Apply patches from Jeff Moyer to fix direct-io oops (rhbz 812129)
This commit is contained in:
parent
e7887c8a48
commit
c9be30821b
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@ -0,0 +1,214 @@
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Fix a crash when block device is read and block size is changed at the same time
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commit b87570f5d349661814b262dd5fc40787700f80d6
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Author: Mikulas Patocka <mpatocka@redhat.com>
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Date: Wed Sep 26 07:46:40 2012 +0200
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Fix a crash when block device is read and block size is changed at the same time
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The kernel may crash when block size is changed and I/O is issued
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simultaneously.
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Because some subsystems (udev or lvm) may read any block device anytime,
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the bug actually puts any code that changes a block device size in
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jeopardy.
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The crash can be reproduced if you place "msleep(1000)" to
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blkdev_get_blocks just before "bh->b_size = max_blocks <<
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inode->i_blkbits;".
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Then, run "dd if=/dev/ram0 of=/dev/null bs=4k count=1 iflag=direct"
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While it is waiting in msleep, run "blockdev --setbsz 2048 /dev/ram0"
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You get a BUG.
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The direct and non-direct I/O is written with the assumption that block
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size does not change. It doesn't seem practical to fix these crashes
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one-by-one there may be many crash possibilities when block size changes
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at a certain place and it is impossible to find them all and verify the
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code.
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This patch introduces a new rw-lock bd_block_size_semaphore. The lock is
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taken for read during I/O. It is taken for write when changing block
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size. Consequently, block size can't be changed while I/O is being
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submitted.
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For asynchronous I/O, the patch only prevents block size change while
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the I/O is being submitted. The block size can change when the I/O is in
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progress or when the I/O is being finished. This is acceptable because
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there are no accesses to block size when asynchronous I/O is being
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finished.
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The patch prevents block size changing while the device is mapped with
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mmap.
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Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
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Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Index: linux-3.6.x86_64/drivers/char/raw.c
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===================================================================
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--- linux-3.6.x86_64.orig/drivers/char/raw.c 2012-11-16 17:12:35.127010280 -0500
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+++ linux-3.6.x86_64/drivers/char/raw.c 2012-11-16 17:12:37.381002516 -0500
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@@ -285,7 +285,7 @@
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static const struct file_operations raw_fops = {
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.read = do_sync_read,
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- .aio_read = generic_file_aio_read,
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+ .aio_read = blkdev_aio_read,
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.write = do_sync_write,
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.aio_write = blkdev_aio_write,
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.fsync = blkdev_fsync,
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Index: linux-3.6.x86_64/fs/block_dev.c
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===================================================================
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--- linux-3.6.x86_64.orig/fs/block_dev.c 2012-11-16 17:12:35.127010280 -0500
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+++ linux-3.6.x86_64/fs/block_dev.c 2012-11-16 17:12:37.381002516 -0500
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@@ -116,6 +116,8 @@
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int set_blocksize(struct block_device *bdev, int size)
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{
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+ struct address_space *mapping;
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+
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/* Size must be a power of two, and between 512 and PAGE_SIZE */
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if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
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return -EINVAL;
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@@ -124,6 +126,20 @@
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if (size < bdev_logical_block_size(bdev))
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return -EINVAL;
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+ /* Prevent starting I/O or mapping the device */
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+ down_write(&bdev->bd_block_size_semaphore);
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+
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+ /* Check that the block device is not memory mapped */
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+ mapping = bdev->bd_inode->i_mapping;
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+ mutex_lock(&mapping->i_mmap_mutex);
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+ if (!prio_tree_empty(&mapping->i_mmap) ||
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+ !list_empty(&mapping->i_mmap_nonlinear)) {
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+ mutex_unlock(&mapping->i_mmap_mutex);
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+ up_write(&bdev->bd_block_size_semaphore);
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+ return -EBUSY;
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+ }
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+ mutex_unlock(&mapping->i_mmap_mutex);
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+
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/* Don't change the size if it is same as current */
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if (bdev->bd_block_size != size) {
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sync_blockdev(bdev);
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@@ -131,6 +147,9 @@
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bdev->bd_inode->i_blkbits = blksize_bits(size);
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kill_bdev(bdev);
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}
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+
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+ up_write(&bdev->bd_block_size_semaphore);
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+
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return 0;
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}
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@@ -472,6 +491,7 @@
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inode_init_once(&ei->vfs_inode);
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/* Initialize mutex for freeze. */
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mutex_init(&bdev->bd_fsfreeze_mutex);
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+ init_rwsem(&bdev->bd_block_size_semaphore);
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}
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static inline void __bd_forget(struct inode *inode)
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@@ -1567,6 +1587,22 @@
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return blkdev_ioctl(bdev, mode, cmd, arg);
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}
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+ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
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+ unsigned long nr_segs, loff_t pos)
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+{
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+ ssize_t ret;
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+ struct block_device *bdev = I_BDEV(iocb->ki_filp->f_mapping->host);
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+
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+ down_read(&bdev->bd_block_size_semaphore);
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+
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+ ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
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+
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+ up_read(&bdev->bd_block_size_semaphore);
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+
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+ return ret;
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+}
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+EXPORT_SYMBOL_GPL(blkdev_aio_read);
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+
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/*
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* Write data to the block device. Only intended for the block device itself
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* and the raw driver which basically is a fake block device.
