dax: mark dax_get_by_host static

And move the code around a bit to avoid a forward declaration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Li

dax: mark dax_get_by_host static

And move the code around a bit to avoid a forward declaration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210826135510.6293-5-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dax: stop using bdevname

Just use the %pg format specifier instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/

dax: stop using bdevname

Just use the %pg format specifier instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210826135510.6293-3-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dax: Ensure errno is returned from dax_direct_access

If the caller specifies a negative nr_pages that is an invalid
parameter.

Return -EINVAL to ensure callers get an errno if they want to check it

dax: Ensure errno is returned from dax_direct_access

If the caller specifies a negative nr_pages that is an invalid
parameter.

Return -EINVAL to ensure callers get an errno if they want to check it.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210525172428.3634316-4-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

whack-a-mole: don't open-code iminor/imajor

several instances creeped back into the tree...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

device-dax/core: Fix memory leak when rmmod dax.ko

When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
memory leak as follows:

unreferenced object 0xffff9a5588c05088 (size 8):
comm "mo

device-dax/core: Fix memory leak when rmmod dax.ko

When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
memory leak as follows:

unreferenced object 0xffff9a5588c05088 (size 8):
comm "modprobe", pid 261, jiffies 4294693644 (age 42.063s)
...
backtrace:
[<00000000e007ced0>] kstrdup+0x35/0x70
[<000000002ae73897>] kstrdup_const+0x3d/0x50
[<000000002b00c9c3>] kvasprintf_const+0xbc/0xf0
[<000000008023282f>] kobject_set_name_vargs+0x3b/0xd0
[<00000000d2cbaa4e>] kobject_set_name+0x62/0x90
[<00000000202e7a22>] bus_register+0x7f/0x2b0
[<000000000b77792c>] 0xffffffffc02840f7
[<000000002d5be5ac>] 0xffffffffc02840b4
[<00000000dcafb7cd>] do_one_initcall+0x58/0x240
[<00000000049fe480>] do_init_module+0x56/0x1e2
[<0000000022671491>] load_module+0x2517/0x2840
[<000000001a2201cb>] __do_sys_finit_module+0x9c/0xe0
[<000000003eb304e7>] do_syscall_64+0x33/0x40
[<0000000051c5fd06>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

When rmmod dax is executed, dax_bus_exit() is missing. This patch
can fix this bug.

Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model")
Cc: <stable@vger.kernel.org>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20201201135929.66530-1-wanghai38@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

device-dax/core: Fix memory leak when rmmod dax.ko

commit 1aa574312518ef1d60d2dc62d58f7021db3b163a upstream.

When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
memory leak as follows:

device-dax/core: Fix memory leak when rmmod dax.ko

commit 1aa574312518ef1d60d2dc62d58f7021db3b163a upstream.

When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
memory leak as follows:

unreferenced object 0xffff9a5588c05088 (size 8):
comm "modprobe", pid 261, jiffies 4294693644 (age 42.063s)
...
backtrace:
[<00000000e007ced0>] kstrdup+0x35/0x70
[<000000002ae73897>] kstrdup_const+0x3d/0x50
[<000000002b00c9c3>] kvasprintf_const+0xbc/0xf0
[<000000008023282f>] kobject_set_name_vargs+0x3b/0xd0
[<00000000d2cbaa4e>] kobject_set_name+0x62/0x90
[<00000000202e7a22>] bus_register+0x7f/0x2b0
[<000000000b77792c>] 0xffffffffc02840f7
[<000000002d5be5ac>] 0xffffffffc02840b4
[<00000000dcafb7cd>] do_one_initcall+0x58/0x240
[<00000000049fe480>] do_init_module+0x56/0x1e2
[<0000000022671491>] load_module+0x2517/0x2840
[<000000001a2201cb>] __do_sys_finit_module+0x9c/0xe0
[<000000003eb304e7>] do_syscall_64+0x33/0x40
[<0000000051c5fd06>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

When rmmod dax is executed, dax_bus_exit() is missing. This patch
can fix this bug.

Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model")
Cc: <stable@vger.kernel.org>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20201201135929.66530-1-wanghai38@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

dax: Fix stack overflow when mounting fsdax pmem device

When mounting fsdax pmem device, commit 6180bb446ab6 ("dax: fix
detection of dax support for non-persistent memory block devices")
introduces

dax: Fix stack overflow when mounting fsdax pmem device

When mounting fsdax pmem device, commit 6180bb446ab6 ("dax: fix
detection of dax support for non-persistent memory block devices")
introduces the stack overflow [1][2]. Here is the call path for
mounting ext4 file system:
ext4_fill_super
bdev_dax_supported
__bdev_dax_supported
dax_supported
generic_fsdax_supported
__generic_fsdax_supported
bdev_dax_supported

The call path leads to the infinite calling loop, so we cannot
call bdev_dax_supported() in __generic_fsdax_supported(). The sanity
checking of the variable 'dax_dev' is moved prior to the two
bdev_dax_pgoff() checks [3][4].

[1] https://lore.kernel.org/linux-nvdimm/1420999447.1004543.1600055488770.JavaMail.zimbra@redhat.com/
[2] https://lore.kernel.org/linux-nvdimm/alpine.LRH.2.02.2009141131220.30651@file01.intranet.prod.int.rdu2.redhat.com/
[3] https://lore.kernel.org/linux-nvdimm/CA+RJvhxBHriCuJhm-D8NvJRe3h2MLM+ZMFgjeJjrRPerMRLvdg@mail.gmail.com/
[4] https://lore.kernel.org/linux-nvdimm/20200903160608.GU878166@iweiny-DESK2.sc.intel.com/

Fixes: 6180bb446ab6 ("dax: fix detection of dax support for non-persistent memory block devices")
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Ritesh Harjani <riteshh@linux.ibm.com>
Cc: Coly Li <colyli@suse.de>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: John Pittman <jpittman@redhat.com>
Link: https://lore.kernel.org/r/20200917111549.6367-1-adrianhuang0701@gmail.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dm: Call proper helper to determine dax support

DM was calling generic_fsdax_supported() to determine whether a device
referenced in the DM table supports DAX. However this is a helper for "leaf" de

dm: Call proper helper to determine dax support

DM was calling generic_fsdax_supported() to determine whether a device
referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that
they don't have to duplicate common generic checks. High level code
should call dax_supported() helper which that calls into appropriate
helper for the particular device. This problem manifested itself as
kernel messages:

dm-3: error: dax access failed (-95)

when lvm2-testsuite run in cases where a DM device was stacked on top of
another DM device.

Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices")
Cc: <stable@vger.kernel.org>
Tested-by: Adrian Huang <ahuang12@lenovo.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dax: Modify bdev_dax_pgoff() to handle NULL bdev

virtiofs does not have a block device but it has dax device.
Modify bdev_dax_pgoff() to be able to handle that.

If there is no bdev, that means dax

dax: Modify bdev_dax_pgoff() to handle NULL bdev

virtiofs does not have a block device but it has dax device.
Modify bdev_dax_pgoff() to be able to handle that.

If there is no bdev, that means dax offset is 0. (It can't be a partition
block device starting at an offset in dax device).

This is little hackish. There have been discussions about getting rid
of dax not supporting partitions.

https://lore.kernel.org/linux-fsdevel/20200107125159.GA15745@infradead.org/

IMHO, this path can easily break exisitng users. For example
ioctl(BLKPG_ADD_PARTITION) will start breaking on block devices
supporting DAX. Also, I personally find it very useful to be able to
partition dax devices and still be able to use DAX.

Alternatively, I tried to store offset into dax device information in iomap
interface, but that got NACKed.

https://lore.kernel.org/linux-fsdevel/20200217133117.GB20444@infradead.org/

I can't think of a good path to solve this issue properly. So to make
progress, it seems this patch is least bad option for now and I hope
we can take it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Cc: "Weiny, Ira" <ira.weiny@intel.com>
Cc: linux-nvdimm@lists.01.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

show more ...

dax: fix detection of dax support for non-persistent memory block devices

When calling __generic_fsdax_supported(), a dax-unsupported device may
not have dax_dev as NULL, e.g. the dax related code b

dax: fix detection of dax support for non-persistent memory block devices

When calling __generic_fsdax_supported(), a dax-unsupported device may
not have dax_dev as NULL, e.g. the dax related code block is not enabled
by Kconfig.

Therefore in __generic_fsdax_supported(), to check whether a device
supports DAX or not, the following order of operations should be
performed:
- If dax_dev pointer is NULL, it means the device driver explicitly
announce it doesn't support DAX. Then it is OK to directly return
false from __generic_fsdax_supported().
- If dax_dev pointer is NOT NULL, it might be because the driver doesn't
support DAX and not explicitly initialize related data structure. Then
bdev_dax_supported() should be called for further check.

