X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=drivers%2Fblock%2Floop.c;h=af6d7274a7cc9a28c84d5bf7a4dfba1b6fdf0789;hb=7e81ab9d3d9a22fb7b20c56f0cabc8ef51954014;hp=68b0471ad5a64e52a2b53135ab58523507fb700d;hpb=9a69d1aeccf169d9a1e442c07d3a6e87f06a7b49;p=powerpc.git diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 68b0471ad5..af6d7274a7 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -66,6 +66,7 @@ #include #include #include +#include #include #include #include /* for invalidate_bdev() */ @@ -76,9 +77,8 @@ #include -static int max_loop = 8; -static struct loop_device *loop_dev; -static struct gendisk **disks; +static LIST_HEAD(loop_devices); +static DEFINE_MUTEX(loop_devices_mutex); /* * Transfer functions @@ -182,7 +182,7 @@ figure_loop_size(struct loop_device *lo) if (unlikely((loff_t)x != size)) return -EFBIG; - set_capacity(disks[lo->lo_number], x); + set_capacity(lo->lo_disk, x); return 0; } @@ -294,7 +294,7 @@ fail: * and do_lo_send_write(). */ static int __do_lo_send_write(struct file *file, - u8 __user *buf, const int len, loff_t pos) + u8 *buf, const int len, loff_t pos) { ssize_t bw; mm_segment_t old_fs = get_fs(); @@ -323,7 +323,7 @@ static int do_lo_send_direct_write(struct loop_device *lo, struct bio_vec *bvec, int bsize, loff_t pos, struct page *page) { ssize_t bw = __do_lo_send_write(lo->lo_backing_file, - (u8 __user *)kmap(bvec->bv_page) + bvec->bv_offset, + kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len, pos); kunmap(bvec->bv_page); cond_resched(); @@ -350,7 +350,7 @@ static int do_lo_send_write(struct loop_device *lo, struct bio_vec *bvec, bvec->bv_offset, bvec->bv_len, pos >> 9); if (likely(!ret)) return __do_lo_send_write(lo->lo_backing_file, - (u8 __user *)page_address(page), bvec->bv_len, + page_address(page), bvec->bv_len, pos); printk(KERN_ERR "loop: Transfer error at byte offset %llu, " "length %i.\n", (unsigned long long)pos, bvec->bv_len); @@ -811,7 +811,7 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file, lo->lo_queue->queuedata = lo; lo->lo_queue->unplug_fn = loop_unplug; - set_capacity(disks[lo->lo_number], size); + set_capacity(lo->lo_disk, size); bd_set_size(bdev, size << 9); set_blocksize(bdev, lo_blocksize); @@ -831,8 +831,8 @@ out_clr: lo->lo_device = NULL; lo->lo_backing_file = NULL; lo->lo_flags = 0; - set_capacity(disks[lo->lo_number], 0); - invalidate_bdev(bdev, 0); + set_capacity(lo->lo_disk, 0); + invalidate_bdev(bdev); bd_set_size(bdev, 0); mapping_set_gfp_mask(mapping, lo->old_gfp_mask); lo->lo_state = Lo_unbound; @@ -916,8 +916,8 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev) memset(lo->lo_encrypt_key, 0, LO_KEY_SIZE); memset(lo->lo_crypt_name, 0, LO_NAME_SIZE); memset(lo->lo_file_name, 0, LO_NAME_SIZE); - invalidate_bdev(bdev, 0); - set_capacity(disks[lo->lo_number], 0); + invalidate_bdev(bdev); + set_capacity(lo->lo_disk, 0); bd_set_size(bdev, 0); mapping_set_gfp_mask(filp->f_mapping, gfp); lo->lo_state = Lo_unbound; @@ -999,7 +999,7 @@ loop_get_status(struct loop_device *lo, struct loop_info64 *info) if (lo->lo_state != Lo_bound) return -ENXIO; - error = vfs_getattr(file->f_vfsmnt, file->f_dentry, &stat); + error = vfs_getattr(file->f_path.mnt, file->f_path.dentry, &stat); if (error) return error; memset(info, 0, sizeof(*info)); @@ -1165,6 +1165,174 @@ static int lo_ioctl(struct inode * inode, struct file * file, return