#include <asm/cio.h>
#include <asm/ccwdev.h>
#include <asm/debug.h>
+#include <asm/diag.h>
#include "vmur.h"
.set_offline = ur_set_offline,
};
+static DEFINE_MUTEX(vmur_mutex);
+
/*
* Allocation, freeing, getting and putting of urdev structures
+ *
+ * Each ur device (urd) contains a reference to its corresponding ccw device
+ * (cdev) using the urd->cdev pointer. Each ccw device has a reference to the
+ * ur device using the cdev->dev.driver_data pointer.
+ *
+ * urd references:
+ * - ur_probe gets a urd reference, ur_remove drops the reference
+ * (cdev->dev.driver_data)
+ * - ur_open gets a urd reference, ur_relase drops the reference
+ * (urf->urd)
+ *
+ * cdev references:
+ * - urdev_alloc get a cdev reference (urd->cdev)
+ * - urdev_free drops the cdev reference (urd->cdev)
+ *
+ * Setting and clearing of cdev->dev.driver_data is protected by the ccwdev lock
*/
static struct urdev *urdev_alloc(struct ccw_device *cdev)
{
urd = kzalloc(sizeof(struct urdev), GFP_KERNEL);
if (!urd)
return NULL;
- urd->cdev = cdev;
urd->reclen = cdev->id.driver_info;
ccw_device_get_id(cdev, &urd->dev_id);
mutex_init(&urd->io_mutex);
mutex_init(&urd->open_mutex);
+ atomic_set(&urd->ref_count, 1);
+ urd->cdev = cdev;
+ get_device(&cdev->dev);
return urd;
}
static void urdev_free(struct urdev *urd)
{
+ TRACE("urdev_free: %p\n", urd);
+ if (urd->cdev)
+ put_device(&urd->cdev->dev);
kfree(urd);
}
-/*
- * This is how the character device driver gets a reference to a
- * ur device. When this call returns successfully, a reference has
- * been taken (by get_device) on the underlying kobject. The recipient
- * of this urdev pointer must eventually drop it with urdev_put(urd)
- * which does the corresponding put_device().
- */
+static void urdev_get(struct urdev *urd)
+{
+ atomic_inc(&urd->ref_count);
+}
+
+static struct urdev *urdev_get_from_cdev(struct ccw_device *cdev)
+{
+ struct urdev *urd;
+ unsigned long flags;
+
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ urd = cdev->dev.driver_data;
+ if (urd)
+ urdev_get(urd);
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ return urd;
+}
+
static struct urdev *urdev_get_from_devno(u16 devno)
{
char bus_id[16];
struct ccw_device *cdev;
+ struct urdev *urd;
sprintf(bus_id, "0.0.%04x", devno);
cdev = get_ccwdev_by_busid(&ur_driver, bus_id);
if (!cdev)
return NULL;
-
- return cdev->dev.driver_data;
+ urd = urdev_get_from_cdev(cdev);
+ put_device(&cdev->dev);
+ return urd;
}
static void urdev_put(struct urdev *urd)
{
- put_device(&urd->cdev->dev);
+ if (atomic_dec_and_test(&urd->ref_count))
+ urdev_free(urd);
}
/*
* Low-level functions to do I/O to a ur device.
* alloc_chan_prog
+ * free_chan_prog
* do_ur_io
* ur_int_handler
*
* alloc_chan_prog allocates and builds the channel program
+ * free_chan_prog frees memory of the channel program
*
* do_ur_io issues the channel program to the device and blocks waiting
* on a completion event it publishes at urd->io_done. The function
* address pointer that alloc_chan_prog returned.
*/
+static void free_chan_prog(struct ccw1 *cpa)
+{
+ struct ccw1 *ptr = cpa;
+
+ while (ptr->cda) {
+ kfree((void *)(addr_t) ptr->cda);
+ ptr++;
+ }
+ kfree(cpa);
+}
/*
* alloc_chan_prog
* with a final NOP CCW command-chained on (which ensures that CE and DE
* are presented together in a single interrupt instead of as separate
* interrupts unless an incorrect length indication kicks in first). The
- * data length in each CCW is reclen. The caller must ensure that count
- * is an integral multiple of reclen.
- * The channel program pointer returned by this function must be freed
- * with kfree. The caller is responsible for checking that
- * count/reclen is not ridiculously large.
+ * data length in each CCW is reclen.
*/
-static struct ccw1 *alloc_chan_prog(char *buf, size_t count, size_t reclen)
+static struct ccw1 *alloc_chan_prog(const char __user *ubuf, int rec_count,
+ int reclen)
{
- size_t num_ccws;
struct ccw1 *cpa;
+ void *kbuf;
int i;
- TRACE("alloc_chan_prog(%p, %zu, %zu)\n", buf, count, reclen);
+ TRACE("alloc_chan_prog(%p, %i, %i)\n", ubuf, rec_count, reclen);
/*
* We chain a NOP onto the writes to force CE+DE together.
* That means we allocate room for CCWs to cover count/reclen
* records plus a NOP.
