The trigger_dump file is only used to manually trigger the dump, and did
not provide a read callback function for it, so its file permission
setting to 600 is wrong,and should be changed to 200.
Link: https://lore.kernel.org/r/1579522957-4393-5-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We use magic number as offset and mask when handle channel interrupt, so
use macro to replace it.
Link: https://lore.kernel.org/r/1579522957-4393-4-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
After changing tasklet to workqueue or threaded irq, some critical
resources are only used on threads (not in interrupt or bottom half of
interrupt), so replace spin_lock_irqsave/spin_unlock_restore with
spin_lock/spin_unlock to protect those critical resources.
Link: https://lore.kernel.org/r/1579522957-4393-3-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently IRQ_EFFECTIVE_AFF_MASK is enabled for ARM_GIC and ARM_GIC3, so it
only allows a single target CPU in the affinity mask to process interrupts
and also interrupt thread, and the performance of using threaded irq is
almost the same as tasklet. But if the config is not enabled, the interrupt
thread will be allowed all the CPUs in the affinity mask. At that situation
it improves the performance (about 20%).
Note: IRQ_EFFECTIVE_AFF_MASK is configured differently for different
architecture chip, and it seems to be better to make it be configured
easily.
Link: https://lore.kernel.org/r/1579522957-4393-2-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The ata_sas_scsi_ioctl() function implements a number of HDIO_* commands
for SCSI devices, it is used by all libata drivers as well as a few
drivers that support SAS attached SATA drives.
The only command that is not safe for compat ioctls here is
HDIO_GET_32BIT. Change the implementation to check for in_compat_syscall()
in order to do both cases correctly, and change all callers to use it
as both native and compat callback pointers, including the indirect
callers through sas_ioctl and ata_scsi_ioctl.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Currently we call function hisi_sas_debugfs_exit() to remove debugfs_dir
before freeing interrupt irqs and destroying workqueue in the driver remove
path.
If a dump is triggered before function hisi_sas_debugfs_exit() but
debugfs_work may be called after it, so it may refer to already removed
debugfs_dir which will cause NULL pointer dereference.
To avoid it, put function hisi_sas_debugfs_exit() after free_irqs and
destroy workqueue when removing hisi_sas driver.
Link: https://lore.kernel.org/r/1573551059-107873-4-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Need to return directly if init hardware failed.
Fixes: 73a4925d15 ("scsi: hisi_sas: Update all the registers after suspend and resume")
Link: https://lore.kernel.org/r/1573551059-107873-3-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The number of phy down reflects the quality of the link between SAS
controller and disk. In order to allow the user to confirm the link quality
of the system, we record the number of phy down for each phy.
The user can check the current phy down count by reading the debugfs file
corresponding to the specific phy, or clear the phy down count by writing 0
to the debugfs file.
Link: https://lore.kernel.org/r/1571926105-74636-19-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Although if the debugfs initialization fails, we will delete the debugfs
folder of hisi_sas, but we did not consider the scenario where debugfs was
successfully initialized, but the probe failed for other reasons. We found
out that hisi_sas folder is still remain after the probe failed.
When probe fail, we should delete debugfs folder to avoid the above issue.
Link: https://lore.kernel.org/r/1571926105-74636-18-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We use the module parameter debugfs_dump_count to manage the upper limit of
the memory block for multiple dumps.
Link: https://lore.kernel.org/r/1571926105-74636-17-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We add multiple dumps for debugfs, but only allocate memory this time and
only dump #0.
Link: https://lore.kernel.org/r/1571926105-74636-15-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address for
ITCT cache at debugfs. This structure is bound to the corresponding debugfs
file, it can help callback function of debugfs file to get what it needs.
Link: https://lore.kernel.org/r/1571926105-74636-14-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address for IOST
cache at debugfs. This structure is bound to the corresponding debugfs
file, it can help callback function of debugfs file to get what it needs.
Link: https://lore.kernel.org/r/1571926105-74636-13-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address for ITCT
at debugfs. This structure is bound to the corresponding debugfs file, it
can help callback function of debugfs file to get what it needs.
Link: https://lore.kernel.org/r/1571926105-74636-12-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address for IOST
at debugfs. This structure is bound to the corresponding debugfs file, it
can help callback function of debugfs file to get what it needs.
Link: https://lore.kernel.org/r/1571926105-74636-11-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address and phy
pointer for port at debugfs. This structure is bound to the corresponding
debugfs file, it can help callback function of debugfs file to get what it
need.
Link: https://lore.kernel.org/r/1571926105-74636-10-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address and
hisi_hba pointer for REGS at debugfs. This structure is bound to the
corresponding debugfs file, it can help callback function of debugfs file
to get what it need.
Link: https://lore.kernel.org/r/1571926105-74636-9-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address and DQ
pointer for DQ at debugfs. This structure is bound to the corresponding
debugfs file, it can help callback function of debugfs file to get what it
need.
