diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/llite/lloop.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/llite/lloop.c | 883 |
1 files changed, 0 insertions, 883 deletions
diff --git a/drivers/staging/lustre/lustre/llite/lloop.c b/drivers/staging/lustre/lustre/llite/lloop.c deleted file mode 100644 index 813a9a354..000000000 --- a/drivers/staging/lustre/lustre/llite/lloop.c +++ /dev/null @@ -1,883 +0,0 @@ -/* - * GPL HEADER START - * - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 only, - * as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License version 2 for more details (a copy is included - * in the LICENSE file that accompanied this code). - * - * You should have received a copy of the GNU General Public License - * version 2 along with this program; If not, see - * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf - * - * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, - * CA 95054 USA or visit www.sun.com if you need additional information or - * have any questions. - * - * GPL HEADER END - */ -/* - * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. - * Use is subject to license terms. - * - * Copyright (c) 2011, 2012, Intel Corporation. - */ -/* - * This file is part of Lustre, http://www.lustre.org/ - * Lustre is a trademark of Sun Microsystems, Inc. - */ - -/* - * linux/drivers/block/loop.c - * - * Written by Theodore Ts'o, 3/29/93 - * - * Copyright 1993 by Theodore Ts'o. Redistribution of this file is - * permitted under the GNU General Public License. - * - * Modularized and updated for 1.1.16 kernel - Mitch Dsouza 28th May 1994 - * Adapted for 1.3.59 kernel - Andries Brouwer, 1 Feb 1996 - * - * Fixed do_loop_request() re-entrancy - Vincent.Renardias@waw.com Mar 20, 1997 - * - * Added devfs support - Richard Gooch <rgooch@atnf.csiro.au> 16-Jan-1998 - * - * Handle sparse backing files correctly - Kenn Humborg, Jun 28, 1998 - * - * Loadable modules and other fixes by AK, 1998 - * - * Maximum number of loop devices now dynamic via max_loop module parameter. - * Russell Kroll <rkroll@exploits.org> 19990701 - * - * Maximum number of loop devices when compiled-in now selectable by passing - * max_loop=<1-255> to the kernel on boot. - * Erik I. Bols?, <eriki@himolde.no>, Oct 31, 1999 - * - * Completely rewrite request handling to be make_request_fn style and - * non blocking, pushing work to a helper thread. Lots of fixes from - * Al Viro too. - * Jens Axboe <axboe@suse.de>, Nov 2000 - * - * Support up to 256 loop devices - * Heinz Mauelshagen <mge@sistina.com>, Feb 2002 - * - * Support for falling back on the write file operation when the address space - * operations prepare_write and/or commit_write are not available on the - * backing filesystem. - * Anton Altaparmakov, 16 Feb 2005 - * - * Still To Fix: - * - Advisory locking is ignored here. - * - Should use an own CAP_* category instead of CAP_SYS_ADMIN - * - */ - -#include <linux/module.h> - -#include <linux/sched.h> -#include <linux/fs.h> -#include <linux/file.h> -#include <linux/stat.h> -#include <linux/errno.h> -#include <linux/major.h> -#include <linux/wait.h> -#include <linux/blkdev.h> -#include <linux/blkpg.h> -#include <linux/init.h> -#include <linux/swap.h> -#include <linux/slab.h> -#include <linux/suspend.h> -#include <linux/writeback.h> -#include <linux/buffer_head.h> /* for invalidate_bdev() */ -#include <linux/completion.h> -#include <linux/highmem.h> -#include <linux/gfp.h> -#include <linux/pagevec.h> -#include <linux/uaccess.h> - -#include "../include/lustre_lib.h" -#include "../include/lustre_lite.h" -#include "llite_internal.h" - -#define LLOOP_MAX_SEGMENTS LNET_MAX_IOV - -/* Possible states of device */ -enum { - LLOOP_UNBOUND, - LLOOP_BOUND, - LLOOP_RUNDOWN, -}; - -struct lloop_device { - int lo_number; - int lo_refcnt; - loff_t lo_offset; - loff_t lo_sizelimit; - int lo_flags; - struct file *lo_backing_file; - struct block_device *lo_device; - unsigned lo_blocksize; - - gfp_t old_gfp_mask; - - spinlock_t lo_lock; - struct bio *lo_bio; - struct bio *lo_biotail; - int lo_state; - struct semaphore lo_sem; - struct mutex lo_ctl_mutex; - atomic_t lo_pending; - wait_queue_head_t lo_bh_wait; - - struct request_queue *lo_queue; - - const struct lu_env *lo_env; - struct cl_io lo_io; - struct ll_dio_pages lo_pvec; - - /* data to handle bio for lustre. */ - struct lo_request_data { - struct page *lrd_pages[LLOOP_MAX_SEGMENTS]; - loff_t lrd_offsets[LLOOP_MAX_SEGMENTS]; - } lo_requests[1]; -}; - -/* - * Loop flags - */ -enum { - LO_FLAGS_READ_ONLY = 1, -}; - -static int lloop_major; -#define MAX_LOOP_DEFAULT 16 -static int max_loop = MAX_LOOP_DEFAULT; -static struct lloop_device *loop_dev; -static struct gendisk **disks; -static struct mutex lloop_mutex; -static void *ll_iocontrol_magic; - -static loff_t get_loop_size(struct lloop_device *lo, struct file *file) -{ - loff_t size, offset, loopsize; - - /* Compute loopsize in bytes */ - size = i_size_read(file->f_mapping->host); - offset = lo->lo_offset; - loopsize = size - offset; - if (lo->lo_sizelimit > 0 && lo->lo_sizelimit < loopsize) - loopsize = lo->lo_sizelimit; - - /* - * Unfortunately, if we want to do I/O on the device, - * the number of 512-byte sectors has to fit into a sector_t. - */ - return loopsize >> 9; -} - -static int do_bio_lustrebacked(struct lloop_device *lo, struct bio *head) -{ - const struct lu_env *env = lo->lo_env; - struct cl_io *io = &lo->lo_io; - struct inode *inode = file_inode(lo->lo_backing_file); - struct cl_object *obj = ll_i2info(inode)->lli_clob; - pgoff_t offset; - int ret; - int rw; - u32 page_count = 0; - struct bio_vec bvec; - struct bvec_iter iter; - struct bio *bio; - ssize_t bytes; - - struct ll_dio_pages *pvec = &lo->lo_pvec; - struct page **pages = pvec->ldp_pages; - loff_t *offsets = pvec->ldp_offsets; - - truncate_inode_pages(inode->i_mapping, 0); - - /* initialize the IO */ - memset(io, 0, sizeof(*io)); - io->ci_obj = obj; - ret = cl_io_init(env, io, CIT_MISC, obj); - if (ret) - return io->ci_result; - io->ci_lockreq = CILR_NEVER; - - rw = head->bi_rw; - for (bio = head; bio ; bio = bio->bi_next) { - LASSERT(rw == bio->bi_rw); - - offset = (pgoff_t)(bio->bi_iter.bi_sector << 9) + lo->lo_offset; - bio_for_each_segment(bvec, bio, iter) { - BUG_ON(bvec.bv_offset != 0); - BUG_ON(bvec.bv_len != PAGE_SIZE); - - pages[page_count] = bvec.bv_page; - offsets[page_count] = offset; - page_count++; - offset += bvec.bv_len; - } - LASSERT(page_count <= LLOOP_MAX_SEGMENTS); - } - - ll_stats_ops_tally(ll_i2sbi(inode), - (rw == WRITE) ? LPROC_LL_BRW_WRITE : LPROC_LL_BRW_READ, - page_count); - - pvec->ldp_size = page_count << PAGE_SHIFT; - pvec->ldp_nr = page_count; - - /* FIXME: in ll_direct_rw_pages, it has to allocate many cl_page{}s to - * write those pages into OST. Even worse case is that more pages - * would be asked to write out to swap space, and then finally get here - * again. - * Unfortunately this is NOT easy to fix. - * Thoughts on solution: - * 0. Define a reserved pool for cl_pages, which could be a list of - * pre-allocated cl_pages; - * 