/*
- * 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/blkdev.h>
#include <linux/poll.h>
#include <linux/cdev.h>
+#include <linux/jiffies.h>
#include <linux/percpu.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>
#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
#include <scsi/sg.h>
-static char bsg_version[] = "block layer sg (bsg) 0.4";
-
-struct bsg_command;
+#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
+#define BSG_VERSION "0.4"
struct bsg_device {
- struct gendisk *disk;
- 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;
- unsigned long *cmd_bitmap;
- struct bsg_command *cmd_map;
wait_queue_head_t wq_done;
wait_queue_head_t wq_free;
- char name[BDEVNAME_SIZE];
+ char name[20];
int max_queue;
unsigned long flags;
};
enum {
BSG_F_BLOCK = 1,
- BSG_F_WRITE_PERM = 2,
};
-/*
- * command allocation bitmap defines
- */
-#define BSG_CMDS_PAGE_ORDER (1)
-#define BSG_CMDS_PER_LONG (sizeof(unsigned long) * 8)
-#define BSG_CMDS_MASK (BSG_CMDS_PER_LONG - 1)
-#define BSG_CMDS_BYTES (PAGE_SIZE * (1 << BSG_CMDS_PAGE_ORDER))
-#define BSG_CMDS (BSG_CMDS_BYTES / sizeof(struct bsg_command))
+#define BSG_DEFAULT_CMDS 64
+#define BSG_MAX_DEVS 32768
#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
-#define list_entry_bc(entry) list_entry((entry), struct bsg_command, list)
-
-/*
- * just for testing
- */
-#define BSG_MAJOR (240)
-
static DEFINE_MUTEX(bsg_mutex);
-static int bsg_device_nr;
+static DEFINE_IDR(bsg_minor_idr);
-#define BSG_LIST_SIZE (8)
-#define bsg_list_idx(minor) ((minor) & (BSG_LIST_SIZE - 1))
-static struct hlist_head bsg_device_list[BSG_LIST_SIZE];
+#define BSG_LIST_ARRAY_SIZE 8
+static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE];
static struct class *bsg_class;
-static LIST_HEAD(bsg_class_list);
+static int bsg_major;
+
+static struct kmem_cache *bsg_cmd_cachep;
/*
* our internal command type
struct list_head list;
struct request *rq;
struct bio *bio;
+ struct bio *bidi_bio;
int err;
struct sg_io_v4 hdr;
- struct sg_io_v4 __user *uhdr;
char sense[SCSI_SENSE_BUFFERSIZE];
};
static void bsg_free_command(struct bsg_command *bc)
{
struct bsg_device *bd = bc->bd;
- unsigned long bitnr = bc - bd->cmd_map;
unsigned long flags;
- dprintk("%s: command bit offset %lu\n", bd->name, bitnr);
+ kmem_cache_free(bsg_cmd_cachep, bc);
spin_lock_irqsave(&bd->lock, flags);
bd->queued_cmds--;
- __clear_bit(bitnr, bd->cmd_bitmap);
spin_unlock_irqrestore(&bd->lock, flags);
wake_up(&bd->wq_free);
}
-static struct bsg_command *__bsg_alloc_command(struct bsg_device *bd)
+static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
{
- struct bsg_command *bc = NULL;
- unsigned long *map;
- int free_nr;
+ struct bsg_command *bc = ERR_PTR(-EINVAL);
spin_lock_irq(&bd->lock);
if (bd->queued_cmds >= bd->max_queue)
goto out;
- for (free_nr = 0, map = bd->cmd_bitmap; *map == ~0UL; map++)
- free_nr += BSG_CMDS_PER_LONG;
-
- BUG_ON(*map == ~0UL);
-
bd->queued_cmds++;
- free_nr += ffz(*map);
- __set_bit(free_nr, bd->cmd_bitmap);
spin_unlock_irq(&bd->lock);
- bc = bd->cmd_map + free_nr;
- memset(bc, 0, sizeof(*bc));
+ bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL);
+ if (unlikely(!bc)) {
+ spin_lock_irq(&bd->lock);
+ bd->queued_cmds--;
+ bc = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
bc->bd = bd;
INIT_LIST_HEAD(&bc->list);
- dprintk("%s: returning free cmd %p (bit %d)\n", bd->name, bc, free_nr);
+ dprintk("%s: returning free cmd %p\n", bd->name, bc);
return bc;
out:
- dprintk("%s: failed (depth %d)\n", bd->name, bd->queued_cmds);