If device driver desn't explicitly set its dax_dev pointer to NULL,
this is not a bug. Calling bdev_dax_supported() makes sure they can be
recognized as dax-unsupported eventually.

Fixes: c2affe920b0e ("dax: do not print error message for non-persistent memory block device")
Cc: Jan Kara <jack@suse.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-and-tested-by: Adrian Huang <ahuang12@lenovo.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/20200903161625.19524-1-colyli@suse.de

show more ...

dax: do not print error message for non-persistent memory block device

Commit 231609785cbf ("dax: print error message by pr_info()
in __generic_fsdax_supported()") happens to print the following
err

dax: do not print error message for non-persistent memory block device

Commit 231609785cbf ("dax: print error message by pr_info()
in __generic_fsdax_supported()") happens to print the following
error message during booting when the non-persistent memory block
devices are configured by device mapper. Those error messages are
caused by the variable 'dax_dev' is NULL. Users might be confused
with those error messages since they do not use the persistent
memory device. Moreover, users might scare about "what's wrong
with my disks" because they see the 'error' and 'failed' keywords.

# dmesg | grep fail
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdk3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)
sdb3: error: dax access failed (-95)

# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 1.1T 0 disk
├─sda1 8:1 0 156M 0 part
├─sda2 8:2 0 40G 0 part
└─sda3 8:3 0 1.1T 0 part
sdb 8:16 0 1.1T 0 disk
├─sdb1 8:17 0 600M 0 part
├─sdb2 8:18 0 1G 0 part
└─sdb3 8:19 0 1.1T 0 part
├─rhel00-swap 254:3 0 4G 0 lvm
├─rhel00-home 254:4 0 1T 0 lvm
└─rhel00-root 254:5 0 50G 0 lvm
sdc 8:32 0 1.1T 0 disk
sdd 8:48 0 1.1T 0 disk
sde 8:64 0 1.1T 0 disk
sdf 8:80 0 1.1T 0 disk
sdg 8:96 0 1.1T 0 disk
sdh 8:112 0 3.3T 0 disk
├─sdh1 8:113 0 500M 0 part /boot/efi
├─sdh2 8:114 0 40G 0 part /
├─sdh3 8:115 0 2.9T 0 part /home
└─sdh4 8:116 0 314.6G 0 part [SWAP]
sdi 8:128 0 1.1T 0 disk
sdj 8:144 0 3.3T 0 disk
├─sdj1 8:145 0 512M 0 part
└─sdj2 8:146 0 3.3T 0 part
sdk 8:160 0 119.2G 0 disk
├─sdk1 8:161 0 200M 0 part
├─sdk2 8:162 0 1G 0 part
└─sdk3 8:163 0 118G 0 part
├─rhel-swap 254:0 0 4G 0 lvm
├─rhel-home 254:1 0 64G 0 lvm
└─rhel-root 254:2 0 50G 0 lvm
sdl 8:176 0 119.2G 0 disk

The call path is shown as follows:
dm_table_determine_type
dm_table_supports_dax
device_supports_dax
generic_fsdax_supported
__generic_fsdax_supported

With the disk configuration listing from the command 'lsblk',
the member 'dev->dax_dev' of the block devices 'sdb3' and 'sdk3'
(configured by device mapper) is NULL in function
generic_fsdax_supported() because the member is configured in
function open_table_device().

To prevent the confusing error messages in this scenario (this is
normal behavior), just print those error messages by pr_debug()
by checking if dax_dev is NULL and the block device does not support
DAX.

Link: https://lore.kernel.org/r/20200819154236.24191-1-adrianhuang0701@gmail.com
Fixes: 231609785cbf ("dax: print error message by pr_info() in __generic_fsdax_supported()")
Cc: Coly Li <colyli@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

show more ...

drivers/dax: Expand lock scope to cover the use of addresses

The addition of PKS protection to dax read lock/unlock will require that
the address returned by dax_direct_access() be protected by this

drivers/dax: Expand lock scope to cover the use of addresses

The addition of PKS protection to dax read lock/unlock will require that
the address returned by dax_direct_access() be protected by this lock.

Correct the locking by ensuring that the use of kaddr and end_kaddr
are covered by the dax read lock/unlock.

Link: https://lore.kernel.org/r/20200717072056.73134-12-ira.weiny@intel.com
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

show more ...

dax: print error message by pr_info() in __generic_fsdax_supported()

In struct dax_operations, the callback routine dax_supported() returns
a bool type result. For false return value, the caller has

dax: print error message by pr_info() in __generic_fsdax_supported()

In struct dax_operations, the callback routine dax_supported() returns
a bool type result. For false return value, the caller has no idea
whether the device does not support dax at all, or it is just some mis-
configuration issue.

