There's a chance that the IDA allocated in mmc_alloc_host() is not freed
for some time because it's freed as part of a class' release function
(see mmc_host_classdev_release() where the IDA is freed). If another
thread is holding a reference to the class, then only once all balancing
device_put() calls (in turn calling kobject_put()) have been made will
the IDA be released and usable again.
Normally this isn't a problem because the kobject is released before
anything else that may want to use the same number tries to again, but
with CONFIG_DEBUG_KOBJECT_RELEASE=y and OF aliases it becomes pretty
easy to try to allocate an alias from the IDA twice while the first time
it was allocated is still pending a call to ida_simple_remove(). It's
also possible to trigger it by using CONFIG_DEBUG_KOBJECT_RELEASE and
probe defering a driver at boot that calls mmc_alloc_host() before
trying to get resources that may defer likes clks or regulators.
Instead of allocating from the IDA in this scenario, let's just skip it
if we know this is an OF alias. The number is already "claimed" and
devices that aren't using OF aliases won't try to use the claimed
numbers anyway (see mmc_first_nonreserved_index()). This should avoid
any issues with mmc_alloc_host() returning failures from the
ida_simple_get() in the case that we're using an OF alias.
Cc: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Cc: Sujit Kautkar <sujitka@chromium.org>
Reported-by: Zubin Mithra <zsm@chromium.org>
Fixes: fa2d0aa969 ("mmc: core: Allow setting slot index via device tree alias")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20210623075002.1746924-3-swboyd@chromium.org
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Ulf reported the following KASAN splat after adding some manual hacks
into mmc-utils[1].
DEBUG: mmc_blk_open: Let's sleep for 10s..
mmc1: card 0007 removed
BUG: KASAN: use-after-free in mmc_blk_get+0x58/0xb8
Read of size 4 at addr ffff00000a394a28 by task mmc/180
CPU: 2 PID: 180 Comm: mmc Not tainted 5.10.0-rc4-00069-gcc758c8c7127-dirty #5
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
Call trace:
dump_backtrace+0x0/0x2b4
show_stack+0x18/0x6c
dump_stack+0xfc/0x168
print_address_description.constprop.0+0x6c/0x488
kasan_report+0x118/0x210
__asan_load4+0x94/0xd0
mmc_blk_get+0x58/0xb8
mmc_blk_open+0x7c/0xdc
__blkdev_get+0x3b4/0x964
blkdev_get+0x64/0x100
blkdev_open+0xe8/0x104
do_dentry_open+0x234/0x61c
vfs_open+0x54/0x64
path_openat+0xe04/0x1584
do_filp_open+0xe8/0x1e4
do_sys_openat2+0x120/0x230
__arm64_sys_openat+0xf0/0x15c
el0_svc_common.constprop.0+0xac/0x234
do_el0_svc+0x84/0xa0
el0_sync_handler+0x264/0x270
el0_sync+0x174/0x180
Allocated by task 33:
stack_trace_save+0x9c/0xdc
kasan_save_stack+0x28/0x60
__kasan_kmalloc.constprop.0+0xc8/0xf0
kasan_kmalloc+0x10/0x20
mmc_blk_alloc_req+0x94/0x4b0
mmc_blk_probe+0x2d4/0xaa4
mmc_bus_probe+0x34/0x4c
really_probe+0x148/0x6e0
driver_probe_device+0x78/0xec
__device_attach_driver+0x108/0x16c
bus_for_each_drv+0xf4/0x15c
__device_attach+0x168/0x240
device_initial_probe+0x14/0x20
bus_probe_device+0xec/0x100
device_add+0x55c/0xaf0
mmc_add_card+0x288/0x380
mmc_attach_sd+0x18c/0x22c
mmc_rescan+0x444/0x4f0
process_one_work+0x3b8/0x650
worker_thread+0xa0/0x724
