We have enough vtables in the kernel as it is, we don't need
this one to create even more artificial separation of concerns.

As is proved by the Makefile:

obj-$(CONFIG_MMC_BLOCK)         += mmc_block.o
mmc_block-objs                  := block.o queue.o

block.c and queue.c are baked into the same mmc_block.o object.
So why would one of these objects access a function in the
other object by dereferencing a pointer?

Create a new block.h header file for the single shared function
from block to queue and remove the function pointer and just
call the queue request function.

Apart from making the code more readable, this also makes link
optimizations possible and probably speeds up the call as well.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

We call mmc_req_is_special() after having processed a request, but
it could be freed after that. Check that ahead of time, and use
the cached value.

Reported-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Fixes: c2df40dfb8c0 ("drivers: use req op accessor")

Signed-off-by: Jens Axboe <axboe@fb.com>

Commit 288dab8a35a0 ("block: add a separate operation type for secure
erase") split REQ_OP_SECURE_ERASE from REQ_OP_DISCARD without considering
all the places REQ_OP_DISCARD was being used to mean either. Fix those.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 288dab8a35a0 ("block: add a separate operation type for secure erase")
Signed-off-by: Jens Axboe <axboe@fb.com>

Instead of overloading the discard support with the REQ_SECURE flag.
Use the opportunity to rename the queue flag as well, and remove the
dead checks for this flag in the RAID 1 and RAID 10 drivers that don't
claim support for secure erase.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[hch: split from a larger patch by Dan]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

Some drivers use it now, others just set the limits field manually.
But in preparation for splitting this into a hard and soft limit,
ensure that they all call the proper function for setting the hw
limit for discards.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

On systems with CONFIG_PREEMPT=n, under certain circumstances, mmcqd
can continuously process requests for several seconds without blocking,
triggering the soft lockup watchdog.  For example, this can happen if
mmcqd runs on the CPU which services the controller's interrupt, and
a process on a different CPU continuously writes to the MMC block
device.

 NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [mmcqd/0:664]
 CPU: 0 PID: 664 Comm: mmcqd/0 Not tainted 4.1.0-rc7+ #4
 PC is at _raw_spin_unlock_irqrestore+0x24/0x28
 LR is at mmc_start_request+0x104/0x134
 ...
 [<805112a8>] (_raw_spin_unlock_irqrestore) from [<803db664>] (mmc_start_request+0x104/0x134)
 [<803db664>] (mmc_start_request) from [<803dc008>] (mmc_start_req+0x274/0x394)
 [<803dc008>] (mmc_start_req) from [<803eb2c4>] (mmc_blk_issue_rw_rq+0xd0/0xb98)
 [<803eb2c4>] (mmc_blk_issue_rw_rq) from [<803ebe8c>] (mmc_blk_issue_rq+0x100/0x470)
 [<803ebe8c>] (mmc_blk_issue_rq) from [<803ecab8>] (mmc_queue_thread+0xd0/0x170)
 [<803ecab8>] (mmc_queue_thread) from [<8003fd14>] (kthread+0xe0/0xfc)
 [<8003fd14>] (kthread) from [<8000f768>] (ret_from_fork+0x14/0x2c)

Fix it by adding a cond_resched() in the request handling loop so that
other processes get a chance to run.

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

During kernel boot, it will try to read some logical sectors
of each block device node for the possible partition table.

But since RPMB partition is special and can not be accessed
by normal eMMC read / write CMDs, it will cause below error
messages during kernel boot:
...
 mmc0: Got data interrupt 0x00000002 even though no data operation was in progress.
 mmcblk0rpmb: error -110 transferring data, sector 0, nr 32, cmd response 0x900, card status 0xb00
 mmcblk0rpmb: retrying using single block read
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 mmcblk0rpmb: timed out sending r/w cmd command, card status 0x400900
 end_request: I/O error, dev mmcblk0rpmb, sector 0
 Buffer I/O error on device mmcblk0rpmb, logical block 0
 end_request: I/O error, dev mmcblk0rpmb, sector 8
 Buffer I/O error on device mmcblk0rpmb, logical block 1
 end_request: I/O error, dev mmcblk0rpmb, sector 16
 Buffer I/O error on device mmcblk0rpmb, logical block 2
 end_request: I/O error, dev mmcblk0rpmb, sector 24
 Buffer I/O error on device mmcblk0rpmb, logical block 3
...

This patch will discard the access request in eMMC queue if
it is RPMB partition access request. By this way, it avoids
trigger above error messages.

Fixes: 090d25fe224c ("mmc: core: Expose access to RPMB partition")
Signed-off-by: Yunpeng Gao <yunpeng.gao@intel.com>
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Tested-by: Michael Shigorin <mike@altlinux.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>