linux/drivers/ide/ide-io.c

900 lines
24 KiB

ide: Implement disk shock protection support (v4) On user request (through sysfs), the IDLE IMMEDIATE command with UNLOAD FEATURE as specified in ATA-7 is issued to the device and processing of the request queue is stopped thereafter until the specified timeout expires or user space asks to resume normal operation. This is supposed to prevent the heads of a hard drive from accidentally crashing onto the platter when a heavy shock is anticipated (like a falling laptop expected to hit the floor). Port resets are deferred whenever a device on that port is in the parked state. v3: Elias Oltmanns <eo@nebensachen.de> wrote: [...] > >> 1. Make sure that no negative value is being passed to > >> jiffies_to_msecs() in ide_park_show(). > >> 2. Drop the superfluous variable hwif in ide_special_rq(). > >> 3. Skip initialisation of task and tf in ide_special_rq() if we are not > >> handling a (un)park request. > > > > Well, #3 should have been done differently because we donn't want to > > check for REQ_(UN)?PARK_HEADS more often than is necessary. > > While preparing the backport to 2.6.27, it has just occurred to me that > we need to clear the IDE_DFLAG_PARKED flag in ide_disk_pre_reset() > because this flag must not be set after *any* sort of access to the > device. v4: Fix a memory leak due to a missing blk_put_request() in issue_park_cmd(). Additionally, we should plug the queue when enqueueing the unpark request because there is no guarantee that the park timeout has not expired by then. Even though the chance for that to happen is very slim, the request might end up hanging in the queue until the next I/O operation is queued up. While at it, clean up the code a little: - make issue_park_cmd() a function of type void since nobody cares for the return value anyway; - use blk_start_queueing() instead of __blk_run_queue() since we don't have to worry about recursion; - remove a superfluous pointer deference in task_no_data_intr(). Signed-off-by: Elias Oltmanns <eo@nebensachen.de> Cc: Jeff Garzik <jeff@garzik.org>, Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Tejun Heo <htejun@gmail.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-10-13 21:39:50 +02:00
ide-io: set REQ_FAILED when drive is dead Currently it's possible to ide-cd to set an incorrect blocksize by reading garbage if the drive is dead: ide_cd_probe() -> cdrom_read_toc() -> cdrom_read_capacity() -> cdrom_queue_packet_command() -> ide_do_drive_cmd() -> ide_do_request() -> start_request() on start_request(): /* bail early if we've exceeded max_failures */ if (drive->max_failures && (drive->failures > drive->max_failures)) { goto kill_rq; } (...) kill_rq: ide_kill_rq(drive, rq); return ide_stopped; ide_kill_rq() and the next calls won't set REQ_FAILED on rq->cmd_flags and thus cdrom_queue_packet_command() won't return an error. then: stat = cdrom_queue_packet_command(drive, &req); if (stat == 0) { *capacity = 1 + be32_to_cpu(capbuf.lba); *sectors_per_frame = be32_to_cpu(capbuf.blocklen) >> SECTOR_BITS; } cdrom_read_capacity() ends believing capbuf is valid but in fact it's just uninitialized data. back to cdrom_read_toc(): /* Try to get the total cdrom capacity and sector size. */ stat = cdrom_read_capacity(drive, &toc->capacity, &sectors_per_frame, sense); if (stat) toc->capacity = 0x1fffff; set_capacity(info->disk, toc->capacity * sectors_per_frame); /* Save a private copy of te TOC capacity for error handling */ drive->probed_capacity = toc->capacity * sectors_per_frame; blk_queue_hardsect_size(drive->queue, sectors_per_frame << SECTOR_BITS); that will set drive->queue->hardsect_size to be the random value. hardsect_size is used to calculate inode->i_blkbits. later on, on a read path: void create_empty_buffers(struct page *page, unsigned long blocksize, unsigned long b_state) { struct buffer_head *bh, *head, *tail; head = alloc_page_buffers(page, blocksize, 1); bh = head; do { bh->b_state |= b_state; tail = bh; bh = bh->b_this_page; } while (bh); tail->b_this_page = head; alloc_page_buffers() will return NULL if blocksize > 4096. blocksize is calculed based on inode->i_blkbits. that will trigger a null dereference on create_empty_buffers(). Signed-off-by: Aristeu Rozanski <arozansk@redhat.com> Cc: Borislav Petkov <bbpetkov@yahoo.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-01-25 22:17:04 +01:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 07:00:42 +09:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide: Implement disk shock protection support (v4) On user request (through sysfs), the IDLE IMMEDIATE command with UNLOAD FEATURE as specified in ATA-7 is issued to the device and processing of the request queue is stopped thereafter until the specified timeout expires or user space asks to resume normal operation. This is supposed to prevent the heads of a hard drive from accidentally crashing onto the platter when a heavy shock is anticipated (like a falling laptop expected to hit the floor). Port resets are deferred whenever a device on that port is in the parked state. v3: Elias Oltmanns <eo@nebensachen.de> wrote: [...] > >> 1. Make sure that no negative value is being passed to > >> jiffies_to_msecs() in ide_park_show(). > >> 2. Drop the superfluous variable hwif in ide_special_rq(). > >> 3. Skip