1. Define a new operation in cl_object_operations{}, says clo_depth, - * which measures how many layers for this lustre object. Generally - * speaking, the depth would be 2, one for llite, and one for lovsub. - * However, for SNS, there will be more since we need additional page - * to store parity; - * 2. Reserve the # of (page_count * depth) cl_pages from the reserved - * pool. Afterwards, the clio would allocate the pages from reserved - * pool, this guarantees we needn't allocate the cl_pages from - * generic cl_page slab cache. - * Of course, if there is NOT enough pages in the pool, we might - * be asked to write less pages once, this purely depends on - * implementation. Anyway, we should be careful to avoid deadlocking. - */ - inode_lock(inode); - bytes = ll_direct_rw_pages(env, io, rw, inode, pvec); - inode_unlock(inode); - cl_io_fini(env, io); - return (bytes == pvec->ldp_size) ? 0 : (int)bytes; -} - -/* - * Add bio to back of pending list - */ -static void loop_add_bio(struct lloop_device *lo, struct bio *bio) -{ - unsigned long flags; - - spin_lock_irqsave(&lo->lo_lock, flags); - if (lo->lo_biotail) { - lo->lo_biotail->bi_next = bio; - lo->lo_biotail = bio; - } else { - lo->lo_bio = lo->lo_biotail = bio; - } - spin_unlock_irqrestore(&lo->lo_lock, flags); - - atomic_inc(&lo->lo_pending); - if (waitqueue_active(&lo->lo_bh_wait)) - wake_up(&lo->lo_bh_wait); -} - -/* - * Grab first pending buffer - */ -static unsigned int loop_get_bio(struct lloop_device *lo, struct bio **req) -{ - struct bio *first; - struct bio **bio; - unsigned int count = 0; - unsigned int page_count = 0; - int rw; - - spin_lock_irq(&lo->lo_lock); - first = lo->lo_bio; - if (unlikely(!first)) { - spin_unlock_irq(&lo->lo_lock); - return 0; - } - - /* TODO: need to split the bio, too bad. */ - LASSERT(first->bi_vcnt <= LLOOP_MAX_SEGMENTS); - - rw = first->bi_rw; - bio = &lo->lo_bio; - while (*bio && (*bio)->bi_rw == rw) { - CDEBUG(D_INFO, "bio sector %llu size %u count %u vcnt%u\n", - (unsigned long long)(*bio)->bi_iter.bi_sector, - (*bio)->bi_iter.bi_size, - page_count, (*bio)->bi_vcnt); - if (page_count + (*bio)->bi_vcnt > LLOOP_MAX_SEGMENTS) - break; - - page_count += (*bio)->bi_vcnt; - count++; - bio = &(*bio)->bi_next; - } - if (*bio) { - /* Some of bios can't be mergeable. */ - lo->lo_bio = *bio; - *bio = NULL; - } else { - /* Hit the end of queue */ - lo->lo_biotail = NULL; - lo->lo_bio = NULL; - } - *req = first; - spin_unlock_irq(&lo->lo_lock); - return count; -} - -static blk_qc_t loop_make_request(struct request_queue *q, struct bio *old_bio) -{ - struct lloop_device *lo = q->queuedata; - int rw = bio_rw(old_bio); - int inactive; - - blk_queue_split(q, &old_bio, q->bio_split); - - if (!lo) - goto err; - - CDEBUG(D_INFO, "submit bio sector %llu size %u\n", - (unsigned long long)old_bio->bi_iter.bi_sector, - old_bio->bi_iter.bi_size); - - spin_lock_irq(&lo->lo_lock); - inactive = lo->lo_state != LLOOP_BOUND; - spin_unlock_irq(&lo->lo_lock); - if (inactive) - goto err; - - if (rw == WRITE) { - if (lo->lo_flags & LO_FLAGS_READ_ONLY) - goto err; - } else if (rw == READA) { - rw = READ; - } else if (rw != READ) { - CERROR("lloop: unknown command (%x)\n", rw); - goto err; - } - loop_add_bio(lo, old_bio); - return BLK_QC_T_NONE; -err: - bio_io_error(old_bio); - return BLK_QC_T_NONE; -} - -static inline void loop_handle_bio(struct lloop_device *lo, struct bio *bio) -{ - int ret; - - ret = do_bio_lustrebacked(lo, bio); - while (bio) { - struct bio *tmp = bio->bi_next; - - bio->bi_next = NULL; - bio->bi_error = ret; - bio_endio(bio); - bio = tmp; - } -} - -static inline int loop_active(struct lloop_device *lo) -{ - return atomic_read(&lo->lo_pending) || - (lo->lo_state == LLOOP_RUNDOWN); -} - -/* - * worker thread that handles reads/writes to file backed loop devices, - * to avoid blocking in our make_request_fn. - */ -static int loop_thread(void *data) -{ - struct lloop_device *lo = data; - struct bio *bio; - unsigned int count; - unsigned long times = 0; - unsigned long total_count = 0; - - struct lu_env *env; - int refcheck; - int ret = 0; - - set_user_nice(current, MIN_NICE); - - lo->lo_state = LLOOP_BOUND; - - env = cl_env_get(&refcheck); - if (IS_ERR(env)) { - ret = PTR_ERR(env); - goto out; - } - - lo->lo_env = env; - memset(&lo->lo_pvec, 0, sizeof(lo->lo_pvec)); - lo->lo_pvec.ldp_pages = lo->lo_requests[0].lrd_pages; - lo->lo_pvec.ldp_offsets = lo->lo_requests[0].lrd_offsets; - - /* - * up sem, we are running - */ - up(&lo->lo_sem); - - for (;;) { - wait_event(lo->lo_bh_wait, loop_active(lo)); - if (!atomic_read(&lo->lo_pending)) { - int exiting = 0; - - spin_lock_irq(&lo->lo_lock); - exiting = (lo->lo_state == LLOOP_RUNDOWN); - spin_unlock_irq(&lo->lo_lock); - if (exiting) - break; - } - - bio = NULL; - count = loop_get_bio(lo, &bio); - if (!count) { - CWARN("lloop(minor: %d): missing bio\n", lo->lo_number); - continue; - } - - total_count += count; - if (total_count < count) { /* overflow */ - total_count = count; - times = 1; - } else { - times++; - } - if ((times & 127) == 0) { - CDEBUG(D_INFO, "total: %lu, count: %lu, avg: %lu\n", - total_count, times, total_count / times); - } - - LASSERT(bio); - LASSERT(count <= atomic_read(&lo->lo_pending)); - loop_handle_bio(lo, bio); - atomic_sub(count, &lo->lo_pending); - } - cl_env_put(env, &refcheck); - -out: - up(&lo->lo_sem); - return ret; -} - -static int loop_set_fd(struct lloop_device *lo, struct file *unused, - struct block_device *bdev, struct file *file) -{ - struct inode *inode; - struct address_space *mapping; - int lo_flags = 0; - int error; - loff_t size; - - if (!try_module_get(THIS_MODULE)) - return -ENODEV; - - error = -EBUSY; - if (lo->lo_state != LLOOP_UNBOUND) - goto out; - - mapping = file->f_mapping; - inode = mapping->host; - - error = -EINVAL; - if (!S_ISREG(inode->i_mode) || inode->i_sb->s_magic != LL_SUPER_MAGIC) - goto out; - - if (!(file->f_mode & FMODE_WRITE)) - lo_flags |= LO_FLAGS_READ_ONLY; - - size = get_loop_size(lo, file); - - if ((loff_t)(sector_t)size != size) { - error = -EFBIG; - goto out; - } - - /* remove all pages in cache so as dirty pages not to be existent. */ - truncate_inode_pages(mapping, 0); - - set_device_ro(bdev, (lo_flags & LO_FLAGS_READ_ONLY) != 0); - - lo->lo_blocksize = PAGE_SIZE; - lo->lo_device = bdev; - lo->lo_flags = lo_flags; - lo->lo_backing_file = file; - lo->lo_sizelimit = 0; - lo->old_gfp_mask = mapping_gfp_mask(mapping); - mapping_set_gfp_mask(mapping, lo->old_gfp_mask & ~(__GFP_IO|__GFP_FS)); - - lo->lo_bio = lo->lo_biotail = NULL; - - /* - * set queue make_request_fn, and add limits based on lower level - * device - */ - blk_queue_make_request(lo->lo_queue, loop_make_request); - lo->lo_queue->queuedata = lo; - - /* queue parameters */ - CLASSERT(PAGE_SIZE < (1 << (sizeof(unsigned short) * 8))); - blk_queue_logical_block_size(lo->lo_queue, - (unsigned short)PAGE_SIZE); - blk_queue_max_hw_sectors(lo->lo_queue, - LLOOP_MAX_SEGMENTS << (PAGE_SHIFT - 9)); - blk_queue_max_segments(lo->lo_queue, LLOOP_MAX_SEGMENTS); - - set_capacity(disks[lo->lo_number], size); - bd_set_size(bdev, size << 9); - - set_blocksize(bdev, lo->lo_blocksize); - - kthread_run(loop_thread, lo, "lloop%d", lo->lo_number); - down(&lo->lo_sem); - return 0; - -out: - /* This is safe: open() is still holding a reference. */ - module_put(THIS_MODULE); - return error; -} - -static int loop_clr_fd(struct lloop_device *lo, struct block_device *bdev, - int count) -{ - struct file *filp = lo->lo_backing_file; - gfp_t gfp = lo->old_gfp_mask; - - if (lo->lo_state != LLOOP_BOUND) - return -ENXIO; - - if (lo->lo_refcnt > count) /* we needed one fd for the ioctl */ - return -EBUSY; - - if (!filp) - return -EINVAL; - - spin_lock_irq(&lo->lo_lock); - lo->lo_state = LLOOP_RUNDOWN; - spin_unlock_irq(&lo->lo_lock); - wake_up(&lo->lo_bh_wait); - - down(&lo->lo_sem); - lo->lo_backing_file = NULL; - lo->lo_device = NULL; - lo->lo_offset = 0; - lo->lo_sizelimit = 0; - lo->lo_flags = 0; - invalidate_bdev(bdev); - set_capacity(disks[lo->lo_number], 0); - bd_set_size(bdev, 0); - mapping_set_gfp_mask(filp->f_mapping, gfp); - lo->lo_state = LLOOP_UNBOUND; - fput(filp); - /* This is safe: open() is still holding a reference. */ - module_put(THIS_MODULE); - return 0; -} - -static int lo_open(struct block_device *bdev, fmode_t mode) -{ - struct lloop_device *lo = bdev->bd_disk->private_data; - - mutex_lock(&lo->lo_ctl_mutex); - lo->lo_refcnt++; - mutex_unlock(&lo->lo_ctl_mutex); - - return 0; -} - -static void lo_release(struct gendisk *disk, fmode_t mode) -{ - struct lloop_device *lo = disk->private_data; - - mutex_lock(&lo->lo_ctl_mutex); - --lo->lo_refcnt; - mutex_unlock(&lo->lo_ctl_mutex); -} - -/* lloop device node's ioctl function. */ -static int lo_ioctl(struct block_device *bdev, fmode_t mode, - unsigned int cmd, unsigned long arg) -{ - struct lloop_device *lo = bdev->bd_disk->private_data; - struct inode *inode = NULL; - int err = 0; - - mutex_lock(&lloop_mutex); - switch (cmd) { - case LL_IOC_LLOOP_DETACH: { - err = loop_clr_fd(lo, bdev, 2); - if (err == 0) - blkdev_put(bdev, 0); /* grabbed in LLOOP_ATTACH */ - break; - } - - case LL_IOC_LLOOP_INFO: { - struct lu_fid fid; - - if (!lo->lo_backing_file) { - err = -ENOENT; - break; - } - if (!inode) - inode = file_inode(lo->lo_backing_file); - if (lo->lo_state == LLOOP_BOUND) - fid = ll_i2info(inode)->lli_fid; - else - fid_zero(&fid); - - if (copy_to_user((void __user *)arg, &fid, sizeof(fid))) - err = -EFAULT; - break; - } - - default: - err = -EINVAL; - break; - } - mutex_unlock(&lloop_mutex); - - return err; -} - -static struct block_device_operations lo_fops = { - .owner = THIS_MODULE, - .open = lo_open, - .release = lo_release, - .ioctl = lo_ioctl, -}; - -/* dynamic iocontrol callback. - * This callback is registered in lloop_init and will be called by - * ll_iocontrol_call. - * - * This is a llite regular file ioctl function. It takes the responsibility - * of attaching or detaching a file by a lloop's device number. - */ -static enum llioc_iter lloop_ioctl(struct inode *unused, struct file *file, - unsigned int cmd, unsigned long arg, - void *magic, int *rcp) -{ - struct lloop_device *lo = NULL; - struct block_device *bdev = NULL; - int err = 0; - dev_t dev; - - if (magic != ll_iocontrol_magic) - return LLIOC_CONT; - - if (!disks) { - err = -ENODEV; - goto out1; - } - - CWARN("Enter llop_ioctl\n"); - - mutex_lock(&lloop_mutex); - switch (cmd) { - case LL_IOC_LLOOP_ATTACH: { - struct lloop_device *lo_free = NULL; - int i; - - for (i = 0; i < max_loop; i++, lo = NULL) { - lo = &loop_dev[i]; - if (lo->lo_state == LLOOP_UNBOUND) { - if (!lo_free) - lo_free = lo; - continue; - } - if (file_inode(lo->lo_backing_file) == file_inode(file)) - break; - } - if (lo || !lo_free) { - err = -EBUSY; - goto out; - } - - lo = lo_free; - dev = MKDEV(lloop_major, lo->lo_number); - - /* quit if the used pointer is writable */ - if (put_user((long)old_encode_dev(dev), (long __user *)arg)) { - err = -EFAULT; - goto out; - } - - bdev = blkdev_get_by_dev(dev, file->f_mode, NULL); - if (IS_ERR(bdev)) { - err = PTR_ERR(bdev); - goto out; - } - - get_file(file); - err = loop_set_fd(lo, NULL, bdev, file); - if (err) { - fput(file); - blkdev_put(bdev, 0); - } - - break; - } - - case LL_IOC_LLOOP_DETACH_BYDEV: { - int minor; - - dev = old_decode_dev(arg); - if (MAJOR(dev) != lloop_major) { - err = -EINVAL; - goto out; - } - - minor = MINOR(dev); - if (minor > max_loop - 1) { - err = -EINVAL; - goto out; - } - - lo = &loop_dev[minor]; - if (lo->lo_state != LLOOP_BOUND) { - err = -EINVAL; - goto out; - } - - bdev = lo->lo_device; - err = loop_clr_fd(lo, bdev, 1); - if (err == 0) - blkdev_put(bdev, 0); /* grabbed in LLOOP_ATTACH */ - - break; - } - - default: - err = -EINVAL; - break; - } - -out: - mutex_unlock(&lloop_mutex); -out1: - if (rcp) - *rcp = err; - return LLIOC_STOP; -} - -static int __init lloop_init(void) -{ - int i; - unsigned int cmdlist[] = { - LL_IOC_LLOOP_ATTACH, - LL_IOC_LLOOP_DETACH_BYDEV, - }; - - if (max_loop < 1 || max_loop > 256) { - max_loop = MAX_LOOP_DEFAULT; - CWARN("lloop: invalid max_loop (must be between 1 and 256), using default (%u)\n", - max_loop); - } - - lloop_major = register_blkdev(0, "lloop"); - if (lloop_major < 0) - return -EIO; - - CDEBUG(D_CONFIG, "registered lloop major %d with %u minors\n", - lloop_major, max_loop); - - ll_iocontrol_magic = ll_iocontrol_register(lloop_ioctl, 2, cmdlist); - if (!ll_iocontrol_magic) - goto out_mem1; - - loop_dev = kcalloc(max_loop, sizeof(*loop_dev), GFP_KERNEL); - if (!loop_dev) - goto out_mem1; - - disks = kcalloc(max_loop, sizeof(*disks), GFP_KERNEL); - if (!disks) - goto out_mem2; - - for (i = 0; i < max_loop; i++) { - disks[i] = alloc_disk(1); - if (!disks[i]) - goto out_mem3; - } - - mutex_init(&lloop_mutex); - - for (i = 0; i < max_loop; i++) { - struct lloop_device *lo = &loop_dev[i]; - struct gendisk *disk = disks[i]; - - lo->lo_queue = blk_alloc_queue(GFP_KERNEL); - if (!lo->lo_queue) - goto out_mem4; - - mutex_init(&lo->lo_ctl_mutex); - sema_init(&lo->lo_sem, 0); - init_waitqueue_head(&lo->lo_bh_wait); - lo->lo_number = i; - spin_lock_init(&lo->lo_lock); - disk->major = lloop_major; - disk->first_minor = i; - disk->fops = &lo_fops; - sprintf(disk->disk_name, "lloop%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]); - 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: - unregister_blkdev(lloop_major, "lloop"); - ll_iocontrol_unregister(ll_iocontrol_magic); - CERROR("lloop: ran out of memory\n"); - return -ENOMEM; -} - -static void lloop_exit(void) -{ - int i; - - ll_iocontrol_unregister(ll_iocontrol_magic); - for (i = 0; i < max_loop; i++) { - del_gendisk(disks[i]); - blk_cleanup_queue(loop_dev[i].lo_queue); - put_disk(disks[i]); - } - - unregister_blkdev(lloop_major, "lloop"); - - kfree(disks); - kfree(loop_dev); -} - -module_param(max_loop, int, 0444); -MODULE_PARM_DESC(max_loop, "maximum of lloop_device"); -MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>"); -MODULE_DESCRIPTION("Lustre virtual block device"); -MODULE_VERSION(LUSTRE_VERSION_STRING); -MODULE_LICENSE("GPL"); - -module_init(lloop_init); -module_exit(lloop_exit); |