kthread+0x218/0x220
ret_from_fork+0x10/0x38
Freed by task 33:
stack_trace_save+0x9c/0xdc
kasan_save_stack+0x28/0x60
kasan_set_track+0x28/0x40
kasan_set_free_info+0x24/0x4c
__kasan_slab_free+0x100/0x180
kasan_slab_free+0x14/0x20
kfree+0xb8/0x46c
mmc_blk_put+0xe4/0x11c
mmc_blk_remove_req.part.0+0x6c/0xe4
mmc_blk_remove+0x368/0x370
mmc_bus_remove+0x34/0x50
__device_release_driver+0x228/0x31c
device_release_driver+0x2c/0x44
bus_remove_device+0x1e4/0x200
device_del+0x2b0/0x770
mmc_remove_card+0xf0/0x150
mmc_sd_detect+0x9c/0x150
mmc_rescan+0x110/0x4f0
process_one_work+0x3b8/0x650
worker_thread+0xa0/0x724
kthread+0x218/0x220
ret_from_fork+0x10/0x38
The buggy address belongs to the object at ffff00000a394800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 552 bytes inside of
1024-byte region [ffff00000a394800, ffff00000a394c00)
The buggy address belongs to the page:
page:00000000ff84ed53 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8a390
head:00000000ff84ed53 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x3fffc0000010200(slab|head)
raw: 03fffc0000010200 dead000000000100 dead000000000122 ffff000009f03800
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff00000a394900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff00000a394980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff00000a394a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff00000a394a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff00000a394b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
Looking closer at the problem, it looks like a classic dangling pointer
bug. The 'struct mmc_blk_data' that is used after being freed in
mmc_blk_put() is stashed away in 'md->disk->private_data' via
mmc_blk_alloc_req() but used in mmc_blk_get() because the 'usage' count
isn't properly aligned with the lifetime of the pointer. You'd expect
the 'usage' member to be in sync with the kfree(), and it mostly is,
except that mmc_blk_get() needs to dereference the potentially freed
memory storage for the 'struct mmc_blk_data' stashed away in the
private_data member to look at 'usage' before it actually figures out if
it wants to consider it a valid pointer or not. That's not going to work
if the freed memory has been overwritten by something else after the
free, and KASAN rightly complains here.
To fix the immediate problem, let's set the private_data member to NULL
in mmc_blk_put() so that mmc_blk_get() can consider the object "on the
way out" if the pointer is NULL and not even try to look at 'usage' if
the object isn't going to be around much longer. With that set to NULL
on the last mmc_blk_put(), optimize the get path further and use a kref
underneath the 'open_lock' mutex to only up the reference count if it's
non-zero, i.e. alive, and otherwise make mmc_blk_get() return NULL,
without actually testing the reference count if we're in the process of
removing the object from the system.
Finally, tighten the locking region on the put side to only be around
the parts that are removing the 'mmc_blk_data' from the system and
publishing that fact to the gendisk and then drop the lock as soon as we
can to avoid holding the lock around code that doesn't need it. This
fixes the KASAN issue.