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@@ -1578,12 +1614,16 @@
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unsigned long nr_segs, loff_t pos)
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{
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struct file *file = iocb->ki_filp;
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+ struct block_device *bdev = I_BDEV(file->f_mapping->host);
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struct blk_plug plug;
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ssize_t ret;
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BUG_ON(iocb->ki_pos != pos);
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blk_start_plug(&plug);
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+
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+ down_read(&bdev->bd_block_size_semaphore);
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+
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ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
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if (ret > 0 || ret == -EIOCBQUEUED) {
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ssize_t err;
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@@ -1592,11 +1632,29 @@
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if (err < 0 && ret > 0)
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ret = err;
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}
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+
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+ up_read(&bdev->bd_block_size_semaphore);
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+
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blk_finish_plug(&plug);
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+
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return ret;
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}
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EXPORT_SYMBOL_GPL(blkdev_aio_write);
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+int blkdev_mmap(struct file *file, struct vm_area_struct *vma)
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+{
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+ int ret;
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+ struct block_device *bdev = I_BDEV(file->f_mapping->host);
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+
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+ down_read(&bdev->bd_block_size_semaphore);
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+
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+ ret = generic_file_mmap(file, vma);
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+
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+ up_read(&bdev->bd_block_size_semaphore);
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+
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+ return ret;
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+}
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+
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/*
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* Try to release a page associated with block device when the system
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* is under memory pressure.
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@@ -1627,9 +1685,9 @@
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.llseek = block_llseek,
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.read = do_sync_read,
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.write = do_sync_write,
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- .aio_read = generic_file_aio_read,
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+ .aio_read = blkdev_aio_read,
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.aio_write = blkdev_aio_write,
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- .mmap = generic_file_mmap,
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+ .mmap = blkdev_mmap,
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.fsync = blkdev_fsync,
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.unlocked_ioctl = block_ioctl,
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#ifdef CONFIG_COMPAT
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Index: linux-3.6.x86_64/include/linux/fs.h
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===================================================================
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--- linux-3.6.x86_64.orig/include/linux/fs.h 2012-11-16 17:12:35.127010280 -0500
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+++ linux-3.6.x86_64/include/linux/fs.h 2012-11-16 17:12:37.424002387 -0500
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@@ -724,6 +724,8 @@
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int bd_fsfreeze_count;
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/* Mutex for freeze */
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struct mutex bd_fsfreeze_mutex;
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+ /* A semaphore that prevents I/O while block size is being changed */
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+ struct rw_semaphore bd_block_size_semaphore;
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};
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/*
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@@ -2564,6 +2566,8 @@
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unsigned long *nr_segs, size_t *count, int access_flags);
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/* fs/block_dev.c */
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+extern ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
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+ unsigned long nr_segs, loff_t pos);
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extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
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unsigned long nr_segs, loff_t pos);
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extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
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@ -0,0 +1,290 @@
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blockdev: turn a rw semaphore into a percpu rw semaphore
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commit 62ac665ff9fc07497ca524bd20d6a96893d11071
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Author: Mikulas Patocka <mpatocka@redhat.com>
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Date: Wed Sep 26 07:46:43 2012 +0200
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blockdev: turn a rw semaphore into a percpu rw semaphore
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This avoids cache line bouncing when many processes lock the semaphore
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for read.
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New percpu lock implementation
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The lock consists of an array of percpu unsigned integers, a boolean
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variable and a mutex.