spin_unlock_irq(&bd->lock);
return bc;
}
-static inline void
-bsg_del_done_cmd(struct bsg_device *bd, struct bsg_command *bc)
+static inline struct hlist_head *bsg_dev_idx_hash(int index)
{
- bd->done_cmds--;
- list_del(&bc->list);
+ return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)];
}
-static inline void
-bsg_add_done_cmd(struct bsg_device *bd, struct bsg_command *bc)
-{
- bd->done_cmds++;
- list_add_tail(&bc->list, &bd->done_list);
- wake_up(&bd->wq_done);
-}
-
-static inline int bsg_io_schedule(struct bsg_device *bd, int state)
+static int bsg_io_schedule(struct bsg_device *bd)
{
DEFINE_WAIT(wait);
int ret = 0;
goto unlock;
}
- prepare_to_wait(&bd->wq_done, &wait, state);
+ prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE);
spin_unlock_irq(&bd->lock);
io_schedule();
finish_wait(&bd->wq_done, &wait);
- if ((state == TASK_INTERRUPTIBLE) && signal_pending(current))
- ret = -ERESTARTSYS;
-
return ret;
unlock:
spin_unlock_irq(&bd->lock);
return ret;
}
-/*
- * get a new free command, blocking if needed and specified
- */
-static struct bsg_command *bsg_get_command(struct bsg_device *bd)
+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)
{
- struct bsg_command *bc;
- int ret;
-
- do {
- bc = __bsg_alloc_command(bd);
- if (bc)
- break;
-
- ret = bsg_io_schedule(bd, TASK_INTERRUPTIBLE);
- if (ret) {
- bc = ERR_PTR(ret);
- break;
- }
-
- } while (1);
-
- return bc;
-}
-
-static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq,
- struct sg_io_v4 *hdr, int 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))
return -EFAULT;
- if (blk_verify_command(rq->cmd, has_write_perm))
+
+ if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
+ if (blk_verify_command(rq->cmd, has_write_perm))
+ return -EPERM;
+ } else if (!capable(CAP_SYS_RAWIO))
return -EPERM;
/*
rq->cmd_len = hdr->request_len;
rq->cmd_type = REQ_TYPE_BLOCK_PC;
- rq->timeout = (hdr->timeout * HZ) / 1000;
+ rq->timeout = msecs_to_jiffies(hdr->timeout);
if (!rq->timeout)
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)
{
- 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;
+ int ret = 0;
- /* not supported currently */
- if (hdr->protocol || hdr->subprotocol)
+ if (hdr->guard != 'Q')
return -EINVAL;
- /*
- * looks sane, if no data then it should be fine from our POV
- */
- if (!hdr->dout_xfer_len && !hdr->din_xfer_len)
- return 0;
-
- /* not supported currently */
- if (hdr->dout_xfer_len && hdr->din_xfer_len)
- return -EINVAL;
+ switch (hdr->protocol) {
+ case BSG_PROTOCOL_SCSI:
+ switch (hdr->subprotocol) {
+ case BSG_SUB_PROTOCOL_SCSI_CMD:
+ case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ break;
+ default:
+ ret = -EINVAL;
+ }
*rw = hdr->dout_xfer_len ? WRITE : READ;
-
- return 0;
+ return ret;
}
/*
* 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 *rq;
- int ret, rw = 0; /* shut up gcc */
+ struct request_queue *q = bd->queue;
+ struct request *rq, *next_rq = NULL;
+ int ret, rw;
unsigned int dxfer_len;
void *dxferp = NULL;
* map scatter-gather elements seperately and string them to request
*/
rq = blk_get_request(q, rw, GFP_KERNEL);
- ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
- &bd->flags));
- if (ret) {
- blk_put_request(rq);
- return ERR_PTR(ret);
+ if (!rq)
+ return ERR_PTR(-ENOMEM);
+ ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
+ if (ret)
+ goto out;
+
+ if (rw == WRITE && hdr->din_xfer_len) {
+ if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ next_rq = blk_get_request(q, READ, GFP_KERNEL);
+ if (!next_rq) {
+ ret = -ENOMEM;