Link: https://lore.kernel.org/r/1571926105-74636-8-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Create a file structure which was used to save the memory address and CQ
pointer for CQ at debugfs. This structure is bound to the corresponding
debugfs file, it can help callback function of debugfs file to get what it
need.
Link: https://lore.kernel.org/r/1571926105-74636-7-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
It's useful to know when the dump occurred, so add a timestamp file for
this.
Link: https://lore.kernel.org/r/1571926105-74636-6-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
For IOs from upper layer, preemption may be disabled as it may be called by
function __blk_mq_delay_run_hw_queue which will call get_cpu() (it disables
preemption). So if flags HISI_SAS_REJECT_CMD_BIT is set in function
hisi_sas_task_exec(), it may disable preempt twice after down() and up()
which will cause following call trace:
BUG: scheduling while atomic: fio/60373/0x00000002
Call trace:
dump_backtrace+0x0/0x150
show_stack+0x24/0x30
dump_stack+0xa0/0xc4
__schedule_bug+0x68/0x88
__schedule+0x4b8/0x548
schedule+0x40/0xd0
schedule_timeout+0x200/0x378
__down+0x78/0xc8
down+0x54/0x70
hisi_sas_task_exec.isra.10+0x598/0x8d8 [hisi_sas_main]
hisi_sas_queue_command+0x28/0x38 [hisi_sas_main]
sas_queuecommand+0x168/0x1b0 [libsas]
scsi_queue_rq+0x2ac/0x980
blk_mq_dispatch_rq_list+0xb0/0x550
blk_mq_do_dispatch_sched+0x6c/0x110
blk_mq_sched_dispatch_requests+0x114/0x1d8
__blk_mq_run_hw_queue+0xb8/0x130
__blk_mq_delay_run_hw_queue+0x1c0/0x220
blk_mq_run_hw_queue+0xb0/0x128
blk_mq_sched_insert_requests+0xdc/0x208
blk_mq_flush_plug_list+0x1b4/0x3a0
blk_flush_plug_list+0xdc/0x110
blk_finish_plug+0x3c/0x50
blkdev_direct_IO+0x404/0x550
generic_file_read_iter+0x9c/0x848
blkdev_read_iter+0x50/0x78
aio_read+0xc8/0x170
io_submit_one+0x1fc/0x8d8
__arm64_sys_io_submit+0xdc/0x280
el0_svc_common.constprop.0+0xe0/0x1e0
el0_svc_handler+0x34/0x90
el0_svc+0x10/0x14
...
To solve the issue, check preemptible() to avoid disabling preempt multiple
when flag HISI_SAS_REJECT_CMD_BIT is set.
Link: https://lore.kernel.org/r/1571926105-74636-5-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When injecting 2bit ecc errors, it will cause confusion inside SAS
controller which needs host reset to recover it. If a device is gone at the
same times inject 2bit ecc errors, we may not receive the ITCT interrupt so
it will wait for completion in clear_itct_v3_hw() all the time. And host
reset will also not occur because it can't require hisi_hba->sem, so the
system will be suspended.
To solve the issue, use wait_for_completion_timeout() instead of
wait_for_completion(), and also don't mark the gone device as
SAS_PHY_UNUSED when device gone.
Link: https://lore.kernel.org/r/1571926105-74636-4-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If set the BIST init value after enabling BIST, there may be still some few
error bits. According to the process, need to set the BIST init value
before enabling BIST.
Fixes: 97b151e758 ("scsi: hisi_sas: Add BIST support for phy loopback")
Link: https://lore.kernel.org/r/1571926105-74636-3-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Due to a merge error, we attempt to create 2x debugfs dump folders, which
fails:
[ 861.101914] debugfs: Directory 'dump' with parent '0000:74:02.0'
already present!
This breaks the dump function.
To fix, remove the superfluous attempt to create the folder.
Fixes: 7ec7082c57 ("scsi: hisi_sas: Add hisi_sas_debugfs_alloc() to centralise allocation")
Link: https://lore.kernel.org/r/1571926105-74636-2-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Fix sparse warnings:
drivers/scsi/hisi_sas/hisi_sas_main.c:3686:6:
warning: symbol 'hisi_sas_debugfs_release' was not declared. Should it be static?
drivers/scsi/hisi_sas/hisi_sas_main.c:3708:5:
warning: symbol 'hisi_sas_debugfs_alloc' was not declared. Should it be static?
drivers/scsi/hisi_sas/hisi_sas_main.c:3799:6:
warning: symbol 'hisi_sas_debugfs_bist_init' was not declared. Should it be static?
Link: https://lore.kernel.org/r/20190923054035.19036-1-yuehaibing@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When device gone, it will check whether it is during reset, if not, it will
send internal task abort. Before internal task abort returned, reset
begins, and it will check whether SAS_PHY_UNUSED is set, if not, it will
call hisi_sas_init_device(), but at that time domain_device may already be
freed or part of it is freed, so it may referenece null pointer in
hisi_sas_init_device(). It may occur as follows:
thread0 thread1
hisi_sas_dev_gone()
check whether in RESET(no)
internal task abort
reset prep
soft_reset
... (part of reset_done)
internal task abort failed
release resource anyway
clear_itct
device->lldd_dev=NULL
hisi_sas_reset_init_all_device
check sas_dev->dev_type is SAS_PHY_UNUSED and
!device
set dev_type SAS_PHY_UNUSED
sas_free_device
hisi_sas_init_device
...
