The original intent was presumably to reduce code duplication. The
trade-off was:

- No support for an NFSD proc function returning a non-success
  RPC accept_stat value.
- No support for void NFS replies to non-NULL procedures.
- Everyone pays for the deduplication with a few extra conditional
  branches in a hot path.

In addition, nfsd_dispatch() leaves *statp uninitialized in the
success path, unlike svc_generic_dispatch().

Address all of these problems by moving the logic for encoding
the NFS status code into the NFS XDR encoders themselves. Then
update the NFS .pc_func methods to return an RPC accept_stat
value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Refactor: Handle this NFS version-specific mapping in the only
place where nfserr_wrongsec is generated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Refactor: I'm about to change the return value from .pc_func. Clear
the way by replacing the RETURN_STATUS() macro with logic that
plants the status code directly into the response structure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Remove special dispatcher logic for NFSv2 error responses. These are
rare to the point of becoming extinct, but all NFS responses have to
pay the cost of the extra conditional branches.

With this change, the NFSv2 error cases now get proper
xdr_ressize_check() calls.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_release_fhandle() assumes that rqstp->rq_resp always points to
an nfsd_fhandle struct. In fact, no NFSv2 procedure uses struct
nfsd_fhandle as its response structure.

So far that has been "safe" to do because the res structs put the
resp->fh field at that same offset as struct nfsd_fhandle. I don't
think that's a guarantee, though, and there is certainly nothing
preventing a developer from altering the fields in those structures.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: These are not used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_dispatch() is a hot path. Ensure the compiler takes the
processing of rare error cases out of line.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

For consistency and code legibility, use a similar organization of
variables as svc_generic_dispatch().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Add a documenting comment for the function. Remove comments that
simply describe obvious aspects of the code, but leave comments
that explain the differences in processing of each NFS version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Reorder the arms so the compiler places checks for the most frequent
case first.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_dispatch() is a hot path. Let's optimize the XDR method calls
for the by-far common case, which is that the XDR methods are indeed
present.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: Follow-up on ten-year-old commit b9081d90 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the NFSACL code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: Follow-up on ten-year-old commit b9081d90 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the lockd code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There's no protection in nfsd_dispatch() against a NULL .pc_func
helpers. A malicious NFS client can trigger a crash by invoking the
unused/unsupported NFSv2 ROOT or WRITECACHE procedures.

The current NFSD dispatcher does not support returning a void reply
to a non-NULL procedure, so the reply to both of these is wrong, for
the moment.

Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Since only the v4 code cares about it, maybe it's better to leave
rq_lease_breaker out of the common dispatch code?
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There are actually rare races where this is possible (e.g. if a new open
intervenes between the read of i_writecount and the fi_fds).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The nfsd open code has always kept separate read-only, read-write, and
write-only opens as necessary to ensure that when a client closes or
downgrades, we don't retain more access than necessary.

Also, I didn't realize the cache behaved this way when I wrote
94415b06 "nfsd4: a client's own opens needn't prevent delegations".
There I assumed fi_fds[O_WRONLY] and fi_fds[O_RDWR] would always be
distinct.  The violation of that assumption is triggering a
WARN_ON_ONCE() and could also cause the server to give out a delegation
when it shouldn't.

Fixes: 94415b06 ("nfsd4: a client's own opens needn't prevent delegations")
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Is it just me, or is the logic written in a slightly convoluted way?

I find it a little easier to read this way.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

seq_puts is a lot cheaper than seq_printf, so use that to print
literal strings.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

silence nfscache allocation warnings with kvzalloc

Currently nfsd_reply_cache_init attempts hash table allocation through
kmalloc, and manually falls back to vzalloc if that fails. This makes
the code a little larger than needed, and creates a significant amount
of serial console spam if you have enough systems.

Switching to kvzalloc gets rid of the allocation warnings, and makes
the code a little cleaner too as a side effect.

Freeing of nn->drc_hashtbl is already done using kvfree currently.
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Fixes coccicheck warning:

fs/nfsd/nfs4proc.c:3234:5-29: WARNING: Comparison to bool
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16:    expected int status
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24:    got int status
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24:    expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24:    got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32:    expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32:    got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13:    expected restricted __be32 [usertype] err
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13:    got int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15:    expected unsigned int [assigned] [usertype] count
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15:    got restricted __be32 [usertype]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13:    expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24:    got int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13:    expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24:    got int err
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Reserving space for a large READ payload requires special handling when
reserving space in the xdr buffer pages. One problem we can have is use
of the scratch buffer, which is used to get a pointer to a contiguous
region of data up to PAGE_SIZE. When using the scratch buffer, calls to
xdr_commit_encode() shift the data to it's proper alignment in the xdr
buffer. If we've reserved several pages in a vector, then this could
potentially invalidate earlier pointers and result in incorrect READ
data being sent to the client.

