/*
- * bsg.c - block layer implementation of the sg v3 interface
+ * bsg.c - block layer implementation of the sg v4 interface
*
* Copyright (C) 2004 Jens Axboe <axboe@suse.de> SUSE Labs
* Copyright (C) 2004 Peter M. Jones <pjones@redhat.com>
* archive for more details.
*
*/
-/*
- * TODO
- * - Should this get merged, block/scsi_ioctl.c will be migrated into
- * this file. To keep maintenance down, it's easier to have them
- * seperated right now.
- *
- */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/uio.h>
#include <linux/idr.h>
#include <linux/bsg.h>
+#include <linux/smp_lock.h>
#include <scsi/scsi.h>
#include <scsi/scsi_ioctl.h>
#define BSG_VERSION "0.4"
struct bsg_device {
- request_queue_t *queue;
+ struct request_queue *queue;
spinlock_t lock;
struct list_head busy_list;
struct list_head done_list;
struct hlist_node dev_list;
atomic_t ref_count;
- int minor;
int queued_cmds;
int done_cmds;
wait_queue_head_t wq_done;
wait_queue_head_t wq_free;
- char name[BUS_ID_SIZE];
+ char name[20];
int max_queue;
unsigned long flags;
};
enum {
BSG_F_BLOCK = 1,
- BSG_F_WRITE_PERM = 2,
};
#define BSG_DEFAULT_CMDS 64
#undef BSG_DEBUG
#ifdef BSG_DEBUG
-#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ##args)
+#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ##args)
#else
#define dprintk(fmt, args...)
#endif
struct bio *bidi_bio;
int err;
struct sg_io_v4 hdr;
- struct sg_io_v4 __user *uhdr;
char sense[SCSI_SENSE_BUFFERSIZE];
};
return ret;
}
-static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq,
- struct sg_io_v4 *hdr, int has_write_perm)
+static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
+ struct sg_io_v4 *hdr, struct bsg_device *bd,
+ fmode_t has_write_perm)
{
- memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
+ if (hdr->request_len > BLK_MAX_CDB) {
+ rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
+ if (!rq->cmd)
+ return -ENOMEM;
+ }
if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
hdr->request_len))
rq->timeout = q->sg_timeout;
if (!rq->timeout)
rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
+ if (rq->timeout < BLK_MIN_SG_TIMEOUT)
+ rq->timeout = BLK_MIN_SG_TIMEOUT;
return 0;
}
* Check if sg_io_v4 from user is allowed and valid
*/
static int
-bsg_validate_sgv4_hdr(request_queue_t *q, struct sg_io_v4 *hdr, int *rw)
+bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
{
int ret = 0;
if (hdr->guard != 'Q')
return -EINVAL;
- if (hdr->request_len > BLK_MAX_CDB)
- return -EINVAL;
- if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
- hdr->din_xfer_len > (q->max_sectors << 9))
- return -EIO;
switch (hdr->protocol) {
case BSG_PROTOCOL_SCSI:
* map sg_io_v4 to a request.