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When we take the lock for read, we enter rcu read section, check for a
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"locked" variable. If it is false, we increase a percpu counter on the
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current cpu and exit the rcu section. If "locked" is true, we exit the
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rcu section, take the mutex and drop it (this waits until a writer
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finished) and retry.
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Unlocking for read just decreases percpu variable. Note that we can
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unlock on a difference cpu than where we locked, in this case the
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counter underflows. The sum of all percpu counters represents the number
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of processes that hold the lock for read.
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When we need to lock for write, we take the mutex, set "locked" variable
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to true and synchronize rcu. Since RCU has been synchronized, no
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processes can create new read locks. We wait until the sum of percpu
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counters is zero - when it is, there are no readers in the critical
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section.
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Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
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Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Index: linux-3.6.x86_64/Documentation/percpu-rw-semaphore.txt
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===================================================================
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--- /dev/null 1970-01-01 00:00:00.000000000 +0000
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+++ linux-3.6.x86_64/Documentation/percpu-rw-semaphore.txt 2012-11-16 17:12:57.351936583 -0500
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@@ -0,0 +1,27 @@
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+Percpu rw semaphores
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+--------------------
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+
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+Percpu rw semaphores is a new read-write semaphore design that is
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+optimized for locking for reading.
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+
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+The problem with traditional read-write semaphores is that when multiple
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+cores take the lock for reading, the cache line containing the semaphore
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+is bouncing between L1 caches of the cores, causing performance
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+degradation.
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+
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+Locking for reading it very fast, it uses RCU and it avoids any atomic
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+instruction in the lock and unlock path. On the other hand, locking for
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+writing is very expensive, it calls synchronize_rcu() that can take
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+hundreds of microseconds.
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+
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+The lock is declared with "struct percpu_rw_semaphore" type.
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+The lock is initialized percpu_init_rwsem, it returns 0 on success and
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+-ENOMEM on allocation failure.
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+The lock must be freed with percpu_free_rwsem to avoid memory leak.
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+
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+The lock is locked for read with percpu_down_read, percpu_up_read and
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+for write with percpu_down_write, percpu_up_write.
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+
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+The idea of using RCU for optimized rw-lock was introduced by
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+Eric Dumazet <eric.dumazet@gmail.com>.
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+The code was written by Mikulas Patocka <mpatocka@redhat.com>
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Index: linux-3.6.x86_64/fs/block_dev.c
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===================================================================
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--- linux-3.6.x86_64.orig/fs/block_dev.c 2012-11-16 17:12:37.381002516 -0500
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+++ linux-3.6.x86_64/fs/block_dev.c 2012-11-16 17:27:41.217005828 -0500
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@@ -127,7 +127,7 @@
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return -EINVAL;
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/* Prevent starting I/O or mapping the device */
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- down_write(&bdev->bd_block_size_semaphore);
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+ percpu_down_write(&bdev->bd_block_size_semaphore);
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/* Check that the block device is not memory mapped */
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mapping = bdev->bd_inode->i_mapping;
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@@ -135,7 +135,7 @@
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if (!prio_tree_empty(&mapping->i_mmap) ||
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!list_empty(&mapping->i_mmap_nonlinear)) {
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mutex_unlock(&mapping->i_mmap_mutex);
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- up_write(&bdev->bd_block_size_semaphore);
