutex_lock(&vmur_mutex); |
|
rc = ur_set_offline_force(cdev, 0); |
|
mutex_unlock(&vmur_mutex); |
|
return rc; |
|
} |
|
|
|
static void ur_remove(struct ccw_device *cdev) |
|
{ |
|
unsigned long flags; |
|
|
|
TRACE("ur_remove\n"); |
|
|
|
mutex_lock(&vmur_mutex); |
|
|
|
if (cdev->online) |
|
ur_set_offline_force(cdev, 1); |
|
ur_remove_attributes(&cdev->dev); |
|
|
|
spin_lock_irqsave(get_ccwdev_lock(cdev), flags); |
|
urdev_put(dev_get_drvdata(&cdev->dev)); |
|
dev_set_drvdata(&cdev->dev, NULL); |
|
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags); |
|
|
|
mutex_unlock(&vmur_mutex); |
|
} |
|
|
|
/* |
|
* Module initialisation and cleanup |
|
*/ |
|
static int __init ur_init(void) |
|
{ |
|
int rc; |
|
dev_t dev; |
|
|
|
if (!MACHINE_IS_VM) { |
|
pr_err("The %s cannot be loaded without z/VM\n", |
|
ur_banner); |
|
return -ENODEV; |
|
} |
|
|
|
vmur_dbf = debug_register("vmur", 4, 1, 4 * sizeof(long)); |
|
if (!vmur_dbf) |
|
return -ENOMEM; |
|
rc = debug_register_view(vmur_dbf, &debug_sprintf_view); |
|
if (rc) |
|
goto fail_free_dbf; |
|
|
|
debug_set_level(vmur_dbf, 6); |
|
|
|
vmur_class = class_create(THIS_MODULE, "vmur"); |
|
if (IS_ERR(vmur_class)) { |
|
rc = PTR_ERR(vmur_class); |
|
goto fail_free_dbf; |
|
} |
|
|
|
rc = ccw_driver_register(&ur_driver); |
|
if (rc) |
|
goto fail_class_destroy; |
|
|
|
rc = alloc_chrdev_region(&dev, 0, NUM_MINORS, "vmur"); |
|
if (rc) { |
|
pr_err("Kernel function alloc_chrdev_region failed with " |
|
"error code %d\n", rc); |
|
goto fail_unregister_driver; |
|
} |
|
ur_first_dev_maj_min = MKDEV(MAJOR(dev), 0); |
|
|
|
pr_info("%s loaded.\n", ur_banner); |
|
return 0; |
|
|
|
fail_unregister_driver: |
|
ccw_driver_unregister(&ur_driver); |
|
fail_class_destroy: |
|
class_destroy(vmur_class); |
|
fail_free_dbf: |
|
debug_unregister(vmur_dbf); |
|
return rc; |
|
} |
|
|
|
static void __exit ur_exit(void) |
|
{ |
|
unregister_chrdev_region(ur_first_dev_maj_min, NUM_MINORS); |
|
ccw_driver_unregister(&ur_driver); |
|
class_destroy(vmur_class); |
|
debug_unregister(vmur_dbf); |
|
pr_info("%s unloaded.\n", ur_banner); |
|
} |
|
|
|
module_init(ur_init); |
|
module_exit(ur_exit);
|
|
|