+ 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, NULL, dxferp,
+ hdr->din_xfer_len, GFP_KERNEL);
+ if (ret)
+ goto out;
}
if (hdr->dout_xfer_len) {
dxfer_len = 0;
if (dxfer_len) {
- ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
- if (ret) {
- dprintk("failed map at %d\n", ret);
- blk_put_request(rq);
- rq = ERR_PTR(ret);
- }
+ 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);
+ blk_put_request(next_rq);
+ }
+ return ERR_PTR(ret);
}
/*
struct bsg_device *bd = bc->bd;
unsigned long flags;
- dprintk("%s: finished rq %p bc %p, bio %p offset %Zd stat %d\n",
- bd->name, rq, bc, bc->bio, bc - bd->cmd_map, uptodate);
+ dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
+ bd->name, rq, bc, bc->bio, uptodate);
bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
spin_lock_irqsave(&bd->lock, flags);
- list_del(&bc->list);
- bsg_add_done_cmd(bd, bc);
+ list_move_tail(&bc->list, &bd->done_list);
+ bd->done_cmds++;
spin_unlock_irqrestore(&bd->lock, flags);
+
+ wake_up(&bd->wq_done);
}
/*
* 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
*/
bc->rq = rq;
bc->bio = rq->bio;
+ if (rq->next_rq)
+ bc->bidi_bio = rq->next_rq->bio;
bc->hdr.duration = jiffies;
spin_lock_irq(&bd->lock);
list_add_tail(&bc->list, &bd->busy_list);
dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
rq->end_io_data = bc;
- blk_execute_rq_nowait(q, bd->disk, rq, 1, bsg_rq_end_io);
+ blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
}
-static inline struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
+static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
{
struct bsg_command *bc = NULL;
spin_lock_irq(&bd->lock);
if (bd->done_cmds) {
- bc = list_entry_bc(bd->done_list.next);
- bsg_del_done_cmd(bd, bc);
+ bc = list_first_entry(&bd->done_list, struct bsg_command, list);
+ list_del(&bc->list);
+ bd->done_cmds--;
}
spin_unlock_irq(&bd->lock);
/*
* Get a finished command from the done list
*/
-static struct bsg_command *__bsg_get_done_cmd(struct bsg_device *bd, int state)
+static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
{
struct bsg_command *bc;
int ret;
if (bc)
break;
- ret = bsg_io_schedule(bd, state);
+ if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
+ bc = ERR_PTR(-EAGAIN);
+ break;
+ }
+
+ ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
if (ret) {
- bc = ERR_PTR(ret);
+ bc = ERR_PTR(-ERESTARTSYS);
break;
}
} while (1);
return bc;
}
-static struct bsg_command *
-bsg_get_done_cmd(struct bsg_device *bd, const struct iovec *iov)
-{
- return __bsg_get_done_cmd(bd, TASK_INTERRUPTIBLE);
-}
-
-static struct bsg_command *
-bsg_get_done_cmd_nosignals(struct bsg_device *bd)
-{
- return __bsg_get_done_cmd(bd, TASK_UNINTERRUPTIBLE);
-}
-
static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
- struct bio *bio)
+ struct bio *bio, struct bio *bidi_bio)
{
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) {
- int len = min((unsigned int) hdr->max_response_len,
- rq->sense_len);
+ int len = min_t(unsigned int, hdr->max_response_len,
+ rq->sense_len);
ret = copy_to_user((void*)(unsigned long)hdr->response,
rq->sense, len);
ret = -EFAULT;
}
+ 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
*/
ret = 0;
do {
- ret = bsg_io_schedule(bd, TASK_UNINTERRUPTIBLE);
+ ret = bsg_io_schedule(bd);
/*
* look for -ENODATA specifically -- we'll sometimes get
* -ERESTARTSYS when we've taken a signal, but we can't
*/
ret = 0;
do {
- bc = bsg_get_done_cmd_nosignals(bd);
-
- /*
- * we _must_ complete before restarting, because
- * bsg_release can't handle this failing.