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+ percpu_up_write(&bdev->bd_block_size_semaphore);
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return -EBUSY;
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}
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mutex_unlock(&mapping->i_mmap_mutex);
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@@ -148,7 +148,7 @@
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kill_bdev(bdev);
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}
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- up_write(&bdev->bd_block_size_semaphore);
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+ percpu_up_write(&bdev->bd_block_size_semaphore);
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return 0;
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}
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@@ -460,6 +460,12 @@
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struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
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if (!ei)
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return NULL;
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+
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+ if (unlikely(percpu_init_rwsem(&ei->bdev.bd_block_size_semaphore))) {
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+ kmem_cache_free(bdev_cachep, ei);
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+ return NULL;
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+ }
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+
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return &ei->vfs_inode;
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}
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@@ -468,6 +474,8 @@
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struct inode *inode = container_of(head, struct inode, i_rcu);
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struct bdev_inode *bdi = BDEV_I(inode);
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+ percpu_free_rwsem(&bdi->bdev.bd_block_size_semaphore);
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+
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kmem_cache_free(bdev_cachep, bdi);
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}
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@@ -491,7 +499,6 @@
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inode_init_once(&ei->vfs_inode);
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/* Initialize mutex for freeze. */
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mutex_init(&bdev->bd_fsfreeze_mutex);
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||||||
|
- init_rwsem(&bdev->bd_block_size_semaphore);
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline void __bd_forget(struct inode *inode)
|
||||||
|
@@ -1593,11 +1600,11 @@
|
||||||
|
ssize_t ret;
|
||||||
|
struct block_device *bdev = I_BDEV(iocb->ki_filp->f_mapping->host);
|
||||||
|
|
||||||
|
- down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
|
||||||
|
|
||||||
|
- up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
@@ -1622,7 +1629,7 @@
|
||||||
|
|
||||||
|
blk_start_plug(&plug);
|
||||||
|
|
||||||
|
- down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
|
||||||
|
if (ret > 0 || ret == -EIOCBQUEUED) {
|
||||||
|
@@ -1633,7 +1640,7 @@
|
||||||
|
ret = err;
|
||||||
|
}
|
||||||
|
|
||||||
|
- up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
blk_finish_plug(&plug);
|
||||||
|
|
||||||
|
@@ -1646,11 +1653,11 @@
|
||||||
|
int ret;
|
||||||
|
struct block_device *bdev = I_BDEV(file->f_mapping->host);
|
||||||
|
|
||||||
|
- down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
ret = generic_file_mmap(file, vma);
|
||||||
|
|
||||||
|
- up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+ percpu_up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
Index: linux-3.6.x86_64/include/linux/fs.h
|
||||||
|
===================================================================
|
||||||
|
--- linux-3.6.x86_64.orig/include/linux/fs.h 2012-11-16 17:12:37.424002387 -0500
|
||||||
|
+++ linux-3.6.x86_64/include/linux/fs.h 2012-11-16 17:28:12.578901349 -0500
|
||||||
|
@@ -415,6 +415,7 @@
|
||||||
|
#include <linux/migrate_mode.h>
|
||||||
|
#include <linux/uidgid.h>
|
||||||
|
#include <linux/lockdep.h>
|
||||||
|
+#include <linux/percpu-rwsem.h>
|
||||||
|
|
||||||
|
#include <asm/byteorder.h>
|
||||||
|
|
||||||
|
@@ -725,7 +726,7 @@
|
||||||
|
/* Mutex for freeze */
|
||||||
|
struct mutex bd_fsfreeze_mutex;
|
||||||
|
/* A semaphore that prevents I/O while block size is being changed */
|
||||||
|
- struct rw_semaphore bd_block_size_semaphore;
|
||||||
|
+ struct percpu_rw_semaphore bd_block_size_semaphore;
|
||||||
|
};
|
||||||
|
|
||||||
|
/*
|
||||||
|
Index: linux-3.6.x86_64/include/linux/percpu-rwsem.h
|
||||||
|
===================================================================
|
||||||
|
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
|
||||||
|
+++ linux-3.6.x86_64/include/linux/percpu-rwsem.h 2012-11-16 17:12:57.354936574 -0500
|
||||||
|
@@ -0,0 +1,89 @@
|
||||||
|
+#ifndef _LINUX_PERCPU_RWSEM_H
|
||||||
|
+#define _LINUX_PERCPU_RWSEM_H
|
||||||
|
+
|
||||||
|
+#include <linux/mutex.h>
|
||||||
|
+#include <linux/percpu.h>
|
||||||
|
+#include <linux/rcupdate.h>
|
||||||
|
+#include <linux/delay.h>
|
||||||
|
+
|
||||||
|
+struct percpu_rw_semaphore {
|
||||||
|
+ unsigned __percpu *counters;
|
||||||
|
+ bool locked;
|
||||||
|
+ struct mutex mtx;
|
||||||
|
+};
|
||||||
|
+
|
||||||
|
+static inline void percpu_down_read(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ rcu_read_lock();
|
||||||
|
+ if (unlikely(p->locked)) {
|
||||||
|
+ rcu_read_unlock();
|
||||||
|
+ mutex_lock(&p->mtx);
|
||||||
|
+ this_cpu_inc(*p->counters);
|
||||||
|
+ mutex_unlock(&p->mtx);
|
||||||
|
+ return;
|
||||||
|
+ }
|
||||||
|
+ this_cpu_inc(*p->counters);
|
||||||
|
+ rcu_read_unlock();
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline void percpu_up_read(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ /*
|
||||||
|
+ * On X86, write operation in this_cpu_dec serves as a memory unlock
|
||||||
|
+ * barrier (i.e. memory accesses may be moved before the write, but
|
||||||
|
+ * no memory accesses are moved past the write).
