linux/drivers/block/floppy.c, branch v3.0.86

x86: Remove the ancient and deprecated disable_hlt() and enable_hlt() facility

2012-11-05T08:44:26Z

commit f6365201d8a21fb347260f89d6e9b3e718d63c70 upstream. The X86_32-only disable_hlt/enable_hlt mechanism was used by the 32-bit floppy driver. Its effect was to replace the use of the HLT instruction inside default_idle() with cpu_relax() - essentially it turned off the use of HLT. This workaround was commented in the code as: "disable hlt during certain critical i/o operations" "This halt magic was a workaround for ancient floppy DMA wreckage. It should be safe to remove." H. Peter Anvin additionally adds: "To the best of my knowledge, no-hlt only existed because of flaky power distributions on 386/486 systems which were sold to run DOS. Since DOS did no power management of any kind, including HLT, the power draw was fairly uniform; when exposed to the much hhigher noise levels you got when Linux used HLT caused some of these systems to fail. They were by far in the minority even back then." Alan Cox further says: "Also for the Cyrix 5510 which tended to go castors up if a HLT occurred during a DMA cycle and on a few other boxes HLT during DMA tended to go astray. Do we care ? I doubt it. The 5510 was pretty obscure, the 5520 fixed it, the 5530 is probably the oldest still in any kind of use." So, let's finally drop this. Signed-off-by: Len Brown Signed-off-by: Josh Boyer Signed-off-by: Andrew Morton Acked-by: "H. Peter Anvin" Acked-by: Alan Cox Cc: Stephen Hemminger Link: http://lkml.kernel.org/n/tip-3rhk9bzf0x9rljkv488tloib@git.kernel.org [ If anyone cares then alternative instruction patching could be used to replace HLT with a one-byte NOP instruction. Much simpler. ] Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

floppy: do put_disk on current dr if blk_init_queue fails

2012-11-05T08:44:25Z

commit 238ab78469c6ab7845b43d5061cd3c92331b2452 upstream. If blk_init_queue fails, we do not call put_disk on the current dr (dr is decremented first in the error handling loop). Reviewed-by: Ben Hutchings Signed-off-by: Herton Ronaldo Krzesinski Signed-off-by: Jiri Kosina Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

floppy: use del_timer_sync() in init cleanup

2011-10-03T18:40:36Z

commit 6c4867f6469964e34c5f4ee229a2a7f71a34c7ff upstream. When no floppy is found the module code can be released while a timer function is pending or about to be executed. CPU0 CPU1 floppy_init() timer_softirq() spin_lock_irq(&base->lock); detach_timer(); spin_unlock_irq(&base->lock); -> Interrupt del_timer(); return -ENODEV; module_cleanup(); <- EOI call_timer_fn(); OOPS Use del_timer_sync() to prevent this. Signed-off-by: Carsten Emde Signed-off-by: Thomas Gleixner Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6

2011-05-29T18:18:09Z

* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6: x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param x86 idle: deprecate "no-hlt" cmdline param x86 idle APM: deprecate CONFIG_APM_CPU_IDLE x86 idle floppy: deprecate disable_hlt() x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it x86 idle: clarify AMD erratum 400 workaround idle governor: Avoid lock acquisition to read pm_qos before entering idle cpuidle: menu: fixed wrapping timers at 4.294 seconds

x86 idle floppy: deprecate disable_hlt()

2011-05-29T07:39:15Z

Plan to remove floppy_disable_hlt in 2012, an ancient workaround with comments that it should be removed. This allows us to remove clutter and a run-time branch from the idle code. WARN_ONCE() on invocation until it is removed. cc: x86@kernel.org cc: stable@kernel.org # .39.x Signed-off-by: Len Brown

block: unexport DISK_EVENT_MEDIA_CHANGE for legacy/fringe drivers

2011-04-21T19:33:05Z

In-kernel disk event polling doesn't matter for legacy/fringe drivers and may lead to infinite event loop if ->check_events() implementation generates events on level condition instead of edge. Now that block layer supports suppressing exporting unlisted events, simply leaving disk->events cleared allows these drivers to keep the internal revalidation behavior intact while avoiding weird interactions with userland event handler. Signed-off-by: Tejun Heo Cc: Kay Sievers Signed-off-by: Jens Axboe

Merge branch 'for-2.6.39/stack-plug' into for-2.6.39/core

2011-03-10T07:58:35Z

Conflicts: block/blk-core.c block/blk-flush.c drivers/md/raid1.c drivers/md/raid10.c drivers/md/raid5.c fs/nilfs2/btnode.c fs/nilfs2/mdt.c Signed-off-by: Jens Axboe

block: remove per-queue plugging

2011-03-10T07:52:07Z

Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe

floppy,{ami|ata}flop: Convert to bdops->check_events()

2011-03-09T18:54:27Z

Convert the floppy drivers from ->media_changed() to ->check_events(). Both floppy and ataflop buffer media changed state bit and clear them on revalidation and will behave correctly with kernel event polling. I can't tell how amiflop clears its event and it's possible that it may generate spurious events when polled. Signed-off-by: Tejun Heo Cc: Jens Axboe Cc: Kay Sievers

Fix over-zealous flush_disk when changing device size.

2011-02-24T06:25:47Z

There are two cases when we call flush_disk. In one, the device has disappeared (check_disk_change) so any data will hold becomes irrelevant. In the oter, the device has changed size (check_disk_size_change) so data we hold may be irrelevant. In both cases it makes sense to discard any 'clean' buffers, so they will be read back from the device if needed. In the former case it makes sense to discard 'dirty' buffers as there will never be anywhere safe to write the data. In the second case it *does*not* make sense to discard dirty buffers as that will lead to file system corruption when you simply enlarge the containing devices. flush_disk calls __invalidate_devices. __invalidate_device calls both invalidate_inodes and invalidate_bdev. invalidate_inodes *does* discard I_DIRTY inodes and this does lead to fs corruption. invalidate_bev *does*not* discard dirty pages, but I don't really care about that at present. So this patch adds a flag to __invalidate_device (calling it __invalidate_device2) to indicate whether dirty buffers should be killed, and this is passed to invalidate_inodes which can choose to skip dirty inodes. flusk_disk then passes true from check_disk_change and false from check_disk_size_change. dm avoids tripping over this problem by calling i_size_write directly rathher than using check_disk_size_change. md does use check_disk_size_change and so is affected. This regression was introduced by commit 608aeef17a which causes check_disk_size_change to call flush_disk, so it is suitable for any kernel since 2.6.27. Cc: stable@kernel.org Acked-by: Jeff Moyer Cc: Andrew Patterson Cc: Jens Axboe Signed-off-by: NeilBrown