err; } +#ifdef CONFIG_COMPAT +struct compat_loop_info { + compat_int_t lo_number; /* ioctl r/o */ + compat_dev_t lo_device; /* ioctl r/o */ + compat_ulong_t lo_inode; /* ioctl r/o */ + compat_dev_t lo_rdevice; /* ioctl r/o */ + compat_int_t lo_offset; + compat_int_t lo_encrypt_type; + compat_int_t lo_encrypt_key_size; /* ioctl w/o */ + compat_int_t lo_flags; /* ioctl r/o */ + char lo_name[LO_NAME_SIZE]; + unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ + compat_ulong_t lo_init[2]; + char reserved[4]; +}; + +/* + * Transfer 32-bit compatibility structure in userspace to 64-bit loop info + * - noinlined to reduce stack space usage in main part of driver + */ +static noinline int +loop_info64_from_compat(const struct compat_loop_info __user *arg, + struct loop_info64 *info64) +{ + struct compat_loop_info info; + + if (copy_from_user(&info, arg, sizeof(info))) + return -EFAULT; + + memset(info64, 0, sizeof(*info64)); + info64->lo_number = info.lo_number; + info64->lo_device = info.lo_device; + info64->lo_inode = info.lo_inode; + info64->lo_rdevice = info.lo_rdevice; + info64->lo_offset = info.lo_offset; + info64->lo_sizelimit = 0; + info64->lo_encrypt_type = info.lo_encrypt_type; + info64->lo_encrypt_key_size = info.lo_encrypt_key_size; + info64->lo_flags = info.lo_flags; + info64->lo_init[0] = info.lo_init[0]; + info64->lo_init[1] = info.lo_init[1]; + if (info.lo_encrypt_type == LO_CRYPT_CRYPTOAPI) + memcpy(info64->lo_crypt_name, info.lo_name, LO_NAME_SIZE); + else + memcpy(info64->lo_file_name, info.lo_name, LO_NAME_SIZE); + memcpy(info64->lo_encrypt_key, info.lo_encrypt_key, LO_KEY_SIZE); + return 0; +} + +/* + * Transfer 64-bit loop info to 32-bit compatibility structure in userspace + * - noinlined to reduce stack space usage in main part of driver + */ +static noinline int +loop_info64_to_compat(const struct loop_info64 *info64, + struct compat_loop_info __user *arg) +{ + struct compat_loop_info info; + + memset(&info, 0, sizeof(info)); + info.lo_number = info64->lo_number; + info.lo_device = info64->lo_device; + info.lo_inode = info64->lo_inode; + info.lo_rdevice = info64->lo_rdevice; + info.lo_offset = info64->lo_offset; + info.lo_encrypt_type = info64->lo_encrypt_type; + info.lo_encrypt_key_size = info64->lo_encrypt_key_size; + info.lo_flags = info64->lo_flags; + info.lo_init[0] = info64->lo_init[0]; + info.lo_init[1] = info64->lo_init[1]; + if (info.lo_encrypt_type == LO_CRYPT_CRYPTOAPI) + memcpy(info.lo_name, info64->lo_crypt_name, LO_NAME_SIZE); + else + memcpy(info.lo_name, info64->lo_file_name, LO_NAME_SIZE); + memcpy(info.lo_encrypt_key, info64->lo_encrypt_key, LO_KEY_SIZE); + + /* error in case values were truncated */ + if (info.lo_device != info64->lo_device || + info.lo_rdevice != info64->lo_rdevice || + info.lo_inode != info64->lo_inode || + info.lo_offset != info64->lo_offset || + info.lo_init[0] != info64->lo_init[0] || + info.lo_init[1] != info64->lo_init[1]) + return -EOVERFLOW; + + if (copy_to_user(arg, &info, sizeof(info))) + return -EFAULT; + return 0; +} + +static int +loop_set_status_compat(struct loop_device *lo, + const struct compat_loop_info __user *arg) +{ + struct loop_info64 info64; + int ret; + + ret = loop_info64_from_compat(arg, &info64); + if (ret < 0) + return ret; + return loop_set_status(lo, &info64); +} + +static int +loop_get_status_compat(struct loop_device *lo, + struct