*/
static struct request *
-bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
+bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
+ u8 *sense)
{
- request_queue_t *q = bd->queue;
+ struct request_queue *q = bd->queue;
struct request *rq, *next_rq = NULL;
int ret, rw;
unsigned int dxfer_len;
rq = blk_get_request(q, rw, GFP_KERNEL);
if (!rq)
return ERR_PTR(-ENOMEM);
- ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
- &bd->flags));
+ ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
if (ret)
goto out;
goto out;
}
rq->next_rq = next_rq;
+ next_rq->cmd_type = rq->cmd_type;
dxferp = (void*)(unsigned long)hdr->din_xferp;
- ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len);
+ ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
+ hdr->din_xfer_len, GFP_KERNEL);
if (ret)
goto out;
}
dxfer_len = 0;
if (dxfer_len) {
- ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
+ ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
+ GFP_KERNEL);
if (ret)
goto out;
}
+
+ rq->sense = sense;
+ rq->sense_len = 0;
+
return rq;
out:
+ if (rq->cmd != rq->__cmd)
+ kfree(rq->cmd);
blk_put_request(rq);
if (next_rq) {
blk_rq_unmap_user(next_rq->bio);
* do final setup of a 'bc' and submit the matching 'rq' to the block
* layer for io
*/
-static void bsg_add_command(struct bsg_device *bd, request_queue_t *q,
+static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
struct bsg_command *bc, struct request *rq)
{
- rq->sense = bc->sense;
- rq->sense_len = 0;
+ int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
/*
* add bc command to busy queue and submit rq for io
dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
rq->end_io_data = bc;
- blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
+ blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
}
static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
spin_lock_irq(&bd->lock);
if (bd->done_cmds) {
- bc = list_entry(bd->done_list.next, struct bsg_command, list);
+ bc = list_first_entry(&bd->done_list, struct bsg_command, list);
list_del(&bc->list);
bd->done_cmds--;
}
{
int ret = 0;
- dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
+ dprintk("rq %p bio %p 0x%x\n", rq, bio, rq->errors);
/*
* fill in all the output members
*/
hdr->info = 0;
if (hdr->device_status || hdr->transport_status || hdr->driver_status)
hdr->info |= SG_INFO_CHECK;
- hdr->din_resid = rq->data_len;
hdr->response_len = 0;
if (rq->sense_len && hdr->response) {
}
if (rq->next_rq) {
+ hdr->dout_resid = rq->resid_len;
+ hdr->din_resid = rq->next_rq->resid_len;
blk_rq_unmap_user(bidi_bio);
blk_put_request(rq->next_rq);
- }
+ } else if (rq_data_dir(rq) == READ)
+ hdr->din_resid = rq->resid_len;
+ else
+ hdr->dout_resid = rq->resid_len;
+
+ /*
+ * If the request generated a negative error number, return it
+ * (providing we aren't already returning an error); if it's
+ * just a protocol response (i.e. non negative), that gets
+ * processed above.
+ */
+ if (!ret && rq->errors < 0)
+ ret = rq->errors;
blk_rq_unmap_user(bio);
+ if (rq->cmd != rq->__cmd)
+ kfree(rq->cmd);
blk_put_request(rq);
return ret;
dprintk("%s: entered\n", bd->name);
- set_bit(BSG_F_BLOCK, &bd->flags);
-
/*
* wait for all commands to complete
*/
set_bit(BSG_F_BLOCK, &bd->flags);
}
-static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
-{
- if (file->f_mode & FMODE_WRITE)
- set_bit(BSG_F_WRITE_PERM, &bd->flags);
- else
- clear_bit(BSG_F_WRITE_PERM, &bd->flags);
-}
-
/*
* Check if the error is a "real" error that we should return.
*/
dprintk("%s: read %Zd bytes\n", bd->name, count);
bsg_set_block(bd, file);
+
bytes_read = 0;
ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
*ppos = bytes_read;
}