Cc: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Cc: Sujit Kautkar <sujitka@chromium.org>
Cc: Zubin Mithra <zsm@chromium.org>
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/linux-mmc/CAPDyKFryT63Jc7+DXWSpAC19qpZRqFr1orxwYGMuSqx247O8cQ@mail.gmail.com/ [1]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20210623075002.1746924-2-swboyd@chromium.org
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Merge tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-block
Pull more block updates from Jens Axboe:
"A combination of changes that ended up depending on both the driver
and core branch (and/or the IDE removal), and a few late arriving
fixes. In detail:
- Fix io ticks wrap-around issue (Chunguang)
- nvme-tcp sock locking fix (Maurizio)
- s390-dasd fixes (Kees, Christoph)
- blk_execute_rq polling support (Keith)
- blk-cgroup RCU iteration fix (Yu)
- nbd backend ID addition (Prasanna)
- Partition deletion fix (Yufen)
- Use blk_mq_alloc_disk for mmc, mtip32xx, ubd (Christoph)
- Removal of now dead block request types due to IDE removal
(Christoph)
- Loop probing and control device cleanups (Christoph)
- Device uevent fix (Christoph)
- Misc cleanups/fixes (Tetsuo, Christoph)"
* tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-block: (34 commits)
blk-cgroup: prevent rcu_sched detected stalls warnings while iterating blkgs
block: fix the problem of io_ticks becoming smaller
nvme-tcp: can't set sk_user_data without write_lock
loop: remove unused variable in loop_set_status()
block: remove the bdgrab in blk_drop_partitions
block: grab a device refcount in disk_uevent
s390/dasd: Avoid field over-reading memcpy()
dasd: unexport dasd_set_target_state
block: check disk exist before trying to add partition
ubd: remove dead code in ubd_setup_common
nvme: use return value from blk_execute_rq()
block: return errors from blk_execute_rq()
nvme: use blk_execute_rq() for passthrough commands
block: support polling through blk_execute_rq
block: remove REQ_OP_SCSI_{IN,OUT}
block: mark blk_mq_init_queue_data static
loop: rewrite loop_exit using idr_for_each_entry
loop: split loop_lookup
loop: don't allow deleting an unspecified loop device
loop: move loop_ctl_mutex locking into loop_add
...
Here is the big set of tty and serial driver patches for 5.14-rc1.
A bit more than normal, but nothing major, lots of cleanups. Highlights
are:
- lots of tty api cleanups and mxser driver cleanups from Jiri
- build warning fixes
- various serial driver updates
- coding style cleanups
- various tty driver minor fixes and updates
- removal of broken and disable r3964 line discipline (finally!)
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty / serial updates from Greg KH:
"Here is the big set of tty and serial driver patches for 5.14-rc1.
A bit more than normal, but nothing major, lots of cleanups.
Highlights are:
- lots of tty api cleanups and mxser driver cleanups from Jiri
- build warning fixes
- various serial driver updates
- coding style cleanups
- various tty driver minor fixes and updates
- removal of broken and disable r3964 line discipline (finally!)
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (227 commits)
serial: mvebu-uart: remove unused member nb from struct mvebu_uart
arm64: dts: marvell: armada-37xx: Fix reg for standard variant of UART
dt-bindings: mvebu-uart: fix documentation
serial: mvebu-uart: correctly calculate minimal possible baudrate
serial: mvebu-uart: do not allow changing baudrate when uartclk is not available
serial: mvebu-uart: fix calculation of clock divisor
tty: make linux/tty_flip.h self-contained
serial: Prefer unsigned int to bare use of unsigned
serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs
serial: qcom_geni_serial: use DT aliases according to DT bindings
Revert "tty: serial: Add UART driver for Cortina-Access platform"
tty: serial: Add UART driver for Cortina-Access platform
MAINTAINERS: add me back as mxser maintainer
mxser: Documentation, fix typos
mxser: Documentation, make the docs up-to-date
mxser: Documentation, remove traces of callout device
mxser: introduce mxser_16550A_or_MUST helper
mxser: rename flags to old_speed in mxser_set_serial_info
mxser: use port variable in mxser_set_serial_info
mxser: access info->MCR under info->slock
...
Fix a let hunk from the blk_mq_alloc_disk conversion.
Fixes: 281ea6a5bfdc ("mmc: switch to blk_mq_alloc_disk")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210621080144.3655131-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use the blk_mq_alloc_disk to allocate the request_queue and gendisk
together.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210616053934.880951-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The gendisk already acquires a reference to the queue when add_disk
is called, which dropped on put_disk. So remove the superflous
extra refcounting.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210616053934.880951-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It might be that something goes wrong during tuning so the MMC core will
immediately trigger a retune. In our case it was:
- we sent a tuning block
- there was an error so we need to send an abort cmd to the eMMC
- the abort cmd had a CRC error
- retune was set by the MMC core
This lead to a vicious circle causing a performance regression of 75%.