- */
- if (PTR_ERR(bc) == -ERESTARTSYS)
- continue;
- if (IS_ERR(bc)) {
- ret = PTR_ERR(bc);
+ spin_lock_irq(&bd->lock);
+ if (!bd->queued_cmds) {
+ spin_unlock_irq(&bd->lock);
break;
}
+ spin_unlock_irq(&bd->lock);
- tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio);
+ bc = bsg_get_done_cmd(bd);
+ if (IS_ERR(bc))
+ break;
+
+ tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
+ bc->bidi_bio);
if (!ret)
ret = tret;
return ret;
}
-typedef struct bsg_command *(*bsg_command_callback)(struct bsg_device *bd, const struct iovec *iov);
-
-static ssize_t
-__bsg_read(char __user *buf, size_t count, bsg_command_callback get_bc,
- struct bsg_device *bd, const struct iovec *iov, ssize_t *bytes_read)
+static int
+__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
+ const struct iovec *iov, ssize_t *bytes_read)
{
struct bsg_command *bc;
int nr_commands, ret;
ret = 0;
nr_commands = count / sizeof(struct sg_io_v4);
while (nr_commands) {
- bc = get_bc(bd, iov);
+ bc = bsg_get_done_cmd(bd);
if (IS_ERR(bc)) {
ret = PTR_ERR(bc);
break;
* after completing the request. so do that here,
* bsg_complete_work() cannot do that for us
*/
- ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio);
+ ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
+ bc->bidi_bio);
- if (copy_to_user(buf, (char *) &bc->hdr, sizeof(bc->hdr)))
+ if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
ret = -EFAULT;
bsg_free_command(bc);
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.
+ */
static inline int err_block_err(int ret)
{
if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
dprintk("%s: read %Zd bytes\n", bd->name, count);
bsg_set_block(bd, file);
+
bytes_read = 0;
- ret = __bsg_read(buf, count, bsg_get_done_cmd,
- bd, NULL, &bytes_read);
+ ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
*ppos = bytes_read;
if (!bytes_read || (bytes_read && err_block_err(ret)))
return bytes_read;
}
-static ssize_t __bsg_write(struct bsg_device *bd, const char __user *buf,
- size_t count, ssize_t *bytes_read)
+static int __bsg_write(struct bsg_device *bd, const char __user *buf,
+ 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_get_command(bd);
- if (!bc)
- break;
+ bc = bsg_alloc_command(bd);
if (IS_ERR(bc)) {
ret = PTR_ERR(bc);
bc = NULL;
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;
rq = NULL;
nr_commands--;
buf += sizeof(struct sg_io_v4);
- *bytes_read += sizeof(struct sg_io_v4);
+ *bytes_written += sizeof(struct sg_io_v4);
}
if (bc)
bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
struct bsg_device *bd = file->private_data;
- ssize_t bytes_read;
+ ssize_t bytes_written;
int ret;
dprintk("%s: write %Zd bytes\n", bd->name, count);
bsg_set_block(bd, file);
- bsg_set_write_perm(bd, file);
- bytes_read = 0;
- ret = __bsg_write(bd, buf, count, &bytes_read);
- *ppos = bytes_read;
+ bytes_written = 0;
+ ret = __bsg_write(bd, buf, count, &bytes_written,
+ file->f_mode & FMODE_WRITE);
+
+ *ppos = bytes_written;
/*
* return bytes written on non-fatal errors
*/
- if (!bytes_read || (bytes_read && err_block_err(ret)))
- bytes_read = ret;
+ if (!bytes_written || (bytes_written && err_block_err(ret)))
+ bytes_written = ret;
- dprintk("%s: returning %Zd\n", bd->name, bytes_read);
- return bytes_read;
-}
-
-static void bsg_free_device(struct bsg_device *bd)
-{
- if (bd->cmd_map)
- free_pages((unsigned long) bd->cmd_map, BSG_CMDS_PAGE_ORDER);
-
- kfree(bd->cmd_bitmap);
- kfree(bd);
+ dprintk("%s: returning %Zd\n", bd->name, bytes_written);
+ return bytes_written;
}
static struct bsg_device *bsg_alloc_device(void)
{
- struct bsg_command *cmd_map;
- unsigned long *cmd_bitmap;
struct bsg_device *bd;
- int bits;
bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
if (unlikely(!bd))
spin_lock_init(&bd->lock);
- bd->max_queue = BSG_CMDS;