static int __bsg_write(struct bsg_device *bd, const char __user *buf,
- size_t count, ssize_t *bytes_written)
+ size_t count, ssize_t *bytes_written,
+ fmode_t has_write_perm)
{
struct bsg_command *bc;
struct request *rq;
bc = NULL;
ret = 0;
while (nr_commands) {
- request_queue_t *q = bd->queue;
+ struct request_queue *q = bd->queue;
bc = bsg_alloc_command(bd);
if (IS_ERR(bc)) {
break;
}
- bc->uhdr = (struct sg_io_v4 __user *) buf;
if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
ret = -EFAULT;
break;
/*
* get a request, fill in the blanks, and add to request queue
*/
- rq = bsg_map_hdr(bd, &bc->hdr);
+ rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense);
if (IS_ERR(rq)) {
ret = PTR_ERR(rq);
rq = NULL;
dprintk("%s: write %Zd bytes\n", bd->name, count);
bsg_set_block(bd, file);
- bsg_set_write_perm(bd, file);
bytes_written = 0;
- ret = __bsg_write(bd, buf, count, &bytes_written);
+ ret = __bsg_write(bd, buf, count, &bytes_written,
+ file->f_mode & FMODE_WRITE);
+
*ppos = bytes_written;
/*
return bd;
}
+static void bsg_kref_release_function(struct kref *kref)
+{
+ struct bsg_class_device *bcd =
+ container_of(kref, struct bsg_class_device, ref);
+ struct device *parent = bcd->parent;
+
+ if (bcd->release)
+ bcd->release(bcd->parent);
+
+ put_device(parent);
+}
+
static int bsg_put_device(struct bsg_device *bd)
{
- int ret = 0;
+ int ret = 0, do_free;
+ struct request_queue *q = bd->queue;
mutex_lock(&bsg_mutex);
- if (!atomic_dec_and_test(&bd->ref_count))
+ do_free = atomic_dec_and_test(&bd->ref_count);
+ if (!do_free) {
+ mutex_unlock(&bsg_mutex);
goto out;
+ }
+
+ hlist_del(&bd->dev_list);
+ mutex_unlock(&bsg_mutex);
dprintk("%s: tearing down\n", bd->name);
*/
ret = bsg_complete_all_commands(bd);
- blk_put_queue(bd->queue);
- hlist_del(&bd->dev_list);
kfree(bd);
out:
- mutex_unlock(&bsg_mutex);
+ kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
+ if (do_free)
+ blk_put_queue(q);
return ret;
}
struct file *file)
{
struct bsg_device *bd;
+ int ret;
#ifdef BSG_DEBUG
unsigned char buf[32];
#endif
+ ret = blk_get_queue(rq);
+ if (ret)
+ return ERR_PTR(-ENXIO);
bd = bsg_alloc_device();
- if (!bd)
+ if (!bd) {
+ blk_put_queue(rq);
return ERR_PTR(-ENOMEM);
+ }
bd->queue = rq;
- kobject_get(&rq->kobj);
+
bsg_set_block(bd, file);
atomic_set(&bd->ref_count, 1);
- bd->minor = iminor(inode);
mutex_lock(&bsg_mutex);
- hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(bd->minor));
+ hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
- strncpy(bd->name, rq->bsg_dev.class_dev->class_id, sizeof(bd->name) - 1);
+ strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
dprintk("bound to <%s>, max queue %d\n",
format_dev_t(buf, inode->i_rdev), bd->max_queue);
return bd;
}
-static struct bsg_device *__bsg_get_device(int minor)
+static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
{
- struct bsg_device *bd = NULL;
+ struct bsg_device *bd;
struct hlist_node *entry;
mutex_lock(&bsg_mutex);
- hlist_for_each(entry, bsg_dev_idx_hash(minor)) {
- bd = hlist_entry(entry, struct bsg_device, dev_list);
- if (bd->minor == minor) {
+ hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
+ if (bd->queue == q) {
atomic_inc(&bd->ref_count);
- break;
+ goto found;
}
-
- bd = NULL;
}
-
+ bd = NULL;
+found:
mutex_unlock(&bsg_mutex);
return bd;
}
struct bsg_device *bd;
struct bsg_class_device *bcd;
- bd = __bsg_get_device(iminor(inode));
- if (bd)
- return bd;
-
/*
* find the class device
*/
mutex_lock(&bsg_mutex);
bcd = idr_find(&bsg_minor_idr, iminor(inode));
+ if (bcd)
+ kref_get(&bcd->ref);
mutex_unlock(&bsg_mutex);
if (!bcd)
return ERR_PTR(-ENODEV);
- return bsg_add_device(inode, bcd->queue, file);