So, clear retuning flags before we enable retuning to start with a known
cleared state.
Reported-by Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: bd11e8bd03 ("mmc: core: Flag re-tuning is needed on CRC errors")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210624151616.38770-2-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
'mmc_abort_tuning()' made me think tuning gets completely aborted.
However, it sends only a STOP cmd to cancel the current tuning cmd.
Tuning process may still continue after that. So, rename the function to
'mmc_send_abort_tuning()' to better reflect all this.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20210608180620.40059-1-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
While initializing an UHS-I SD card, the mmc core first tries to switch to
1.8V I/O voltage, before it continues to change the settings for the bus
speed mode.
However, the current behaviour in the mmc core is inconsistent and doesn't
conform to the SD spec. More precisely, an SD card that supports UHS-I must
set both the SD_OCR_CCS bit and the SD_OCR_S18R bit in the OCR register
response. When switching to 1.8V I/O the mmc core correctly checks both of
the bits, but only the SD_OCR_S18R bit when changing the settings for bus
speed mode.
Rather than actually fixing the code to confirm to the SD spec, let's
deliberately deviate from it by requiring only the SD_OCR_S18R bit for both
parts. This enables us to support UHS-I for SDSC cards (outside spec),
which is actually being supported by some existing SDSC cards. Moreover,
this fixes the inconsistent behaviour.
Signed-off-by: Christian Loehle <cloehle@hyperstone.com>
Link: https://lore.kernel.org/r/CWXP265MB26803AE79E0AD5ED083BF2A6C4529@CWXP265MB2680.GBRP265.PROD.OUTLOOK.COM
Cc: stable@vger.kernel.org
[Ulf: Rewrote commit message and comments to clarify the changes]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
use pm_runtime_resume_and_get() to replace pm_runtime_get_sync and
pm_runtime_put_noidle. this change is just to simplify the code, no
actual functional changes
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1621513304-27824-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
On some boards the data strobe line isn't wired up, rendering HS400
support broken, even if both the controller and the eMMC claim to
support it. Allow to disable HS400 mode via DT.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Link: https://lore.kernel.org/r/20210510190400.105162-3-l.stach@pengutronix.de
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In SD spec v6.x the SD function extension registers for performance
enhancements were introduced. As a part of this an optional internal cache
on the SD card, can be used to improve performance.
The let the SD card use the cache, the host needs to enable it and manage
flushing of the cache, so let's add support for this.
Note that for an SD card supporting the cache it's mandatory for it, to
also support the poweroff notification feature. According to the SD spec,
if the cache has been enabled and a poweroff notification is sent to the
card, that implicitly also means that the card should flush its internal
cache. Therefore, dealing with cache flushing for REQ_OP_FLUSH block
requests is sufficient.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210511101359.83521-1-ulf.hansson@linaro.org
To prepare to add internal cache management for SD cards, let's start by
moving the eMMC specific code into a new ->flush_cache() bus_ops callback.
In this way, it becomes straight forward to add the SD specific parts,
as subsequent changes are about to show.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210506145829.198823-2-ulf.hansson@linaro.org
According to the eMMC Spec:
"When command queuing is enabled (CMDQ Mode En bit in CMDQ_MODE_EN
field is set to ‘1’) class 11 commands are the only method through
which data transfer tasks can be issued. Existing data transfer
commands, namely CMD18/CMD17 and CMD25/CMD24, are not supported when
command queuing is enabled."
which means if CMDQ is enabled, the FFU commands will not be supported.
To fix this issue, just simply disable CMDQ on the ioctl path, and
re-enable CMDQ once ioctl request is completed.