I get around this by looking at the amount of space left in the current
page, and never reserve more than that for each entry in the read
vector. This lets us place data directly where it needs to go in the
buffer pages.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Now when a read delegation is given, two delegation related traces
will be printed:

    nfsd_deleg_open: client 5f45b854:e6058001 stateid 00000030:00000001
    nfsd_deleg_none: client 5f45b854:e6058001 stateid 0000002f:00000001

Although the intention is to let developers know two stateid are
returned, the traces are confusing about whether or not a read delegation
is handled out. So renaming trace_nfsd_deleg_none() to trace_nfsd_open()
and trace_nfsd_deleg_open() to trace_nfsd_deleg_read() to make
the intension clearer.

The patched traces will be:

    nfsd_deleg_read: client 5f48a967:b55b21cd stateid 00000003:00000001
    nfsd_open: client 5f48a967:b55b21cd stateid 00000002:00000001
Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This draft is an official RFC now.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It struck me while watching Jon Corbet ask how to keep kernel
Documentation up to date, that it might help if we were actually cc'd on
Documentation/filesystems/nfs/ changes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In nfsd4_encode_listxattrs(), the variable p is assigned to at one point
but this value is never used before p is reassigned. Fix this.

Addresses-Coverity: ("Unused value")
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Drop duplicate words in net/sunrpc/.
Also fix "Anyone" to be "Any one".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Missing "is".
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The delegation is no longer returnable, so I don't think there's much
point retrying the recall.

(I think it's worth asking why we even need separate CLOSED_DELEG and
REVOKED_DELEG states.  But treating them the same would currently cause
nfsd4_free_stateid to call list_del_init(&dp->dl_recall_lru) on a
delegation that the laundromat had unhashed but not revoked, incorrectly
removing it from the laundromat's reaplist or a client's dl_recall_lru.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It was an interesting idea but nobody seems to be using it, it's buggy
at this point, and nfs4state.c is already complicated enough without it.
The new nfsd/clients/ code provides some of the same functionality, and
could probably do more if desired.

This feature has been deprecated since 9d60d931 ("Deprecate nfsd
fault injection").
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pull ARM SoC fixes from Olof Johansson:
 "A collection of fixes I've been accruing over the last few weeks, none
  of them have been severe enough to warrant flushing the queue but it's
  been long enough now that it's a good idea to send them in.

  A handful of them are fixups for QSPI DT/bindings/compatibles, some
  smaller fixes for system DMA clock control and TMU interrupts on i.MX,
  a handful of fixes for OMAP, including a fix for DSI (display) on
  omap5"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (27 commits)
  arm64: dts: ns2: Fixed QSPI compatible string
  ARM: dts: BCM5301X: Fixed QSPI compatible string
  ARM: dts: NSP: Fixed QSPI compatible string
  ARM: dts: bcm: HR2: Fixed QSPI compatible string
  dt-bindings: spi: Fix spi-bcm-qspi compatible ordering
  ARM: dts: imx6sx: fix the pad QSPI1B_SCLK mux mode for uart3
  arm64: dts: imx8mp: correct sdma1 clk setting
  arm64: dts: imx8mq: Fix TMU interrupt property
  ARM: dts: imx7d-zii-rmu2: fix rgmii phy-mode for ksz9031 phy
  ARM: dts: vfxxx: Add syscon compatible with OCOTP
  ARM: dts: imx6q-logicpd: Fix broken PWM
  arm64: dts: imx: Add missing imx8mm-beacon-kit.dtb to build
  ARM: dts: imx6q-prtwd2: Remove unneeded i2c unit name
  ARM: dts: imx6qdl-gw51xx: Remove unneeded #address-cells/#size-cells
  ARM: dts: imx7ulp: Correct gpio ranges
  ARM: dts: ls1021a: fix QuadSPI-memory reg range
  arm64: defconfig: Enable ptn5150 extcon driver
  arm64: defconfig: Enable USB gadget with configfs
  ARM: configs: Update Integrator defconfig
  ARM: dts: omap5: Fix DSI base address and clocks
  ...

Pull USB/Thunderbolt fixes from Greg KH:
 "Here are some small USB and Thunderbolt driver fixes for 5.9-rc5.