compat_loop_info __user *arg) +{ + struct loop_info64 info64; + int err = 0; + + if (!arg) + err = -EINVAL; + if (!err) + err = loop_get_status(lo, &info64); + if (!err) + err = loop_info64_to_compat(&info64, arg); + return err; +} + +static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct inode *inode = file->f_path.dentry->d_inode; + struct loop_device *lo = inode->i_bdev->bd_disk->private_data; + int err; + + lock_kernel(); + switch(cmd) { + case LOOP_SET_STATUS: + mutex_lock(&lo->lo_ctl_mutex); + err = loop_set_status_compat( + lo, (const struct compat_loop_info __user *) arg); + mutex_unlock(&lo->lo_ctl_mutex); + break; + case LOOP_GET_STATUS: + mutex_lock(&lo->lo_ctl_mutex); + err = loop_get_status_compat( + lo, (struct compat_loop_info __user *) arg); + mutex_unlock(&lo->lo_ctl_mutex); + break; + case LOOP_CLR_FD: + case LOOP_GET_STATUS64: + case LOOP_SET_STATUS64: + arg = (unsigned long) compat_ptr(arg); + case LOOP_SET_FD: + case LOOP_CHANGE_FD: + err = lo_ioctl(inode, file, cmd, arg); + break; + default: + err = -ENOIOCTLCMD; + break; + } + unlock_kernel(); + return err; +} +#endif + +static struct loop_device *loop_find_dev(int number) +{ + struct loop_device *lo; + + list_for_each_entry(lo, &loop_devices, lo_list) { + if (lo->lo_number == number) + return lo; + } + return NULL; +} + +static struct loop_device *loop_init_one(int i); static int lo_open(struct inode *inode, struct file *file) { struct loop_device *lo = inode->i_bdev->bd_disk->private_data; @@ -1173,6 +1341,11 @@ static int lo_open(struct inode *inode, struct file *file) lo->lo_refcnt++; mutex_unlock(&lo->lo_ctl_mutex); + mutex_lock(&loop_devices_mutex); + if (!loop_find_dev(lo->lo_number + 1)) + loop_init_one(lo->lo_number + 1); + mutex_unlock(&loop_devices_mutex); + return 0; } @@ -1192,13 +1365,17 @@ static struct block_device_operations lo_fops = { .open = lo_open, .release = lo_release, .ioctl = lo_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = lo_compat_ioctl, +#endif }; /* * And now the modules code and kernel interface. */ +static int max_loop; module_param(max_loop, int, 0); -MODULE_PARM_DESC(max_loop, "Maximum number of loop devices (1-256)"); +MODULE_PARM_DESC(max_loop, "obsolete, loop device is created on-demand"); MODULE_LICENSE("GPL"); MODULE_ALIAS_BLOCKDEV_MAJOR(LOOP_MAJOR); @@ -1223,7 +1400,7 @@ int loop_unregister_transfer(int number) xfer_funcs[n] = NULL; - for (lo = &loop_dev[0]; lo < &loop_dev[max_loop]; lo++) { + list_for_each_entry(lo, &loop_devices, lo_list) { mutex_lock(&lo->lo_ctl_mutex); if (lo->lo_encryption == xfer) @@ -1238,91 +1415,110 @@ int loop_unregister_transfer(int number) EXPORT_SYMBOL(loop_register_transfer); EXPORT_SYMBOL(loop_unregister_transfer); -static int __init loop_init(void) +static struct loop_device *loop_init_one(int i) +{ + struct loop_device *lo; + struct gendisk *disk; + + lo = kzalloc(sizeof(*lo), GFP_KERNEL); + if (!lo) + goto out; + + lo->lo_queue = blk_alloc_queue(GFP_KERNEL); + if (!lo->lo_queue) + goto out_free_dev; + + disk = lo->lo_disk = alloc_disk(1); + if (!disk) + goto out_free_queue; + + mutex_init(&lo->lo_ctl_mutex); + lo->lo_number = i; + lo->lo_thread = NULL; + init_waitqueue_head(&lo->lo_event); + spin_lock_init(&lo->lo_lock); + disk->major = LOOP_MAJOR; + disk->first_minor = i; + disk->fops = &lo_fops; + disk->private_data = lo; + disk->queue = lo->lo_queue; + sprintf(disk->disk_name, "loop%d", i); + add_disk(disk); + list_add_tail(&lo->lo_list, &loop_devices); + return lo; + +out_free_queue: + blk_cleanup_queue(lo->lo_queue); +out_free_dev: + kfree(lo); +out: + return ERR_PTR(-ENOMEM); +} + +static void loop_del_one(struct loop_device *lo) { - int i; + del_gendisk(lo->lo_disk); + blk_cleanup_queue(lo->lo_queue); + put_disk(lo->lo_disk); + list_del(&lo->lo_list); + kfree(lo); +} - if (max_loop < 1 || max_loop > 256) { - printk(KERN_WARNING "loop: invalid max_loop (must be between" - " 1 and 256), using default (8)\n"); - max_loop = 8; - } +static struct kobject *loop_probe(dev_t dev, int *part, void *data) +{ + unsigned int number = dev & MINORMASK; + struct loop_device *lo; + + mutex_lock(&loop_devices_mutex); + lo = loop_find_dev(number); + if (lo == NULL) + lo = loop_init_one(number); + mutex_unlock(&loop_devices_mutex); + + *part = 0; + if (IS_ERR(lo)) + return (void *)lo; + else + return &lo->lo_disk->kobj; +} + +static int __init loop_init(void) +{ + struct loop_device *lo; if (register_blkdev(LOOP_MAJOR, "loop")) return -EIO; + blk_register_region(MKDEV(LOOP_MAJOR, 0), 1UL << MINORBITS, + THIS_MODULE, loop_probe, NULL, NULL); - loop_dev = kmalloc(max_loop * sizeof(struct loop_device), GFP_KERNEL); - if (!loop_dev) - goto out_mem1; - memset(loop_dev, 0, max_loop * sizeof(struct loop_device)); + lo = loop_init_one(0); + if (IS_ERR(lo)) + goto out; - disks = kmalloc(max_loop * sizeof(struct gendisk *), GFP_KERNEL); - if (!disks) - goto out_mem2; + if (max_loop) { + printk(KERN_INFO "loop: the max_loop option is obsolete " + "and will be removed in March 2008\n"); - for (i = 0; i < max_loop; i++) { - disks[i] = alloc_disk(1); - if (!disks[i]) - goto out_mem3; } - - for (i = 0; i < max_loop; i++) { - struct loop_device *lo = &loop_dev[i]; - struct gendisk *disk = disks[i]; - - memset(lo, 0, sizeof(*lo)); - lo->lo_queue = blk_alloc_queue(GFP_KERNEL); - if (!lo->lo_queue) - goto out_mem4; - mutex_init(&lo->lo_ctl_mutex); - lo->lo_number = i; - lo->lo_thread = NULL; - init_waitqueue_head(&lo->lo_event); - spin_lock_init(&lo->lo_lock); - disk->major = LOOP_MAJOR; - disk->first_minor = i; - disk->fops = &lo_fops; - sprintf(disk->disk_name, "loop%d", i); - disk->private_data = lo; - disk->queue = lo->lo_queue; - } - - /* We cannot fail after we call this, so another loop!*/ - for (i = 0; i < max_loop; i++) - add_disk(disks[i]); - printk(KERN_INFO "loop: loaded (max %d devices)\n", max_loop); + printk(KERN_INFO "loop: module loaded\n"); return 0; -out_mem4: - while (i--) - blk_cleanup_queue(loop_dev[i].lo_queue); - i = max_loop; -out_mem3: - while (i--) - put_disk(disks[i]); - kfree(disks); -out_mem2: - kfree(loop_dev); -out_mem1: +out: unregister_blkdev(LOOP_MAJOR, "loop"); printk(KERN_ERR "loop: ran out of memory\n"); return -ENOMEM; } -static void loop_exit(void) +static void __exit loop_exit(void) { - int i; + struct loop_device *lo, *next; - for (i = 0; i < max_loop; i++) { - del_gendisk(disks[i]); - blk_cleanup_queue(loop_dev[i].lo_queue); - put_disk(disks[i]); - } + list_for_each_entry_safe(lo, next, &loop_devices, lo_list) + loop_del_one(lo); + + blk_unregister_region(MKDEV(LOOP_MAJOR, 0), 1UL << MINORBITS); if (unregister_blkdev(LOOP_MAJOR, "loop")) printk(KERN_WARNING "loop: cannot unregister blkdev\n"); - - kfree(disks); - kfree(loop_dev); } module_init(loop_init);