Tested-by: Michael Brunner <Michael.Brunner@kontron.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 1e8e55b670 (mmc: block: Add CQE support)
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210504203209.361597-1-huobean@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Rather than only deselecting the SD card via a CMD7, before we cut power to
it at system suspend, at runtime suspend or at shutdown, let's add support
for a graceful power off sequence via enabling the SD Power Off
Notification feature.
Note that, the Power Off Notification feature was added in the SD spec
v4.x, which is several years ago. However, it's still a bit unclear how
often the SD card vendors decides to implement support for it. To validate
these changes a Sandisk Extreme PRO A2 64GB has been used, which seems to
work nicely.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://lore.kernel.org/r/20210504161222.101536-12-ulf.hansson@linaro.org
In SD spec v6.x the SD function extension registers for performance
enhancements were introduced. These registers let the SD card announce
supports for various performance related features, like "self-maintenance",
"cache" and "command queuing".
Let's extend the parsing of SD function extension registers and store the
information in the struct mmc_card. This prepares for subsequent changes to
implement the complete support for new the performance enhancement
features.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://lore.kernel.org/r/20210504161222.101536-11-ulf.hansson@linaro.org
In the SD spec v4.0 the CMD48/49 and CMD58/59 were introduced as optional
commands. In the SD spec v4.1 the SD function extension registers were
introduced, which requires support for CMD48/49/58/59 to be read/written
from/to.
Moreover, a specific function extension register were added to let the card
announce support for optional features in regards to power management. The
features that were added are "Power Off Notification", "Power Down Mode"
and "Power Sustenance".
As a first step to support this, let's read and parse the register for
power management during the SD card initialization and store the
information about the supported features in the struct mmc_card. In this
way, we prepare for subsequent changes to implement the complete support
for the new features.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-10-ulf.hansson@linaro.org
In SD spec v4.x the support for CMD48/49 and CMD58/59 were introduced as
optional features. To let the card announce whether it supports the
commands, the SCR register has been extended with corresponding support
bits. Let's parse and store this information for later use.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-9-ulf.hansson@linaro.org
The SD_SWITCH (CMD6) is an ADTC type of command with an R1 response, which
can be sent by using the mmc_send_adtc_data(). Let's do that and drop the
open coding in mmc_sd_switch().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-8-ulf.hansson@linaro.org
The function mmc_send_cxd_data() sends a data read command of ADTC type and
prepares to receive an R1 response. To make it even more re-usable, let's
extend it with another in-parameter for the command argument. While at it,
let's also rename the function to mmc_send_adtc_data() as it better
describes its purpose.
Note that, this change doesn't add any new users of the function. Instead
that is done from subsequent changes.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-7-ulf.hansson@linaro.org
After the eMMC sleep command (CMD5) has been sent, the card start signals
busy on the DAT0 line, which can be monitored to understand when it's
allowed to proceed to power off the VCC regulator.
When MMC_CAP_WAIT_WHILE_BUSY isn't supported by the host the DAT0 line
isn't being monitored for busy completion, but instead we are waiting a
fixed period of time. The time corresponds to the sleep timeout that is
specified in the EXT_CSD register of the eMMC card. This is many cases
suboptimal, as the timeout corresponds to the worst case scenario.
To improve the situation add support for HW busy polling through the
->card_busy() host ops, when the host supports this.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-6-ulf.hansson@linaro.org
Via __mmc_poll_for_busy() we end up polling with the ->card_busy() host ops
or by sending the CMD13. To allow polling of different types, which is
needed to support a few new SD card features, let's rework the code around
__mmc_poll_for_busy() to make it more generic.
More precisely, let __mmc_poll_for_busy() take a pointer to a callback
function as in-parameter, which it calls to poll for busy state completion.