*/
- num_ccws = count / reclen + 1;
- cpa = kmalloc(num_ccws * sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
+ cpa = kzalloc((rec_count + 1) * sizeof(struct ccw1),
+ GFP_KERNEL | GFP_DMA);
if (!cpa)
- return NULL;
+ return ERR_PTR(-ENOMEM);
- for (i = 0; count; i++) {
+ for (i = 0; i < rec_count; i++) {
cpa[i].cmd_code = WRITE_CCW_CMD;
cpa[i].flags = CCW_FLAG_CC | CCW_FLAG_SLI;
cpa[i].count = reclen;
- cpa[i].cda = __pa(buf);
- buf += reclen;
- count -= reclen;
+ kbuf = kmalloc(reclen, GFP_KERNEL | GFP_DMA);
+ if (!kbuf) {
+ free_chan_prog(cpa);
+ return ERR_PTR(-ENOMEM);
+ }
+ cpa[i].cda = (u32)(addr_t) kbuf;
+ if (copy_from_user(kbuf, ubuf, reclen)) {
+ free_chan_prog(cpa);
+ return ERR_PTR(-EFAULT);
+ }
+ ubuf += reclen;
}
/* The following NOP CCW forces CE+DE to be presented together */
cpa[i].cmd_code = CCW_CMD_NOOP;
- cpa[i].flags = 0;
- cpa[i].count = 0;
- cpa[i].cda = 0;
-
return cpa;
}
{
int rc;
struct ccw_device *cdev = urd->cdev;
- DECLARE_COMPLETION(event);
+ DECLARE_COMPLETION_ONSTACK(event);
TRACE("do_ur_io: cpa=%p\n", cpa);
return;
}
urd = cdev->dev.driver_data;
+ BUG_ON(!urd);
/* On special conditions irb is an error pointer */
if (IS_ERR(irb))
urd->io_request_rc = PTR_ERR(irb);
static ssize_t ur_attr_reclen_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct urdev *urd = dev->driver_data;
+ struct urdev *urd;
+ int rc;
- return sprintf(buf, "%zu\n", urd->reclen);
+ urd = urdev_get_from_cdev(to_ccwdev(dev));
+ if (!urd)
+ return -ENODEV;
+ rc = sprintf(buf, "%zu\n", urd->reclen);
+ urdev_put(urd);
+ return rc;
}
static DEVICE_ATTR(reclen, 0444, ur_attr_reclen_show, NULL);
size_t count, size_t reclen, loff_t *ppos)
{
struct ccw1 *cpa;
- char *buf;
int rc;
- /* Data buffer must be under 2GB line for fmt1 CCWs: hence GFP_DMA */
- buf = kmalloc(count, GFP_KERNEL | GFP_DMA);
- if (!buf)
- return -ENOMEM;
-
- if (copy_from_user(buf, udata, count)) {
- rc = -EFAULT;
- goto fail_kfree_buf;
- }
-
- cpa = alloc_chan_prog(buf, count, reclen);
- if (!cpa) {
- rc = -ENOMEM;
- goto fail_kfree_buf;
- }
+ cpa = alloc_chan_prog(udata, count / reclen, reclen);
+ if (IS_ERR(cpa))
+ return PTR_ERR(cpa);
rc = do_ur_io(urd, cpa);
if (rc)
}
*ppos += count;
rc = count;
+
fail_kfree_cpa:
- kfree(cpa);
-fail_kfree_buf:
- kfree(buf);
+ free_chan_prog(cpa);
return rc;
}
return do_write(urf->urd, udata, count, urf->dev_reclen, ppos);
}
-static int do_diag_14(unsigned long rx, unsigned long ry1,
- unsigned long subcode)
-{
- register unsigned long _ry1 asm("2") = ry1;
- register unsigned long _ry2 asm("3") = subcode;
- int rc = 0;
-
- asm volatile(
-#ifdef CONFIG_64BIT
- " sam31\n"
- " diag %2,2,0x14\n"
- " sam64\n"
-#else
- " diag %2,2,0x14\n"
-#endif
- " ipm %0\n"
- " srl %0,28\n"
- : "=d" (rc), "+d" (_ry2)
- : "d" (rx), "d" (_ry1)
- : "cc");
-
- TRACE("diag 14: subcode=0x%lx, cc=%i\n", subcode, rc);
- return rc;
-}
-
/*
* diagnose code 0x14 subcode 0x0028 - position spool file to designated
* record
{
int cc;
- cc = do_diag_14(record, devno, 0x28);
+ cc = diag14(record, devno, 0x28);
switch (cc) {
case 0:
return 0;
{
int cc;
- cc = do_diag_14((unsigned long) buf, devno, 0x00);
+ cc = diag14((unsigned long) buf, devno, 0x00);
switch (cc) {
case 0:
return 0;
return rc;
len = min((size_t) PAGE_SIZE, count);
- buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ buf = (char *) __get_free_page(GFP_KERNEL | GFP_DMA);
if (!buf)
return -ENOMEM;
*offs += copied;
rc = copied;
fail:
- kfree(buf);
+ free_page((unsigned long) buf);
return rc;
}
{
int cc;
- cc = do_diag_14((unsigned long) buf, spid, 0xfff);
+ cc = diag14((unsigned long) buf, spid, 0xfff);
switch (cc) {
case 0:
return 0;
}
}
-static int verify_device(struct urdev *urd)
+static int verify_uri_device(struct urdev *urd)
{
- struct file_control_block fcb;
+ 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:
- /* check for empty reader device (beginning of chain) */
- rc = diag_read_next_file_info(&fcb, 0);