|
||||||
|
+ * On other architectures this may not be the case, so we need smp_mb()
|
||||||
|
+ * there.
|
||||||
|
+ */
|
||||||
|
+#if defined(CONFIG_X86) && (!defined(CONFIG_X86_PPRO_FENCE) && !defined(CONFIG_X86_OOSTORE))
|
||||||
|
+ barrier();
|
||||||
|
+#else
|
||||||
|
+ smp_mb();
|
||||||
|
+#endif
|
||||||
|
+ this_cpu_dec(*p->counters);
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline unsigned __percpu_count(unsigned __percpu *counters)
|
||||||
|
+{
|
||||||
|
+ unsigned total = 0;
|
||||||
|
+ int cpu;
|
||||||
|
+
|
||||||
|
+ for_each_possible_cpu(cpu)
|
||||||
|
+ total += ACCESS_ONCE(*per_cpu_ptr(counters, cpu));
|
||||||
|
+
|
||||||
|
+ return total;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline void percpu_down_write(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ mutex_lock(&p->mtx);
|
||||||
|
+ p->locked = true;
|
||||||
|
+ synchronize_rcu();
|
||||||
|
+ while (__percpu_count(p->counters))
|
||||||
|
+ msleep(1);
|
||||||
|
+ smp_rmb(); /* paired with smp_mb() in percpu_sem_up_read() */
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline void percpu_up_write(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ p->locked = false;
|
||||||
|
+ mutex_unlock(&p->mtx);
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline int percpu_init_rwsem(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ p->counters = alloc_percpu(unsigned);
|
||||||
|
+ if (unlikely(!p->counters))
|
||||||
|
+ return -ENOMEM;
|
||||||
|
+ p->locked = false;
|
||||||
|
+ mutex_init(&p->mtx);
|
||||||
|
+ return 0;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static inline void percpu_free_rwsem(struct percpu_rw_semaphore *p)
|
||||||
|
+{
|
||||||
|
+ free_percpu(p->counters);
|
||||||
|
+ p->counters = NULL; /* catch use after free bugs */
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+#endif
|
|
@ -0,0 +1,74 @@
|
||||||
|
Lock splice_read and splice_write functions
|
||||||
|
|
||||||
|
commit 1a25b1c4ce189e3926f2981f3302352a930086db
|
||||||
|
Author: Mikulas Patocka <mpatocka@redhat.com>
|
||||||
|
Date: Mon Oct 15 17:20:17 2012 -0400
|
||||||
|
|
||||||
|
Lock splice_read and splice_write functions
|
||||||
|
|
||||||
|
Functions generic_file_splice_read and generic_file_splice_write access
|
||||||
|
the pagecache directly. For block devices these functions must be locked
|
||||||
|
so that block size is not changed while they are in progress.
|
||||||
|
|
||||||
|
This patch is an additional fix for commit b87570f5d349 ("Fix a crash
|
||||||
|
when block device is read and block size is changed at the same time")
|
||||||
|
that locked aio_read, aio_write and mmap against block size change.
|
||||||
|
|
||||||
|
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
|
||||||
|
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||||||
|
|
||||||
|
Index: linux-3.6.x86_64/fs/block_dev.c
|
||||||
|
===================================================================
|
||||||
|
--- linux-3.6.x86_64.orig/fs/block_dev.c 2012-11-16 17:12:57.352936580 -0500
|
||||||
|
+++ linux-3.6.x86_64/fs/block_dev.c 2012-11-16 17:13:11.908887989 -0500
|
||||||
|
@@ -1662,6 +1662,39 @@
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
+static ssize_t blkdev_splice_read(struct file *file, loff_t *ppos,
|
||||||
|
+ struct pipe_inode_info *pipe, size_t len,
|
||||||
|
+ unsigned int flags)
|
||||||
|
+{
|
||||||
|
+ ssize_t ret;
|
||||||
|
+ struct block_device *bdev = I_BDEV(file->f_mapping->host);
|
||||||
|
+
|
||||||
|
+ percpu_down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+
|
||||||
|
+ ret = generic_file_splice_read(file, ppos, pipe, len, flags);
|
||||||
|
+
|
||||||
|
+ percpu_up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+static ssize_t blkdev_splice_write(struct pipe_inode_info *pipe,
|
||||||
|
+ struct file *file, loff_t *ppos, size_t len,
|
||||||
|
+ unsigned int flags)
|
||||||
|
+{
|
||||||
|
+ ssize_t ret;
|
||||||
|
+ struct block_device *bdev = I_BDEV(file->f_mapping->host);
|
||||||
|
+
|
||||||
|
+ percpu_down_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+
|
||||||
|
+ ret = generic_file_splice_write(pipe, file, ppos, len, flags);
|
||||||
|
+
|
||||||
|
+ percpu_up_read(&bdev->bd_block_size_semaphore);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+
|
||||||
|
/*
|
||||||
|
* Try to release a page associated with block device when the system
|
||||||
|
* is under memory pressure.