An example is formatting an Ext4 file system on pmem device on top of
a NVDIMM namespace by,
# mkfs.ext4 /dev/pmem0
If the fs block size does not match kernel space memory page size (which
is possible on non-x86 platform), mount this Ext4 file system will fail,
# mount -o dax /dev/pmem0 /mnt
mount: /mnt: wrong fs type, bad option, bad superblock on /dev/pmem0,
missing codepage or helper program, or other error.
And from the dmesg output there is only the following information,
[ 307.853148] EXT4-fs (pmem0): DAX unsupported by block device.

The above information is quite confusing. Because definitely the pmem0
device supports dax operation, and the super block is consistent as how
it was created by mkfs.ext4.

Indeed the failure is from __generic_fsdax_supported() by the following
code piece,
if (blocksize != PAGE_SIZE) {
pr_debug("%s: error: unsupported blocksize for dax\n",
bdevname(bdev, buf));
return false;
}
It is because the Ext4 block size is 4KB and kernel page size is 8KB or
16KB.

It is not simple to make dax_supported() from struct dax_operations
or __generic_fsdax_supported() to return exact failure type right now.
So the simplest fix is to use pr_info() to print all the error messages
inside __generic_fsdax_supported(). Then users may find informative clue
from the kernel message at least.

Message printed by pr_debug() is very easy to be ignored by users. This
patch prints error message by pr_info() in __generic_fsdax_supported(),
when then mount fails, following lines can be found from dmesg output,
[ 2705.500885] pmem0: error: unsupported blocksize for dax
[ 2705.500888] EXT4-fs (pmem0): DAX unsupported by block device.
Now the users may have idea the mount failure is from pmem driver for
unsupported block size.

Link: https://lore.kernel.org/r/20200725162450.95999-1-colyli@suse.de
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Anthony Iliopoulos <ailiopoulos@suse.com>
Reported-by: Michal Suchanek <msuchanek@suse.com>
Suggested-by: Jan Kara <jack@suse.com>
Reviewed-by: Jan Kara <jack@suse.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

show more ...

block: remove the bd_queue field from struct block_device

Just use bd_disk->queue instead.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

block: remove the bd_queue field from struct block_device

Just use bd_disk->queue instead.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

dax: Move mandatory ->zero_page_range() check in alloc_dax()

zero_page_range() dax operation is mandatory for dax devices. Right now
that check happens in dax_zero_page_range() function. Dan thinks

dax: Move mandatory ->zero_page_range() check in alloc_dax()

zero_page_range() dax operation is mandatory for dax devices. Right now
that check happens in dax_zero_page_range() function. Dan thinks that's
too late and its better to do the check earlier in alloc_dax().

I also modified alloc_dax() to return pointer with error code in it in
case of failure. Right now it returns NULL and caller assumes failure
happened due to -ENOMEM. But with this ->zero_page_range() check, I
need to return -EINVAL instead.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: https://lore.kernel.org/r/20200401161125.GB9398@redhat.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dax, pmem: Add a dax operation zero_page_range

Add a dax operation zero_page_range, to zero a page. This will also clear any
known poison in the page being zeroed.

As of now, zeroing of one page is

dax, pmem: Add a dax operation zero_page_range

Add a dax operation zero_page_range, to zero a page. This will also clear any
known poison in the page being zeroed.

As of now, zeroing of one page is allowed in a single call. There
are no callers which are trying to zero more than a page in a single call.
Once we grow the callers which zero more than a page in single call, we
can add that support. Primary reason for not doing that yet is that this
will add little complexity in dm implementation where a range might be
spanning multiple underlying targets and one will have to split the range
into multiple sub ranges and call zero_page_range() on individual targets.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Link: https://lore.kernel.org/r/20200228163456.1587-3-vgoyal@redhat.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

dax: Get rid of fs_dax_get_by_host() helper

Looks like nobody is using fs_dax_get_by_host() except fs_dax_get_by_bdev()
and it can easily use dax_get_by_host() instead.

IIUC, fs_dax_get_by_host() w

dax: Get rid of fs_dax_get_by_host() helper

Looks like nobody is using fs_dax_get_by_host() except fs_dax_get_by_bdev()
and it can easily use dax_get_by_host() instead.

