| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
Address some comments from Jonathan that were missed in the merged
series. Fix line wrapping in fsdev_dax_recovery_write() and
fsdev_dax_zero_page_range() signatures.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019ecc09f607-b558c192-72fc-4c2d-9f64-3b82796e7dd4-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
Convert the WARN_ON to a fatal error when pgmap_phys > phys. This
condition means the remapped region starts after the device's data
region, which is an impossible state. Previously the probe continued
with data_offset=0, leaving virt_addr silently misaligned. Now probe
returns -EINVAL with a diagnostic message.
Fixes: 759455848df0b ("dax: Save the kva from memremap")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019ecc0999fa-97574544-8b6b-46cf-9f33-423abdbeee7f-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
Use __va(phys) instead of virt_addr + linear_offset for the kaddr
return in __fsdev_dax_direct_access(). The previous code added a
device-linear byte offset to virt_addr (which is __va of ranges[0]),
but for multi-range devices with physical gaps between ranges, this
linear arithmetic crosses the gap and produces a wrong kernel virtual
address. Using __va(phys) where phys comes from dax_pgoff_to_phys()
is correct for any range layout because the direct map translates
each physical address independently.
This leaves dev_dax->virt_addr write-only, so remove the field
(suggested by Dave Jiang).
Fixes: 759455848df0b ("dax: Save the kva from memremap")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019ecc096de8-8bc254a7-d2cc-44b6-82b1-1394fda8bb41-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
fsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and
pgmap->owner = dev_dax, but nothing ever clears them. For a dynamic
device the pgmap is devm-allocated and freed on unbind, so this is
harmless. For a static device the pgmap is the shared, long-lived one
owned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the
non-static case), and device.c's probe sets only pgmap->type, never
clearing ops/owner.
So after fsdev unbinds a static device the stale fsdev_pagemap_ops
survives on the shared pgmap. If the device is then rebound to
device_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure),
or the fsdev_dax module is unloaded, a subsequent memory_failure on that
pgmap dispatches through the stale -- and possibly freed -- handler.
Register a devm action that clears pgmap->ops and pgmap->owner on unbind,
symmetric with setting them at probe, so the pgmap carries no fsdev state
once fsdev is detached.
Suggested-by: Richard Cheng <icheng@nvidia.com>
Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax")
Signed-off-by: John Groves <john@groves.net>
Reviewed-by: Richard Cheng <icheng@nvidia.com>
Link: https://patch.msgid.link/0100019ecc094b6e-fc163bde-0396-4a33-909f-fb88e740be27-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
After the dynamic path set dev_dax->pgmap, any later probe failure left
dev_dax->pgmap dangling: devres frees the devm_kzalloc'd pgmap on probe
failure, and subsequent probe attempts would hit the "dynamic-dax with
pre-populated page map" check and fail permanently.
Factor pgmap acquisition out into fsdev_acquire_pgmap(), and defer the
dev_dax->pgmap assignment until probe can no longer fail. A failed probe
now never publishes the pointer at all, so there is nothing to unwind.
This also matches kill_dev_dax(), which already clears the dynamic pgmap
pointer on unbind: dev_dax->pgmap is now non-NULL only while the pgmap
is actually valid.
Refactor suggested by Dave Jiang.
Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019ecc092ca1-ffc7a5fd-1252-4be5-882c-fd5efdc102a9-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
Clear pgmap->vmemmap_shift for static DAX devices. When rebinding a static
device from device_dax (which may set vmemmap_shift based on alignment) to
fsdev_dax, the stale vmemmap_shift persists on the shared pgmap. Explicitly
zero it before devm_memremap_pages() so the vmemmap is built for order-0
folios as fsdev requires.
Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019ecc090eea-7c46f51e-5393-402c-850d-78059bb6d343-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
Fix memory_failure offset calculation for multi-range devices. The old
code subtracted ranges[0].range.start from the faulting PFN's physical
address, which produces an incorrect (inflated) logical offset when the
PFN falls in ranges[1] or beyond due to physical gaps between ranges.
Add fsdev_pfn_to_offset() to walk the range list and compute the correct
device-linear byte offset relative to ranges[0].start (the device data
start) -- the base the holder (xfs, famfs) maps from -- for both static
and dynamic devices.
V5 walked the pagemap's immutable pgmap->ranges[] instead, to avoid
reading the mutable dev_dax->ranges[] from this callback. That had a
different problem: it regressed static devices, where pgmap->ranges[0].start
can sit data_offset below the data start, so the reported offset came out
data_offset too high and the holder would act on the wrong blocks. For
dynamic devices the two arrays are identical, so pgmap->ranges[] only ever
helped the dynamic case while breaking the static one. Walk
dev_dax->ranges[] instead. (Richard Cheng spotted the static regression.)