|
||||||
|
@@ -1700,8 +1733,8 @@
|
||||||
|
#ifdef CONFIG_COMPAT
|
||||||
|
.compat_ioctl = compat_blkdev_ioctl,
|
||||||
|
#endif
|
||||||
|
- .splice_read = generic_file_splice_read,
|
||||||
|
- .splice_write = generic_file_splice_write,
|
||||||
|
+ .splice_read = blkdev_splice_read,
|
||||||
|
+ .splice_write = blkdev_splice_write,
|
||||||
|
};
|
||||||
|
|
||||||
|
int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg)
|
15
kernel.spec
15
kernel.spec
|
@ -54,7 +54,7 @@ Summary: The Linux kernel
|
||||||
# For non-released -rc kernels, this will be appended after the rcX and
|
# For non-released -rc kernels, this will be appended after the rcX and
|
||||||
# gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
|
# gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
|
||||||
#
|
#
|
||||||
%global baserelease 1
|
%global baserelease 2
|
||||||
%global fedora_build %{baserelease}
|
%global fedora_build %{baserelease}
|
||||||
|
|
||||||
# base_sublevel is the kernel version we're starting with and patching
|
# base_sublevel is the kernel version we're starting with and patching
|
||||||
|
@ -716,6 +716,11 @@ Patch22114: iwlwifi-remove-queue-empty-warn-3.6.patch
|
||||||
#rhbz 870562
|
#rhbz 870562
|
||||||
Patch22115: keyspan.patch
|
Patch22115: keyspan.patch
|
||||||
|
|
||||||
|
#rhbz 812129
|
||||||
|
Patch22120: block-fix-a-crash-when-block-device-is.patch
|
||||||
|
Patch22121: blockdev-turn-a-rw-semaphore-into-a-percpu-rw-sem.patch
|
||||||
|
Patch22122: fs-lock-splice_read-and-splice_write-functions.patch
|
||||||
|
|
||||||
# END OF PATCH DEFINITIONS
|
# END OF PATCH DEFINITIONS
|
||||||
|
|
||||||
%endif
|
%endif
|
||||||
|
@ -1349,6 +1354,11 @@ ApplyPatch iwlwifi-remove-queue-empty-warn-3.6.patch
|
||||||
#rhbz 870562
|
#rhbz 870562
|
||||||
ApplyPatch keyspan.patch
|
ApplyPatch keyspan.patch
|
||||||
|
|
||||||
|
#rhbz 812129
|
||||||
|
ApplyPatch block-fix-a-crash-when-block-device-is.patch
|
||||||
|
ApplyPatch blockdev-turn-a-rw-semaphore-into-a-percpu-rw-sem.patch
|
||||||
|
ApplyPatch fs-lock-splice_read-and-splice_write-functions.patch
|
||||||
|
|
||||||
# END OF PATCH APPLICATIONS
|
# END OF PATCH APPLICATIONS
|
||||||
|
|
||||||
%endif
|
%endif
|
||||||
|
@ -2049,6 +2059,9 @@ fi
|
||||||
# and build.
|
# and build.
|
||||||
|
|
||||||
%changelog
|
%changelog
|
||||||
|
* Mon Nov 19 2012 Josh Boyer <jwboyer@redhat.com>
|
||||||
|
- Apply patches from Jeff Moyer to fix direct-io oops (rhbz 812129)
|
||||||
|
|
||||||
* Sat Nov 17 2012 Justin M. Forbes <jforbes@linuxtx.org> - 3.6.7-1
|
* Sat Nov 17 2012 Justin M. Forbes <jforbes@linuxtx.org> - 3.6.7-1
|
||||||
- linux 3.6.7
|
- linux 3.6.7
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue