Merge 'block-dev' branch. I was going to just mark everything here for stable and leave it to the 3.8 merge window, but having decided on doing another -rc, I migth as well merge it now. This removes the bd_block_size_semaphore semaphore that was added in this release to fix a race condition between block size changes and block IO, and replaces it with atomicity guaratees in fs/buffer.c instead, along with simplifying fs/block-dev.c. This removes more lines than it adds, makes the code generally simpler, and avoids the latency/rt issues that the block size semaphore introduced for mount. I'm not happy with the timing, but it wouldn't be much better doing this during the merge window and then having some delayed back-port of it into stable. * block-dev: blkdev_max_block: make private to fs/buffer.c direct-io: don't read inode->i_blkbits multiple times blockdev: remove bd_block_size_semaphore again fs/buffer.c: make block-size be per-page and protected by the page lock
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| @@ -462,8 +462,6 @@ struct block_device { · 461 unmodified lines | ||
| 462 | 462 | int bd_fsfreeze_count; |
| 463 | 463 | /* Mutex for freeze */ |
| 464 | 464 | struct mutex bd_fsfreeze_mutex; |
| 465 | − /* A semaphore that prevents I/O while block size is being changed */ | |
| 466 | − struct percpu_rw_semaphore bd_block_size_semaphore; | |
| 467 | 465 | }; |
| 468 | 466 | |
| 469 | 467 | /* |
| @@ -2049,7 +2047,6 @@ extern void unregister_blkdev(unsigned int, const char *); · 1579 unmodified lines | ||
| 2049 | 2047 | extern struct block_device *bdget(dev_t); |
| 2050 | 2048 | extern struct block_device *bdgrab(struct block_device *bdev); |
| 2051 | 2049 | extern void bd_set_size(struct block_device *, loff_t size); |
| 2052 | −extern sector_t blkdev_max_block(struct block_device *bdev); | |
| 2053 | 2050 | extern void bd_forget(struct inode *inode); |
| 2054 | 2051 | extern void bdput(struct block_device *); |
| 2055 | 2052 | extern void invalidate_bdev(struct block_device *); |
| @@ -2379,8 +2376,6 @@ extern int generic_segment_checks(const struct iovec *iov, · 323 unmodified lines | ||
| 2379 | 2376 | unsigned long *nr_segs, size_t *count, int access_flags); |
| 2380 | 2377 | |
| 2381 | 2378 | /* fs/block_dev.c */ |
| 2382 | −extern ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov, | |
| 2383 | − unsigned long nr_segs, loff_t pos); | |
| 2384 | 2379 | extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, |
| 2385 | 2380 | unsigned long nr_segs, loff_t pos); |
| 2386 | 2381 | extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end, |