- if (rc)
- return rc;
-
- /* open file on virtual reader */
- buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- rc = diag_read_file(urd->dev_id.devno, buf);
- kfree(buf);
-
- if ((rc != 0) && (rc != -ENODATA)) /* EOF does not hurt */
- return rc;
- return 0;
+ return verify_uri_device(urd);
default:
return -ENOTSUPP;
}
}
-static int get_file_reclen(struct urdev *urd)
+static int get_uri_file_reclen(struct urdev *urd)
{
- struct file_control_block fcb;
+ 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:
- rc = diag_read_next_file_info(&fcb, 0);
- if (rc)
- return rc;
- break;
+ return get_uri_file_reclen(urd);
default:
return -ENOTSUPP;
}
- if (fcb.file_stat & FLG_CP_DUMP)
- return 0;
-
- return fcb.rec_len;
}
static int ur_open(struct inode *inode, struct file *file)
return newpos;
}
-static struct file_operations ur_fops = {
+static const struct file_operations ur_fops = {
.owner = THIS_MODULE,
.open = ur_open,
.release = ur_release,
/*
* ccw_device infrastructure:
- * ur_probe gets its own ref to the device (i.e. get_device),
- * creates the struct urdev, the device attributes, sets up
- * the interrupt handler and validates the virtual unit record device.
- * ur_remove removes the device attributes, frees the struct urdev
- * and drops (put_device) the ref to the device we got in ur_probe.
+ * 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 state=%d\n", cdev, *(int *) cdev->private);
-
- if (!get_device(&cdev->dev))
- return -ENODEV;
+ TRACE("ur_probe: cdev=%p\n", cdev);
+ mutex_lock(&vmur_mutex);
urd = urdev_alloc(cdev);
if (!urd) {
rc = -ENOMEM;
- goto fail;
+ goto fail_unlock;
}
+
rc = ur_create_attributes(&cdev->dev);
if (rc) {
rc = -ENOMEM;
- goto fail;
+ goto fail_urdev_put;
}
- cdev->dev.driver_data = urd;
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;
+ goto fail_remove_attr;
}
if ((urd->class != DEV_CLASS_UR_I) && (urd->class != DEV_CLASS_UR_O)) {
rc = -ENOTSUPP;
- goto fail;
+ goto fail_remove_attr;
}
+ spin_lock_irq(get_ccwdev_lock(cdev));
+ cdev->dev.driver_data = urd;
+ spin_unlock_irq(get_ccwdev_lock(cdev));
+ mutex_unlock(&vmur_mutex);
return 0;
-fail:
- urdev_free(urd);
- put_device(&cdev->dev);
- return rc;
-}
-
-static void ur_remove(struct ccw_device *cdev)
-{
- struct urdev *urd = cdev->dev.driver_data;
-
- TRACE("ur_remove\n");
- if (cdev->online)
- ur_set_offline(cdev);
+fail_remove_attr:
ur_remove_attributes(&cdev->dev);
- urdev_free(urd);
- put_device(&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)
int minor, major, rc;
char node_id[16];
- TRACE("ur_set_online: cdev=%p state=%d\n", cdev,
- *(int *) cdev->private);
+ TRACE("ur_set_online: cdev=%p\n", cdev);
- if (!try_module_get(ur_driver.owner))
- return -EINVAL;
+ 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;
+ }
- urd = (struct urdev *) cdev->dev.driver_data;
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_module_put;
+ goto fail_urdev_put;
}
cdev_init(urd->char_device, &ur_fops);
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);
-fail_module_put:
- module_put(ur_driver.owner);
-
+ urd->char_device = NULL;
+fail_urdev_put:
+ urdev_put(urd);
+fail_unlock:
+ mutex_unlock(&vmur_mutex);
return rc;
}
-static int ur_set_offline(struct ccw_device *cdev)
+static int ur_set_offline_force(struct ccw_device *cdev, int force)
{
struct urdev *urd;
+ int rc;
- TRACE("ur_set_offline: cdev=%p cdev->private=%p state=%d\n",
- cdev, cdev->private, *(int *) cdev->private);
- urd = (struct urdev *) cdev->dev.driver_data;
+ 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 && (atomic_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);
- module_put(ur_driver.owner);
+ urd->char_device = NULL;
+ rc = 0;
- return 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(cdev->dev.driver_data);
+ cdev->dev.driver_data = NULL;
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+
+ mutex_unlock(&vmur_mutex);
}
/*
projects / linux-2.6-omap-h63xx.git / blobdiff