-
- bits = (BSG_CMDS / BSG_CMDS_PER_LONG) + 1;
- cmd_bitmap = kzalloc(bits * sizeof(unsigned long), GFP_KERNEL);
- if (!cmd_bitmap)
- goto out_free_bd;
- bd->cmd_bitmap = cmd_bitmap;
-
- cmd_map = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
- BSG_CMDS_PAGE_ORDER);
- if (!cmd_map)
- goto out_free_bitmap;
- bd->cmd_map = cmd_map;
+ bd->max_queue = BSG_DEFAULT_CMDS;
INIT_LIST_HEAD(&bd->busy_list);
INIT_LIST_HEAD(&bd->done_list);
init_waitqueue_head(&bd->wq_free);
init_waitqueue_head(&bd->wq_done);
return bd;
+}
-out_free_bitmap:
- kfree(cmd_bitmap);
-out_free_bd:
- kfree(bd);
- return NULL;
+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);
- bsg_free_device(bd);
+ 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;
}
static struct bsg_device *bsg_add_device(struct inode *inode,
- struct gendisk *disk,
+ struct request_queue *rq,
struct file *file)
{
- struct bsg_device *bd = NULL;
+ 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;
- bd->disk = disk;
- bd->queue = disk->queue;
- kobject_get(&disk->queue->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_device_list[bsg_list_idx(bd->minor)]);
+ hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
- strncpy(bd->name, disk->disk_name, 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 hlist_head *list = &bsg_device_list[bsg_list_idx(minor)];
- struct bsg_device *bd = NULL;
+ struct bsg_device *bd;
struct hlist_node *entry;
mutex_lock(&bsg_mutex);
- hlist_for_each(entry, list) {
- 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;
}
static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
{
- struct bsg_device *bd = __bsg_get_device(iminor(inode));
- struct bsg_class_device *bcd, *__bcd;
-
- if (bd)
- return bd;
+ struct bsg_device *bd;
+ struct bsg_class_device *bcd;
/*
* find the class device
*/
- bcd = NULL;
mutex_lock(&bsg_mutex);
- list_for_each_entry(__bcd, &bsg_class_list, list) {
- if (__bcd->minor == iminor(inode)) {
- bcd = __bcd;
- break;
- }
- }
+ 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->disk, 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);
return mask;
}
-static int
-bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
- unsigned long arg)
+static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct bsg_device *bd = file->private_data;
int __user *uarg = (int __user *) arg;
-
- if (!bd)
- return -ENXIO;
+ int ret;
switch (cmd) {
/*
*/
case SG_GET_COMMAND_Q:
return put_user(bd->max_queue, uarg);
- case SG_SET_COMMAND_Q: {
+ case SG_SET_COMMAND_Q: {
int queue;
if (get_user(queue, uarg))
return -EFAULT;
- if (queue > BSG_CMDS || queue < 1)
+ if (queue < 1)
return -EINVAL;
+ spin_lock_irq(&bd->lock);
bd->max_queue = queue;
+ spin_unlock_irq(&bd->lock);
return 0;
}
case SG_EMULATED_HOST:
case SCSI_IOCTL_SEND_COMMAND: {
void __user *uarg = (void __user *) arg;
- return scsi_cmd_ioctl(file, bd->disk, cmd, uarg);
+ return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
}
case SG_IO: {
struct request *rq;
- struct bio *bio;
+ 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;
- blk_execute_rq(bd->queue, bd->disk, rq, 0);
- blk_complete_sgv4_hdr_rq(rq, &hdr, bio);
+ if (rq->next_rq)
+ bidi_bio = rq->next_rq->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,
.open = bsg_open,
.release = bsg_release,
- .ioctl = bsg_ioctl,
+ .unlocked_ioctl = bsg_ioctl,
.owner = THIS_MODULE,
};
-void bsg_unregister_disk(struct gendisk *disk)
+void bsg_unregister_queue(struct request_queue *q)
{
- struct bsg_class_device *bcd = &disk->bsg_dev;
+ struct bsg_class_device *bcd = &q->bsg_dev;
if (!bcd->class_dev)
return;
mutex_lock(&bsg_mutex);
- sysfs_remove_link(&bcd->disk->queue->kobj, "bsg");
- class_device_destroy(bsg_class, MKDEV(BSG_MAJOR, bcd->minor));
+ idr_remove(&bsg_minor_idr, bcd->minor);