Reading dev_dax->ranges[] here may race a concurrent krealloc() of the
range array via sysfs (mapping_store(), under dax_region_rwsem, which
this ->memory_failure callback does not hold). That exposure is
pre-existing -- the original single-range code read dev_dax->ranges[0]
locklessly as well -- so this patch does not make it worse; a proper fix
(locking or snapshotting) belongs in a separate change.
Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: John Groves <john@groves.net>
Reviewed-by: Richard Cheng <icheng@nvidia.com>
Link: https://patch.msgid.link/0100019ecc08d74f-ec0d09b8-11e9-4e5b-af48-8c6d382af486-000000@email.amazonses.com
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
|
|
__fsdev_dax_direct_access() returns -EFAULT without setting *kaddr when
dax_pgoff_to_phys() returns -1 (pgoff out of range). The return value
was ignored, leaving kaddr uninitialized before being passed to
fsdev_write_dax().
Check the return value and propagate the error.
Thanks to Dan Carpenter and the smatch project for reporting this.
Signed-off-by: John Groves <john@groves.net>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/0100019d8262cda2-9714d31c-8fc1-4ca5-b32d-4df678240d14-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
|
|
Add a new dax_set_ops() function that allows drivers to set the
dax_operations after the dax_device has been allocated. This is needed
for fsdev_dax where the operations need to be set during probe and
cleared during unbind.
The fsdev driver uses devm_add_action_or_reset() for cleanup consistency,
avoiding the complexity of mixing devm-managed resources with manual
cleanup in a remove() callback. This ensures cleanup happens automatically
in the correct reverse order when the device is unbound.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019d311d65a0-b9c1419e-f3a0-4afd-b0bd-848f18ff5950-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
|
|
fsdev: Add dax_operations for use by famfs.
This replicates the functionality from drivers/nvdimm/pmem.c that
conventional fs-dax file systems (e.g. xfs) use to support dax
read/write/mmap to a daxdev - without which famfs can't sit atop a
daxdev.
- These methods are based on pmem_dax_ops from drivers/nvdimm/pmem.c
- fsdev_dax_direct_access() returns the hpa, pfn and kva. The kva was
newly stored as dev_dax->virt_addr by dev_dax_probe().
- The hpa/pfn are used for mmap (dax_iomap_fault()), and the kva is used
for read/write (dax_iomap_rw())
- fsdev_dax_recovery_write() and dev_dax_zero_page_range() have not been
tested yet. I'm looking for suggestions as to how to test those.
- dax-private.h: add dev_dax->cached_size, which fsdev needs to
remember. The dev_dax size cannot change while a driver is bound
(dev_dax_resize returns -EBUSY if dev->driver is set). Caching the size
at probe time allows fsdev's direct_access path can use it without
acquiring dax_dev_rwsem (which isn't exported anyway).
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019d311d415a-bd6af0fe-5445-484c-9d39-210b8170b686-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
|
|
Save the kva from memremap because we need it for iomap rw support.
Prior to famfs, there were no iomap users of /dev/dax - so the virtual
address from memremap was not needed.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019d311d1d08-dd372cb9-5934-43b8-bef8-089660d04a81-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
|
|
The new fsdev driver provides pages/folios initialized compatibly with
fsdax - normal rather than devdax-style refcounting, and starting out
with order-0 folios.
When fsdev binds to a daxdev, it is usually (always?) switching from the
devdax mode (device.c), which pre-initializes compound folios according
to its alignment. Fsdev uses fsdev_clear_folio_state() to switch the
folios into a fsdax-compatible state.
A side effect of this is that raw mmap doesn't (can't?) work on an fsdev
dax instance. Accordingly, The fsdev driver does not provide raw mmap -
devices must be put in 'devdax' mode (drivers/dax/device.c) to get raw
mmap capability.
In this commit is just the framework, which remaps pages/folios compatibly
with fsdax.
Enabling dax changes:
- bus.h: add DAXDRV_FSDEV_TYPE driver type
- bus.c: allow DAXDRV_FSDEV_TYPE drivers to bind to daxdevs
- dax.h: prototype inode_dax(), which fsdev needs
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Suggested-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019d311cf904-419e9526-bdaf-4daa-97f1-5060b31a5c9f-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
|
John Groves