  Nothing huge, just a number of bugfixes and new device ids for
  problems reported:

   - new USB serial driver ids

   - bug fixes for syzbot reported problems

   - typec driver fixes

   - thunderbolt driver fixes

   - revert of reported broken commit

  All of these have been in linux-next with no reported issues"

* tag 'usb-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: typec: intel_pmc_mux: Do not configure SBU and HSL Orientation in Alternate modes
  usb: typec: intel_pmc_mux: Do not configure Altmode HPD High
  usb: core: fix slab-out-of-bounds Read in read_descriptors
  Revert "usb: dwc3: meson-g12a: fix shared reset control use"
  usb: typec: ucsi: acpi: Check the _DEP dependencies
  usb: typec: intel_pmc_mux: Un-register the USB role switch
  usb: Fix out of sync data toggle if a configured device is reconfigured
  USB: serial: option: support dynamic Quectel USB compositions
  USB: serial: option: add support for SIM7070/SIM7080/SIM7090 modules
  thunderbolt: Use maximum USB3 link rate when reclaiming if link is not up
  thunderbolt: Disable ports that are not implemented
  USB: serial: ftdi_sio: add IDs for Xsens Mti USB converter

Pull staging/IIO driver fixes from Greg KH:
 "Here are a number of staging and IIO driver fixes for 5.9-rc5.

  The majority of these are IIO driver fixes, to resolve a timestamp
  issue that was recently found to affect a bunch of IIO drivers.

  The other fixes in here are:

   - small IIO driver fixes

   - greybus driver fix

   - counter driver fix (came in through the IIO fixes tree)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (23 commits)
  iio: adc: mcp3422: fix locking on error path
  iio: adc: mcp3422: fix locking scope
  iio: adc: meson-saradc: Use the parent device to look up the calib data
  iio:adc:max1118 Fix alignment of timestamp and data leak issues
  iio:adc:ina2xx Fix timestamp alignment issue.
  iio:adc:ti-adc084s021 Fix alignment and data leak issues.
  iio:adc:ti-adc081c Fix alignment and data leak issues
  iio:magnetometer:ak8975 Fix alignment and data leak issues.
  iio:light:ltr501 Fix timestamp alignment issue.
  iio:light:max44000 Fix timestamp alignment and prevent data leak.
  iio:chemical:ccs811: Fix timestamp alignment and prevent data leak.
  iio:proximity:mb1232: Fix timestamp alignment and prevent data leak.
  iio:accel:mma7455: Fix timestamp alignment and prevent data leak.
  iio:accel:bmc150-accel: Fix timestamp alignment and prevent data leak.
  iio:accel:mma8452: Fix timestamp alignment and prevent data leak.
  iio: accel: kxsd9: Fix alignment of local buffer.
  iio: adc: rockchip_saradc: select IIO_TRIGGERED_BUFFER
  iio: adc: ti-ads1015: fix conversion when CONFIG_PM is not set
  counter: microchip-tcb-capture: check the correct variable
  iio: cros_ec: Set Gyroscope default frequency to 25Hz
  ...

Pull driver core fixes from Greg KH:
 "Here are some small driver core and debugfs fixes for 5.9-rc5

  Included in here are:

   - firmware loader memory leak fix

   - firmware loader testing fixes for non-EFI systems

   - device link locking fixes found by lockdep

   - kobject_del() bugfix that has been affecting some callers

   - debugfs minor fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  test_firmware: Test platform fw loading on non-EFI systems
  PM: <linux/device.h>: fix @em_pd kernel-doc warning
  kobject: Drop unneeded conditional in __kobject_del()
  driver core: Fix device_pm_lock() locking for device links
  MAINTAINERS: Add the security document to SECURITY CONTACT
  driver code: print symbolic error code
  debugfs: Fix module state check condition
  kobject: Restore old behaviour of kobject_del(NULL)
  firmware_loader: fix memory leak for paged buffer

This pull request contains Broadcom ARM-based SoCs Device Tree fixes for
5.9, please pull the following:

- Florian fixes the Broadcom QSPI controller binding such that the most
  specific compatible string is the left most one, and all existing
  in-tree users are updated as well.

* tag 'arm-soc/for-5.9/devicetree-fixes' of https://github.com/Broadcom/stblinux:
  arm64: dts: ns2: Fixed QSPI compatible string
  ARM: dts: BCM5301X: Fixed QSPI compatible string
  ARM: dts: NSP: Fixed QSPI compatible string
  ARM: dts: bcm: HR2: Fixed QSPI compatible string
  dt-bindings: spi: Fix spi-bcm-qspi compatible ordering

Link: https://lore.kernel.org/r/20200909211857.4144718-1-f.fainelli@gmail.comSigned-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'imx-fixes-5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into arm/fixes

i.MX fixes for 5.9, round 2:

- Fix the misspelling of 'interrupts' property in i.MX8MQ TMU DT node.
- Correct 'ahb' clock for i.MX8MP SDMA1 in device tree.
- Fix pad QSPI1B_SCLK mux mode for UART3 on i.MX6SX.

* tag 'imx-fixes-5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
  ARM: dts: imx6sx: fix the pad QSPI1B_SCLK mux mode for uart3
  arm64: dts: imx8mp: correct sdma1 clk setting
  arm64: dts: imx8mq: Fix TMU interrupt property

Link: https://lore.kernel.org/r/20200909143844.GA25109@dragonSigned-off-by: Olof Johansson <olof@lixom.net>