initialisation of task and tf in ide_special_rq() if we are not > >> handling a (un)park request. > > > > Well, #3 should have been done differently because we donn't want to > > check for REQ_(UN)?PARK_HEADS more often than is necessary. > > While preparing the backport to 2.6.27, it has just occurred to me that > we need to clear the IDE_DFLAG_PARKED flag in ide_disk_pre_reset() > because this flag must not be set after *any* sort of access to the > device. v4: Fix a memory leak due to a missing blk_put_request() in issue_park_cmd(). Additionally, we should plug the queue when enqueueing the unpark request because there is no guarantee that the park timeout has not expired by then. Even though the chance for that to happen is very slim, the request might end up hanging in the queue until the next I/O operation is queued up. While at it, clean up the code a little: - make issue_park_cmd() a function of type void since nobody cares for the return value anyway; - use blk_start_queueing() instead of __blk_run_queue() since we don't have to worry about recursion; - remove a superfluous pointer deference in task_no_data_intr(). Signed-off-by: Elias Oltmanns <eo@nebensachen.de> Cc: Jeff Garzik <jeff@garzik.org>, Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Tejun Heo <htejun@gmail.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-10-13 21:39:50 +02:00
block: implement and enforce request peek/start/fetch Till now block layer allowed two separate modes of request execution. A request is always acquired from the request queue via elv_next_request(). After that, drivers are free to either dequeue it or process it without dequeueing. Dequeue allows elv_next_request() to return the next request so that multiple requests can be in flight. Executing requests without dequeueing has its merits mostly in allowing drivers for simpler devices which can't do sg to deal with segments only without considering request boundary. However, the benefit this brings is dubious and declining while the cost of the API ambiguity is increasing. Segment based drivers are usually for very old or limited devices and as converting to dequeueing model isn't difficult, it doesn't justify the API overhead it puts on block layer and its more modern users. Previous patches converted all block low level drivers to dequeueing model. This patch completes the API transition by... * renaming elv_next_request() to blk_peek_request() * renaming blkdev_dequeue_request() to blk_start_request() * adding blk_fetch_request() which is combination of peek and start * disallowing completion of queued (not started) requests * applying new API to all LLDs Renamings are for consistency and to break out of tree code so that it's apparent that out of tree drivers need updating. [ Impact: block request issue API cleanup, no functional change ] Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Mike Miller <mike.miller@hp.com> Cc: unsik Kim <donari75@gmail.com> Cc: Paul Clements <paul.clements@steeleye.com> Cc: Tim Waugh <tim@cyberelk.net> Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Cc: David S. Miller <davem@davemloft.net> Cc: Laurent Vivier <Laurent@lvivier.info> Cc: Jeff Garzik <jgarzik@pobox.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Borislav Petkov <petkovbb@googlemail.com> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Alex Dubov <oakad@yahoo.com> Cc: Pierre Ossman <drzeus@drzeus.cx> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Markus Lidel <Markus.Lidel@shadowconnect.com> Cc: Stefan Weinhuber <wein@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Pete Zaitcev <zaitcev@redhat.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-08 11:54:16 +09:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
ide: don't execute the next queued command from the hard-IRQ context (v2) * Tell the block layer that we are not done handling requests by using blk_plug_device() in ide_do_request() (request handling function) and ide_timer_expiry() (timeout handler) if the queue is not empty. * Remove optimization which directly calls ide_do_request() for the next queued command from the ide_intr() (IRQ handler) and ide_timer_expiry(). * Remove no longer needed IRQ masking from ide_do_request() - in case of IDE ports needing serialization disable_irq_nosync()/enable_irq() was used for the (possibly shared) IRQ of the other IDE port. * Put the misplaced comment in the right place in ide_do_request(). * Drop no longer needed 'int masked_irq' argument from ide_do_request(). * Merge ide_do_request() into do_ide_request(). * Remove no longer needed IDE_NO_IRQ define. While at it: * Don't use HWGROUP() macro in do_ide_request(). * Use __func__ in ide_intr(). This patch reduces IRQ hadling latency for IDE and improves the system-wide handling of shared IRQs (which should result in more timeout resistant and stable IDE systems). It also makes it possible to do some further changes later (i.e. replace some busy-waiting delays with sleeping equivalents). v2: Changes per review from Elias Oltmanns: - fix wrong goto statement in 'if (startstop == ide_stopped)' block - use spin_unlock_irq() - don't use obsolete HWIF() macro Cc: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-02 16:12:48 +01:00
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 14:55:46 +01:00