Additionally, let's share __mmc_poll_for_busy() to allow it to be re-used
outside of mmc_ops.c. Subsequent changes will make use of it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-5-ulf.hansson@linaro.org
To make the code a bit more understandable, let's move the check about
whether polling is allowed or not, out to the caller instead. In this way,
we can also drop the send_status in-parameter, so let's do that.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-4-ulf.hansson@linaro.org
In mmc_send_hpi_cmd() the host->max_busy_timeout is being validated towards
the timeout for the eMMC HPI command, as to decide whether an R1 or R1B
response should be used.
Although, it has turned out the some host can't cope with that conversion,
but needs R1B, which means MMC_CAP_NEED_RSP_BUSY is set for them. Let's
take this into account, via using the common mmc_prepare_busy_cmd() when
doing the validation, which also avoids some open coding.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-3-ulf.hansson@linaro.org
Similar code for validating the host->max_busy_timeout towards the current
command's busy timeout, exists in mmc_do_erase(), mmc_sleep() and
__mmc_switch(). Let's move the common code into a helper function.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210504161222.101536-2-ulf.hansson@linaro.org
tty_operations::chars_in_buffer is another hook which is expected to
return values >= 0. So make it explicit by the return type too -- use
unsigned int.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Cc: Jens Taprogge <jens.taprogge@taprogge.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Link: https://lore.kernel.org/r/20210505091928.22010-27-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Line disciplines expect a positive value or zero returned from
tty->ops->write_room (invoked by tty_write_room). So make this
assumption explicit by using unsigned int as a return value. Both of
tty->ops->write_room and tty_write_room.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Acked-by: Alex Elder <elder@linaro.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com> # xtensa
Acked-by: David Sterba <dsterba@suse.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Chris Zankel <chris@zankel.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Cc: Jens Taprogge <jens.taprogge@taprogge.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Scott Branden <scott.branden@broadcom.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Link: https://lore.kernel.org/r/20210505091928.22010-23-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Group the flow flags under a single struct called flow. The new struct
contains 'stopped' and 'tco_stopped' bools which used to be bits in a
bitfield. The struct also contains the lock protecting them to
potentially share the same cache line.
Note that commit c545b66c69 (tty: Serialize tcflow() with other tty
flow control changes) added a padding to the original bitfield. It was
for the bitfield to occupy a whole 64b word to avoid interferring stores
on Alpha (cannot we evaporate this arch with weird implications to C
code yet?). But it doesn't work as expected as the padding
(tty_struct::unused) is aligned to a 8B boundary too and occupies some
bytes from the next word.
So make it reliable by:
1) setting __aligned of the struct -- that aligns the start, and
2) making 'unsigned long unused[0]' as the last member of the struct --
pads the end.
This is also the perfect time to start the documentation of tty_struct
where all this lives. So we start by documenting what these bools
actually serve for. And why we do all the alignment dances. Only the few
up-to-date information from the Theodore's comment made it into this new
Kerneldoc comment.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/20210505091928.22010-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In command queueing mode, the cache isn't flushed via the mmc_flush_cache()
function, but instead by issuing a CMDQ_TASK_MGMT (CMD48) with a
FLUSH_CACHE opcode. In this path, we need to check if cache has been
enabled, before deciding to flush the cache, along the lines of what's
being done in mmc_flush_cache().
To fix this problem, let's add a new bus ops callback ->cache_enabled() and
implement it for the mmc bus type. In this way, the mmc block device driver
can call it to know whether cache flushing should be done.
Fixes: 1e8e55b670 (mmc: block: Add CQE support)
Cc: stable@vger.kernel.org
Reported-by: Brendan Peter <bpeter@lytx.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Tested-by: Brendan Peter <bpeter@lytx.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210425060207.2591-2-avri.altman@wdc.com
Link: https://lore.kernel.org/r/20210425060207.2591-3-avri.altman@wdc.com
[Ulf: Squashed the two patches and made some minor updates]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The cache function can be turned ON and OFF by writing to the CACHE_CTRL
byte (EXT_CSD byte [33]). However, card->ext_csd.cache_ctrl is only
set on init if cache size > 0.
Fix that by explicitly setting ext_csd.cache_ctrl on ext-csd write.
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210420134641.57343-3-avri.altman@wdc.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
mmc_of_parse() for a few years has been using device property API.
Convert mmc_of_parse_voltage() as well.
At the same time switch users to new API.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210419112459.25241-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Since it has been converted to use device property API, the function
and field descriptions become outdated. Correct them.
Fixes: 73a47a9bb3 ("mmc: core: Use device_property_read instead of of_property_read")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210419112459.25241-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Not all commands need to be retried in case of a timeout/failure. This is
the case for the eMMC sanitize command, for example, which is issued
through the ioctl interface. More precisely, in case of timeout, retrying
could make the user wait for a very long time as each retry loop could last
for a couple of minutes.
Therefore, let's not use retries for the eMMC sanitize command.
Signed-off-by: Bean Huo <beanhuo@micron.com>
Link: https://lore.kernel.org/r/20210414212236.346813-3-huobean@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Add command retries parameter to __mmc_switch(), let caller
pass retries according to the caller's condition.
Signed-off-by: Bean Huo <beanhuo@micron.com>
Link: https://lore.kernel.org/r/20210414212236.346813-2-huobean@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As the density increases, the 4-minute timeout value for sanitize is no
longer feasible. At the same time, devices of different densities have
different timeout values, which makes it difficult to use a common timeout
value. Therefore, let's pass down the userland-specified sanitize timeout
value so it can be used.
Signed-off-by: Bean Huo <beanhuo@micron.com>
Link: https://lore.kernel.org/r/20210402092432.25069-2-huobean@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The mmc core uses a PM notifier to temporarily during system suspend, turn
off the card detection mechanism for removal/insertion of (e)MMC/SD/SDIO
cards. Additionally, the notifier may be used to remove an SDIO card
entirely, if a corresponding SDIO functional driver don't have the system
suspend/resume callbacks assigned. This behaviour has been around for a
very long time.
However, a recent bug report tells us there are problems with this
approach. More precisely, when receiving the PM_SUSPEND_PREPARE
notification, we may end up hanging on I/O to be completed, thus also
preventing the system from getting suspended.
In the end what happens, is that the cancel_delayed_work_sync() in
mmc_pm_notify() ends up waiting for mmc_rescan() to complete - and since
mmc_rescan() wants to claim the host, it needs to wait for the I/O to be
completed first.
Typically, this problem is triggered in Android, if there is ongoing I/O
while the user decides to suspend, resume and then suspend the system
again. This due to that after the resume, an mmc_rescan() work gets punted
to the workqueue, which job is to verify that the card remains inserted
after the system has resumed.
To fix this problem, userspace needs to become frozen to suspend the I/O,
prior to turning off the card detection mechanism. Therefore, let's drop
the PM notifiers for mmc subsystem altogether and rely on the card
detection to be turned off/on as a part of the system_freezable_wq, that we
are already using.
Moreover, to allow and SDIO card to be removed during system suspend, let's
manage this from a ->prepare() callback, assigned at the mmc_host_class
level. In this way, we can use the parent device (the mmc_host_class
device), to remove the card device that is the child, in the
device_prepare() phase.
Reported-by: Kiwoong Kim <kwmad.kim@samsung.com>
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210310152900.149380-1-ulf.hansson@linaro.org
Reviewed-by: Kiwoong Kim <kwmad.kim@samsung.com>
The host->cqe_enabled is already containing the needed information about
whether the CQE is enabled or not, hence there is no need to keep another
copy of it around.
Signed-off-by: Luca Porzio <lporzio@micron.com>
Signed-off-by: Zhan Liu <zliua@micron.com>
Link: https://lore.kernel.org/r/20210215003217.GA12240@lupo-laptop
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Returning zero to indicate success, when we actually have failed to probe
is wrong. As a matter of fact, it leads to that mmc_blk_remove() gets
called at a card removal and then triggers "NULL pointer dereference"
splats. This is because mmc_blk_remove() relies on data structures and
pointers to be setup from mmc_blk_probe(), of course.
