On 2016/06/08, 16:50, "James Simmons" <jsimm...@infradead.org> wrote:
>The lloop device was original developed to work around >the lack of direct I/O for the default loop back device. >Also the lloop device greatly out performed the default >loop back device. The lloop hasn't been worked on for >some time and now it no longer out performs the loop >device and loop now supports direct I/O. Since this is >the case we can delete this device. > >Signed-off-by: James Simmons <jsimm...@infradead.org> Reviewed-by: Andreas Dilger <andreas.dil...@intel.com> Cheers, Andreas >--- > drivers/staging/lustre/lustre/Kconfig | 6 - > drivers/staging/lustre/lustre/llite/Makefile | 3 - > drivers/staging/lustre/lustre/llite/lloop.c | 883 -------------------------- > 3 files changed, 0 insertions(+), 892 deletions(-) > delete mode 100644 drivers/staging/lustre/lustre/llite/lloop.c > >diff --git a/drivers/staging/lustre/lustre/Kconfig >b/drivers/staging/lustre/lustre/Kconfig >index 8ac7cd4..9f5d75f 100644 >--- a/drivers/staging/lustre/lustre/Kconfig >+++ b/drivers/staging/lustre/lustre/Kconfig >@@ -54,9 +54,3 @@ config LUSTRE_TRANSLATE_ERRNOS > bool > depends on LUSTRE_FS && !X86 > default y >- >-config LUSTRE_LLITE_LLOOP >- tristate "Lustre virtual block device" >- depends on LUSTRE_FS && BLOCK >- depends on !PPC_64K_PAGES && !ARM64_64K_PAGES && !MICROBLAZE_64K_PAGES >&& !PAGE_SIZE_64KB && !IA64_PAGE_SIZE_64KB && !PARISC_PAGE_SIZE_64KB >- default m >diff --git a/drivers/staging/lustre/lustre/llite/Makefile >b/drivers/staging/lustre/lustre/llite/Makefile >index 2ce10ff..19701e7 100644 >--- a/drivers/staging/lustre/lustre/llite/Makefile >+++ b/drivers/staging/lustre/lustre/llite/Makefile >@@ -1,5 +1,4 @@ > obj-$(CONFIG_LUSTRE_FS) += lustre.o >-obj-$(CONFIG_LUSTRE_LLITE_LLOOP) += llite_lloop.o > lustre-y := dcache.o dir.o file.o llite_close.o llite_lib.o llite_nfs.o \ > rw.o namei.o symlink.o llite_mmap.o \ > xattr.o xattr_cache.o remote_perm.o llite_rmtacl.o \ >@@ -7,5 +6,3 @@ lustre-y := dcache.o dir.o file.o llite_close.o llite_lib.o >llite_nfs.o \ > glimpse.o lcommon_cl.o lcommon_misc.o \ > vvp_dev.o vvp_page.o vvp_lock.o vvp_io.o vvp_object.o vvp_req.o \ > lproc_llite.o >- >-llite_lloop-y := lloop.o >diff --git a/drivers/staging/lustre/lustre/llite/lloop.c >b/drivers/staging/lustre/lustre/llite/lloop.c >deleted file mode 100644 >index 813a9a3..0000000 >--- 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.renard...@waw.com Mar 20, >1997 >- * >- * Added devfs support - Richard Gooch <rgo...@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 <rkr...@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?, <er...@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 <ax...@suse.de>, Nov 2000 >- * >- * Support up to 256 loop devices >- * Heinz Mauelshagen <m...@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); >-- >1.7.1 > > _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