IIUC, fs_dax_get_by_host() was only introduced so that one could compile
with CONFIG_FS_DAX=n and CONFIG_DAX=m. fs_dax_get_by_bdev() achieves
the same purpose and hence it looks like fs_dax_get_by_host() is not
needed anymore.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200106181117.GA16248@redhat.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

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libnvdimm: add dax_dev sync flag

This patch adds 'DAXDEV_SYNC' flag which is set
for nd_region doing synchronous flush. This later
is used to disable MAP_SYNC functionality for
ext4 & xfs filesystem

libnvdimm: add dax_dev sync flag

This patch adds 'DAXDEV_SYNC' flag which is set
for nd_region doing synchronous flush. This later
is used to disable MAP_SYNC functionality for
ext4 & xfs filesystem for devices don't support
synchronous flush.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of ve

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 64 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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vfs: Convert dax to use the new mount API

Convert the dax filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of

vfs: Convert dax to use the new mount API

Convert the dax filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Dan Williams <dan.j.williams@intel.com>
cc: Vishal Verma <vishal.l.verma@intel.com>
cc: Keith Busch <keith.busch@intel.com>
cc: Dave Jiang <dave.jiang@intel.com>
cc: linux-nvdimm@lists.01.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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mount_pseudo(): drop 'name' argument, switch to d_make_root()

Once upon a time we used to set ->d_name of e.g. pipefs root
so that d_path() on pipes would work. These days it's
completely pointless

mount_pseudo(): drop 'name' argument, switch to d_make_root()

Once upon a time we used to set ->d_name of e.g. pipefs root
so that d_path() on pipes would work. These days it's
completely pointless - dentries of pipes are not even connected
to pipefs root. However, mount_pseudo() had set the root
dentry name (passed as the second argument) and callers
kept inventing names to pass to it. Including those that
didn't *have* any non-root dentries to start with...

All of that had been pointless for about 8 years now; it's
time to get rid of that cargo-culting...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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device-dax: Drop register_filesystem()

The device-dax fs is only there to allocate a common inode for each
device-node that refers to the same device by major:minor. It is
otherwise not user mountab

device-dax: Drop register_filesystem()

The device-dax fs is only there to allocate a common inode for each
device-node that refers to the same device by major:minor. It is
otherwise not user mountable and need not be displayed in
/proc/filesystems.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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dax: Arrange for dax_supported check to span multiple devices

Pankaj reports that starting with commit ad428cdb525a "dax: Check the
end of the block-device capacity with dax_direct_access()" device-

dax: Arrange for dax_supported check to span multiple devices

Pankaj reports that starting with commit ad428cdb525a "dax: Check the
end of the block-device capacity with dax_direct_access()" device-mapper
no longer allows dax operation. This results from the stricter checks in
__bdev_dax_supported() that validate that the start and end of a
block-device map to the same 'pagemap' instance.

Teach the dax-core and device-mapper to validate the 'pagemap' on a
per-target basis. This is accomplished by refactoring the
bdev_dax_supported() internals into generic_fsdax_supported() which
takes a sector range to validate. Consequently generic_fsdax_supported()
is suitable to be used in a device-mapper ->iterate_devices() callback.
A new ->dax_supported() operation is added to allow composite devices to
split and route upper-level bdev_dax_supported() requests.

Fixes: ad428cdb525a ("dax: Check the end of the block-device...")
Cc: <stable@vger.kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Pankaj Gupta <pagupta@redhat.com>
Tested-by: Pankaj Gupta <pagupta@redhat.com>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

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dax: make use of ->free_inode()

we might want to drop ->destroy_inode() there - it's used only for
WARN_ON() now, and AFAICS that could be moved to ->evict_inode()
if we had one...

Reviewed-by: Jan

dax: make use of ->free_inode()

we might want to drop ->destroy_inode() there - it's used only for
WARN_ON() now, and AFAICS that could be moved to ->evict_inode()
if we had one...

Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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dax: Check the end of the block-device capacity with dax_direct_access()

The checks in __bdev_dax_supported() helped mitigate a potential data
corruption bug in the pmem driver's handling of section

dax: Check the end of the block-device capacity with dax_direct_access()

The checks in __bdev_dax_supported() helped mitigate a potential data
corruption bug in the pmem driver's handling of section alignment
padding. Strengthen the checks, including checking the end of the range,
to validate the dev_pagemap, Xarray entries, and sector-to-pfn
translation established for pmem namespaces.

Acked-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

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