There have been no errors reported about this, which is most likely because
mmc_blk_probe() never fails like this. Nevertheless, let's fix the code by
propagating the error codes correctly and prevent us from leaking memory by
calling also destroy_workqueue() in the error path.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-4-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
To simplify the code, move the logging into the common mmc_blk_alloc_req()
and drop the rather useless information about the partition type/id.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-3-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
mmc_blk_probe() isn't a hotpath, which makes it's questionable to use
unlikely(). Therefore let's simply drop it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-2-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Some of SD cards sets permanent write protection bit in their CSD register,
due to lifespan or internal problem. To avoid unnecessary I/O write
operations, let's parse the bits in the CSD during initialization and mark
the card as read only for this case.
Signed-off-by: Seunghui Lee <sh043.lee@samsung.com>
Link: https://lore.kernel.org/r/20210222083156.19158-1-sh043.lee@samsung.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
mmc_spi_send_{csd|cid} have similar function body. Let's remove the
duplicated part to simplify the code, just add opcode to distinguish
them in changed mmc_spi_send_cxd().
Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20210215015116.1355-1-zbestahu@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
When the mmc_rescan work is enabled for execution (host->rescan_disable),
it's the only instance per mmc host that is allowed to set/clear the
host->bus_ops pointer.
Besides the mmc_rescan work, there are a couple of scenarios when the
host->bus_ops pointer may be accessed. Typically, those can be described as
as below:
*)
Upper mmc driver layers (like the mmc block device driver or an SDIO
functional driver) needs to execute a host->bus_ops callback. This can be
considered as safe without having to use some special locking mechanism,
because they operate on top of the struct mmc_card. As long as there is a
card to operate upon, the mmc core guarantees that there is a host->bus_ops
assigned as well. Note that, upper layer mmc drivers are of course
responsible to clean up from themselves from their ->remove() callbacks,
otherwise things would fall apart anyways.
**)
Via the mmc host instance, we may need to force a removal of an inserted
mmc card. This happens when a mmc host driver gets unbind, for example. In
this case, we protect the host->bus_ops pointer from concurrent accesses,
by disabling the mmc_rescan work upfront (host->rescan_disable). See
mmc_stop_host() for example.
This said, it seems like the reference counting of the host->bus_ops
pointer at some point have become superfluous. As this is an old mechanism
of the mmc core, it a bit difficult to digest the history of when that
could have happened. However, let's drop the reference counting to avoid
unnecessary code-paths and lockings.
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210212131610.236843-1-ulf.hansson@linaro.org
The mmc_hw|sw_reset() APIs are designed to be called solely from upper
layers, which means drivers that operates on top of the struct mmc_card,
like the mmc block device driver and an SDIO functional driver.
Additionally, as long as the struct mmc_host has a valid pointer to a
struct mmc_card, the corresponding host->bus_ops pointer stays valid and
assigned.
For these reasons, let's drop the superfluous reference counting and the
redundant validations in mmc_hw|sw_reset().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210212131532.236775-1-ulf.hansson@linaro.org
A CMD11 is sent to the SD/SDIO card to start the voltage switch procedure
into 1.8V I/O. According to the SD spec a power cycle is needed of the
card, if it turns out that the CMD11 fails. Let's fix this, to allow a
retry of the initialization without the voltage switch, to succeed.
Note that, whether it makes sense to also retry with the voltage switch
after the power cycle is a bit more difficult to know. At this point, we
treat it like the CMD11 isn't supported and therefore we skip it when
retrying.
Signed-off-by: DooHyun Hwang <dh0421.hwang@samsung.com>
Link: https://lore.kernel.org/r/20210210045936.7809-1-dh0421.hwang@samsung.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