+ bd = __bsg_get_device(iminor(inode), bcd->queue);
+ if (bd)
+ return bd;
+
+ bd = bsg_add_device(inode, bcd->queue, file);
+ if (IS_ERR(bd))
+ kref_put(&bcd->ref, bsg_kref_release_function);
+
+ return bd;
}
static int bsg_open(struct inode *inode, struct file *file)
{
- struct bsg_device *bd = bsg_get_device(inode, file);
+ struct bsg_device *bd;
+
+ lock_kernel();
+ bd = bsg_get_device(inode, file);
+ unlock_kernel();
if (IS_ERR(bd))
return PTR_ERR(bd);
{
struct bsg_device *bd = file->private_data;
int __user *uarg = (int __user *) arg;
+ int ret;
switch (cmd) {
/*
case SG_EMULATED_HOST:
case SCSI_IOCTL_SEND_COMMAND: {
void __user *uarg = (void __user *) arg;
- return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
+ return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
}
case SG_IO: {
struct request *rq;
struct bio *bio, *bidi_bio = NULL;
struct sg_io_v4 hdr;
+ int at_head;
+ u8 sense[SCSI_SENSE_BUFFERSIZE];
if (copy_from_user(&hdr, uarg, sizeof(hdr)))
return -EFAULT;
- rq = bsg_map_hdr(bd, &hdr);
+ rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
if (IS_ERR(rq))
return PTR_ERR(rq);
bio = rq->bio;
if (rq->next_rq)
bidi_bio = rq->next_rq->bio;
- blk_execute_rq(bd->queue, NULL, rq, 0);
- blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
+
+ at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
+ blk_execute_rq(bd->queue, NULL, rq, at_head);
+ ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
if (copy_to_user(uarg, &hdr, sizeof(hdr)))
return -EFAULT;
- return 0;
+ return ret;
}
/*
* block device ioctls
}
}
-static struct file_operations bsg_fops = {
+static const struct file_operations bsg_fops = {
.read = bsg_read,
.write = bsg_write,
.poll = bsg_poll,
mutex_lock(&bsg_mutex);
idr_remove(&bsg_minor_idr, bcd->minor);
sysfs_remove_link(&q->kobj, "bsg");
- class_device_unregister(bcd->class_dev);
- put_device(bcd->dev);
+ device_unregister(bcd->class_dev);
bcd->class_dev = NULL;
- bcd->dev = NULL;
+ kref_put(&bcd->ref, bsg_kref_release_function);
mutex_unlock(&bsg_mutex);
}
EXPORT_SYMBOL_GPL(bsg_unregister_queue);
-int bsg_register_queue(struct request_queue *q, struct device *gdev,
- const char *name)
+int bsg_register_queue(struct request_queue *q, struct device *parent,
+ const char *name, void (*release)(struct device *))
{
struct bsg_class_device *bcd;
dev_t dev;
int ret, minor;
- struct class_device *class_dev = NULL;
+ struct device *class_dev = NULL;
const char *devname;
if (name)
devname = name;
else
- devname = gdev->bus_id;
+ devname = dev_name(parent);
/*
* we need a proper transport to send commands, not a stacked device
bcd->minor = minor;
bcd->queue = q;
- bcd->dev = get_device(gdev);
+ bcd->parent = get_device(parent);
+ bcd->release = release;
+ kref_init(&bcd->ref);
dev = MKDEV(bsg_major, bcd->minor);
- class_dev = class_device_create(bsg_class, NULL, dev, gdev, "%s",
- devname);
+ class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
if (IS_ERR(class_dev)) {
ret = PTR_ERR(class_dev);
goto put_dev;
return 0;
unregister_class_dev:
- class_device_unregister(class_dev);
+ device_unregister(class_dev);
put_dev:
- put_device(gdev);
+ put_device(parent);
remove_idr:
idr_remove(&bsg_minor_idr, minor);
unlock:
}
EXPORT_SYMBOL_GPL(bsg_register_queue);
-static struct cdev bsg_cdev = {
- .kobj = {.name = "bsg", },
- .owner = THIS_MODULE,
-};
+static struct cdev bsg_cdev;
+
+static char *bsg_devnode(struct device *dev, mode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "bsg/%s", dev_name(dev));
+}
static int __init bsg_init(void)
{
ret = PTR_ERR(bsg_class);
goto destroy_kmemcache;
}
+ bsg_class->devnode = bsg_devnode;
ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
if (ret)