+ sysfs_remove_link(&q->kobj, "bsg");
+ device_unregister(bcd->class_dev);
bcd->class_dev = NULL;
- list_del_init(&bcd->list);
+ kref_put(&bcd->ref, bsg_kref_release_function);
mutex_unlock(&bsg_mutex);
}
+EXPORT_SYMBOL_GPL(bsg_unregister_queue);
-int bsg_register_disk(struct gendisk *disk)
+int bsg_register_queue(struct request_queue *q, struct device *parent,
+ const char *name, void (*release)(struct device *))
{
- request_queue_t *q = disk->queue;
struct bsg_class_device *bcd;
dev_t dev;
+ int ret, minor;
+ struct device *class_dev = NULL;
+ const char *devname;
+
+ if (name)
+ devname = name;
+ else
+ devname = dev_name(parent);
/*
* we need a proper transport to send commands, not a stacked device
if (!q->request_fn)
return 0;
- bcd = &disk->bsg_dev;
+ bcd = &q->bsg_dev;
memset(bcd, 0, sizeof(*bcd));
- INIT_LIST_HEAD(&bcd->list);
mutex_lock(&bsg_mutex);
- dev = MKDEV(BSG_MAJOR, bsg_device_nr);
- bcd->minor = bsg_device_nr;
- bsg_device_nr++;
- bcd->disk = disk;
- bcd->class_dev = class_device_create(bsg_class, NULL, dev, bcd->dev, "%s", disk->disk_name);
- list_add_tail(&bcd->list, &bsg_class_list);
- sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
+
+ ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
+ if (!ret) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
+ if (ret < 0)
+ goto unlock;
+
+ if (minor >= BSG_MAX_DEVS) {
+ printk(KERN_ERR "bsg: too many bsg devices\n");
+ ret = -EINVAL;
+ goto remove_idr;
+ }
+
+ bcd->minor = minor;
+ bcd->queue = q;
+ bcd->parent = get_device(parent);
+ bcd->release = release;
+ kref_init(&bcd->ref);
+ dev = MKDEV(bsg_major, bcd->minor);
+ class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
+ if (IS_ERR(class_dev)) {
+ ret = PTR_ERR(class_dev);
+ goto put_dev;
+ }
+ bcd->class_dev = class_dev;
+
+ if (q->kobj.sd) {
+ ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
+ if (ret)
+ goto unregister_class_dev;
+ }
+
mutex_unlock(&bsg_mutex);
return 0;
+
+unregister_class_dev:
+ device_unregister(class_dev);
+put_dev:
+ put_device(parent);
+remove_idr:
+ idr_remove(&bsg_minor_idr, minor);
+unlock:
+ mutex_unlock(&bsg_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bsg_register_queue);
+
+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)
{
int ret, i;
+ dev_t devid;
- for (i = 0; i < BSG_LIST_SIZE; i++)
+ bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
+ sizeof(struct bsg_command), 0, 0, NULL);
+ if (!bsg_cmd_cachep) {
+ printk(KERN_ERR "bsg: failed creating slab cache\n");
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
INIT_HLIST_HEAD(&bsg_device_list[i]);
bsg_class = class_create(THIS_MODULE, "bsg");
- if (IS_ERR(bsg_class))
- return PTR_ERR(bsg_class);
-
- ret = register_chrdev(BSG_MAJOR, "bsg", &bsg_fops);
- if (ret) {
- class_destroy(bsg_class);
- return ret;
+ if (IS_ERR(bsg_class)) {
+ ret = PTR_ERR(bsg_class);
+ goto destroy_kmemcache;
}
+ bsg_class->devnode = bsg_devnode;
- printk(KERN_INFO "%s loaded\n", bsg_version);
+ ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
+ if (ret)
+ goto destroy_bsg_class;
+
+ bsg_major = MAJOR(devid);
+
+ cdev_init(&bsg_cdev, &bsg_fops);
+ ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
+ if (ret)
+ goto unregister_chrdev;
+
+ printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
+ " loaded (major %d)\n", bsg_major);
return 0;
+unregister_chrdev:
+ unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
+destroy_bsg_class:
+ class_destroy(bsg_class);
+destroy_kmemcache:
+ kmem_cache_destroy(bsg_cmd_cachep);
+ return ret;
}
MODULE_AUTHOR("Jens Axboe");
-MODULE_DESCRIPTION("Block layer SGSI generic (sg) driver");
+MODULE_DESCRIPTION(BSG_DESCRIPTION);
MODULE_LICENSE("GPL");
-subsys_initcall(bsg_init);
+device_initcall(bsg_init);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff