X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=block%2Fbsg.c;h=82d58829ba591eeef13a3ed4eca96b8a019c4d85;hb=c3935e30495869dd611e1cd62253c94ebc7c6c04;hp=4ef3cc550244dfa4068cdfd49aa39a6e4c3e9183;hpb=292b7f27129272c9ec0ee5fa56abb6f9061b1d83;p=safe%2Fjmp%2Flinux-2.6 diff --git a/block/bsg.c b/block/bsg.c index 4ef3cc5..82d5882 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -1,5 +1,5 @@ /* - * 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 SUSE Labs * Copyright (C) 2004 Peter M. Jones @@ -9,22 +9,19 @@ * 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 #include #include #include #include #include +#include #include #include +#include #include +#include +#include #include #include @@ -33,28 +30,27 @@ #include #include -static char bsg_version[] = "block layer sg (bsg) 0.4"; +#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver" +#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 @@ -63,27 +59,19 @@ enum { #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, bsg_minor_idx; +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; @@ -95,9 +83,9 @@ struct bsg_command { 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]; }; @@ -115,9 +103,9 @@ static void bsg_free_command(struct bsg_command *bc) 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; + struct bsg_command *bc = ERR_PTR(-EINVAL); spin_lock_irq(&bd->lock); @@ -127,14 +115,14 @@ static struct bsg_command *__bsg_alloc_command(struct bsg_device *bd) bd->queued_cmds++; spin_unlock_irq(&bd->lock); - bc = kmem_cache_alloc(bsg_cmd_cachep, GFP_USER); + 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; } - memset(bc, 0, sizeof(*bc)); bc->bd = bd; INIT_LIST_HEAD(&bc->list); dprintk("%s: returning free cmd %p\n", bd->name, bc); @@ -144,22 +132,12 @@ out: return bc; } -static inline void -bsg_del_done_cmd(struct bsg_device *bd, struct bsg_command *bc) -{ - bd->done_cmds--; - list_del(&bc->list); -} - -static inline void -bsg_add_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_add_tail(&bc->list, &bd->done_list); - wake_up(&bd->wq_done); + return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)]; } -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; @@ -184,53 +162,35 @@ static inline int bsg_io_schedule(struct bsg_device *bd, int state) 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; /* @@ -239,11 +199,13 @@ static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq, 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; } @@ -252,44 +214,41 @@ static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq, * 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; @@ -302,14 +261,34 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) return ERR_PTR(ret); /* - * map scatter-gather elements seperately and string them to request + * map scatter-gather elements separately 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) { @@ -322,15 +301,25 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) 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); } /* @@ -349,26 +338,29 @@ static void bsg_rq_end_io(struct request *rq, int 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); @@ -377,17 +369,18 @@ static void bsg_add_command(struct bsg_device *bd, request_queue_t *q, 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 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); @@ -397,7 +390,7 @@ static inline struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd) /* * 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; @@ -407,9 +400,14 @@ static struct bsg_command *__bsg_get_done_cmd(struct bsg_device *bd, int state) 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); @@ -419,24 +417,12 @@ static struct bsg_command *__bsg_get_done_cmd(struct bsg_device *bd, int state) 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 */ @@ -446,12 +432,11 @@ static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, 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); @@ -461,7 +446,28 @@ static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, 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; @@ -474,14 +480,12 @@ static int bsg_complete_all_commands(struct bsg_device *bd) 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 @@ -496,20 +500,19 @@ static int bsg_complete_all_commands(struct bsg_device *bd) */ 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); + + bc = bsg_get_done_cmd(bd); + if (IS_ERR(bc)) + break; - tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio); + tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio, + bc->bidi_bio); if (!ret) ret = tret; @@ -519,11 +522,9 @@ static int bsg_complete_all_commands(struct bsg_device *bd) 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; @@ -534,7 +535,7 @@ __bsg_read(char __user *buf, size_t count, bsg_command_callback get_bc, 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; @@ -545,9 +546,10 @@ __bsg_read(char __user *buf, size_t count, bsg_command_callback get_bc, * 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); @@ -571,14 +573,9 @@ static inline void bsg_set_block(struct bsg_device *bd, struct file *file) 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) @@ -597,9 +594,9 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) 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))) @@ -608,8 +605,9 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) 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; @@ -623,18 +621,15 @@ static ssize_t __bsg_write(struct bsg_device *bd, const char __user *buf, 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; @@ -643,7 +638,7 @@ static ssize_t __bsg_write(struct bsg_device *bd, const char __user *buf, /* * 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; @@ -655,7 +650,7 @@ static ssize_t __bsg_write(struct bsg_device *bd, const char __user *buf, 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) @@ -668,26 +663,27 @@ static ssize_t 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; + dprintk("%s: returning %Zd\n", bd->name, bytes_written); + return bytes_written; } static struct bsg_device *bsg_alloc_device(void) @@ -711,14 +707,33 @@ static struct bsg_device *bsg_alloc_device(void) 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); @@ -734,11 +749,11 @@ static int bsg_put_device(struct bsg_device *bd) */ 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; } @@ -746,25 +761,30 @@ static struct bsg_device *bsg_add_device(struct inode *inode, 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; - 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_device_list[bsg_list_idx(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); @@ -772,58 +792,60 @@ static struct bsg_device *bsg_add_device(struct inode *inode, 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->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); @@ -858,15 +880,11 @@ static unsigned int bsg_poll(struct file *file, poll_table *wait) 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) { /* @@ -901,28 +919,34 @@ bsg_ioctl(struct inode *inode, struct file *file, unsigned int 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; + 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, NULL, 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 @@ -936,13 +960,13 @@ bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd, } } -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, }; @@ -954,20 +978,28 @@ void bsg_unregister_queue(struct request_queue *q) return; mutex_lock(&bsg_mutex); + idr_remove(&bsg_minor_idr, bcd->minor); sysfs_remove_link(&q->kobj, "bsg"); - class_device_destroy(bsg_class, MKDEV(BSG_MAJOR, bcd->minor)); + device_unregister(bcd->class_dev); bcd->class_dev = NULL; - list_del_init(&bcd->list); - bsg_device_nr--; + 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, 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, *__bcd; + struct bsg_class_device *bcd; dev_t dev; - int ret = -EMFILE; - struct class_device *class_dev = NULL; + 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 @@ -977,134 +1009,113 @@ int bsg_register_queue(struct request_queue *q, char *name) bcd = &q->bsg_dev; memset(bcd, 0, sizeof(*bcd)); - INIT_LIST_HEAD(&bcd->list); mutex_lock(&bsg_mutex); - if (bsg_device_nr == BSG_MAX_DEVS) { - printk(KERN_ERR "bsg: too many bsg devices\n"); - goto err; - } -retry: - list_for_each_entry(__bcd, &bsg_class_list, list) { - if (__bcd->minor == bsg_minor_idx) { - bsg_minor_idx++; - if (bsg_minor_idx == BSG_MAX_DEVS) - bsg_minor_idx = 0; - goto retry; - } + ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL); + if (!ret) { + ret = -ENOMEM; + goto unlock; } - bcd->minor = bsg_minor_idx++; - if (bsg_minor_idx == BSG_MAX_DEVS) - bsg_minor_idx = 0; + 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; - dev = MKDEV(BSG_MAJOR, bcd->minor); - class_dev = class_device_create(bsg_class, NULL, dev, bcd->dev, "%s", name); + 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 err; + goto put_dev; } bcd->class_dev = class_dev; - if (q->kobj.dentry) { + if (q->kobj.sd) { ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg"); if (ret) - goto err; + goto unregister_class_dev; } - list_add_tail(&bcd->list, &bsg_class_list); - bsg_device_nr++; - mutex_unlock(&bsg_mutex); return 0; -err: - if (class_dev) - class_device_destroy(bsg_class, MKDEV(BSG_MAJOR, bcd->minor)); + +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 int bsg_add(struct class_device *cl_dev, struct class_interface *cl_intf) -{ - int ret; - struct scsi_device *sdp = to_scsi_device(cl_dev->dev); - struct request_queue *rq = sdp->request_queue; - - if (rq->kobj.parent) - ret = bsg_register_queue(rq, kobject_name(rq->kobj.parent)); - else - ret = bsg_register_queue(rq, kobject_name(&sdp->sdev_gendev.kobj)); - return ret; -} +static struct cdev bsg_cdev; -static void bsg_remove(struct class_device *cl_dev, struct class_interface *cl_intf) +static char *bsg_devnode(struct device *dev, mode_t *mode) { - bsg_unregister_queue(to_scsi_device(cl_dev->dev)->request_queue); + return kasprintf(GFP_KERNEL, "bsg/%s", dev_name(dev)); } -static struct class_interface bsg_intf = { - .add = bsg_add, - .remove = bsg_remove, -}; - -static struct cdev bsg_cdev = { - .kobj = {.name = "bsg", }, - .owner = THIS_MODULE, -}; - static int __init bsg_init(void) { int ret, i; + dev_t devid; bsg_cmd_cachep = kmem_cache_create("bsg_cmd", - sizeof(struct bsg_command), 0, 0, NULL, NULL); + 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_SIZE; i++) + 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)) { - kmem_cache_destroy(bsg_cmd_cachep); - return PTR_ERR(bsg_class); + ret = PTR_ERR(bsg_class); + goto destroy_kmemcache; } + bsg_class->devnode = bsg_devnode; - ret = register_chrdev_region(MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS, "bsg"); - if (ret) { - kmem_cache_destroy(bsg_cmd_cachep); - class_destroy(bsg_class); - return ret; - } + ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg"); + if (ret) + goto destroy_bsg_class; - cdev_init(&bsg_cdev, &bsg_fops); - ret = cdev_add(&bsg_cdev, MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS); - if (ret) { - kmem_cache_destroy(bsg_cmd_cachep); - class_destroy(bsg_class); - unregister_chrdev_region(MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS); - return ret; - } + bsg_major = MAJOR(devid); - ret = scsi_register_interface(&bsg_intf); - if (ret) { - printk(KERN_ERR "bsg: failed register scsi interface %d\n", ret); - kmem_cache_destroy(bsg_cmd_cachep); - class_destroy(bsg_class); - unregister_chrdev(BSG_MAJOR, "bsg"); - return ret; - } + 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 "%s loaded\n", bsg_version); + 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"); device_initcall(bsg_init);