Semaphore hisi_hba.sema is used to sync the processes of device gone and
host reset.
To solve the issue, expand the scope that semaphore protects and let them
never occur together.
And also some places will check whether domain_device is NULL to judge
whether the device is gone. So when device gone, need to clear
sas_dev->sas_device.
Link: https://lore.kernel.org/r/1567774537-20003-14-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add BIST (built in self test) support for phy loopback.
Through the new debugfs interface, the user can configure loopback
mode/linkrate/phy id/code mode before enabling it. And also user can
enable/disable BIST function.
Link: https://lore.kernel.org/r/1567774537-20003-13-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We extract the code of memory allocate and construct an new function for
it. We think it's convenient for subsequent optimization.
Link: https://lore.kernel.org/r/1567774537-20003-12-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Some function arguments are unused, so remove them.
Also move the timeout print in for wait_cmds_complete_timeout_vX_hw()
callsites into that same function.
Link: https://lore.kernel.org/r/1567774537-20003-11-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently the NCQ tag is only assigned for FPDMA READ and FPDMA WRITE
commands, and for other NCQ commands (such as FPDMA SEND), their NCQ tags
are set in the delivery command to 0.
So for all the NCQ commands, we also need to assign normal NCQ tag for
them, so drop the command type check in hisi_sas_get_ncq_tag() [drop
hisi_sas_get_ncq_tag() altogether actually], and always use the ATA command
NCQ tag when appropriate.
Link: https://lore.kernel.org/r/1567774537-20003-8-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
After suspend and resume, the HW registers will be set back to their
initial value. We use init_reg_v3_hw() to set some registers, but some
registers are set via firmware in ACPI "_RST" method, so add reset handler
before init_reg_v3_hw().
Link: https://lore.kernel.org/r/1567774537-20003-7-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When init device for SAS disks, it will send TMF IO to clear disks. At that
time TMF IO is broken by some operations such as injecting controller reset
from HW RAs event, the TMF IO will be timeout, and at last device will be
gone. Print is as followed:
hisi_sas_v3_hw 0000:74:02.0: dev[240:1] found
...
hisi_sas_v3_hw 0000:74:02.0: controller resetting...
hisi_sas_v3_hw 0000:74:02.0: phyup: phy7 link_rate=10(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy0 link_rate=9(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy1 link_rate=9(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy2 link_rate=9(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy3 link_rate=9(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy6 link_rate=10(sata)
hisi_sas_v3_hw 0000:74:02.0: phyup: phy5 link_rate=11
hisi_sas_v3_hw 0000:74:02.0: phyup: phy4 link_rate=11
hisi_sas_v3_hw 0000:74:02.0: controller reset complete
hisi_sas_v3_hw 0000:74:02.0: abort tmf: TMF task timeout and not done
hisi_sas_v3_hw 0000:74:02.0: dev[240:1] is gone
sas: driver on host 0000:74:02.0 cannot handle device 5000c500a75a860d,
error:5
To improve the reliability, retry TMF IO max of 3 times for SAS disks which
is the same as softreset does.
Link: https://lore.kernel.org/r/1567774537-20003-6-git-send-email-john.garry@huawei.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
At expander environment, we delay after issue phy reset to wait for
hardware to handle phy reset. But if sas_smp_phy_control() fails, the
delay is unnecessary so remove it.
Link: https://lore.kernel.org/r/1567774537-20003-5-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
At hisi_sas_debug_I_T_nexus_reset(), we call sas_phy_reset() to reset a
phy. But if the phy is disabled, sas_phy_reset() will directly return
-ENODEV without issue a phy reset request.
If so, We can directly return -ENODEV to libsas before issue a phy
reset.
Link: https://lore.kernel.org/r/1567774537-20003-4-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When calling sas_phy_reset(), we need to specify whether the reset type
is hard reset or link reset - use true/false for clarity.
Link: https://lore.kernel.org/r/1567774537-20003-3-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.
Link: https://lore.kernel.org/r/20190904130256.24704-1-yuehaibing@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/scsi/hisi_sas/hisi_sas_v1_hw.c: In function cq_interrupt_v1_hw:
drivers/scsi/hisi_sas/hisi_sas_v1_hw.c:1542:6: warning: variable irq_value set but not used [-Wunused-but-set-variable]
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In hisi_sas_lu_reset(), we call internal abort for SAS and SATA device
codepaths -> consolidate into a single call.
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The format specifier "%p" can leak kernel address, and use "%pK" instead.
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove some unnecessary code, including:
- Explicit zeroing of memory allocated for dmam_alloc_coherent()
- Some duplicated code
- Some redundant masking
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
