Commit Graph

137301 Commits

Author SHA1 Message Date
Kristof Provost
b62489cc92 pf: Support killing floating states by interface
Floating states get assigned to interface 'all' (V_pfi_all), so when we
try to flush all states for an interface states originally created
through this interface are not flushed. Only if-bound states can be
flushed in this way.

Given that we track the original interface we can check if the state's
interface is 'all', and if so compare to the orig_if instead.

MFC after:	1 week
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30246
2021-05-20 12:49:27 +02:00
Kristof Provost
d0fdf2b28f pf: Track the original kif for floating states
Track (and display) the interface that created a state, even if it's a
floating state (and thus uses virtual interface 'all').

MFC after:	1 week
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30245
2021-05-20 12:49:27 +02:00
Kristof Provost
0592a4c83d pf: Add DIOCGETSTATESNV
Add DIOCGETSTATESNV, an nvlist-based alternative to DIOCGETSTATES.

MFC after:      1 week
Sponsored by:   Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30243
2021-05-20 12:49:27 +02:00
Kristof Provost
1732afaa0d pf: Add DIOCGETSTATENV
Add DIOCGETSTATENV, an nvlist-based alternative to DIOCGETSTATE.

MFC after:	1 week
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30242
2021-05-20 12:49:26 +02:00
Wojciech Macek
787845c0e8 Revert "ip_mroute: refactor bw_meter API"
This reverts commit d1cd99b147.
2021-05-20 12:14:58 +02:00
Marcin Wojtas
240429103c Rename ofwpci.c to ofw_pcib.c
It's a class0 driver that implements some pcib methods and creates
a pci bus as its children.
The "ofw_pci" name will be used by a new driver that will be a subclass
of the pci bus.
No functional changes intended.

Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: andrew
Obtained from: Semihalf
Sponsored by: Alstom Group
Differential Revision: https://reviews.freebsd.org/D30226
2021-05-20 11:22:25 +02:00
Marcin Wojtas
b08bf4c35c sdhci_fsl_fdt: Skip vccq reconfiguration without regulator
There is no need to preform any voltage reconfiguration
in case the vccq regulator is not physically attached to the
slot.

Submitted by: Lukasz Hajec <lha@semihalf.com>
Obtained from: Semihalf
Sponsored by: Alstom Group
Differential Revision: https://reviews.freebsd.org/D30355
2021-05-20 11:21:53 +02:00
Ceri Davies
c1a148873d sys/*/conf/*, docs: fix links to handbook
While here, fix all links to older en_US.ISO8859-1 documentation
in the src/ tree.

PR:             255026
Reported by:    Michael Büker <freebsd@michael-bueker.de>
Reviewed by:    dbaio
Approved by:    blackend (mentor), re (gjb)
MFC after:      10 days
Differential Revision: https://reviews.freebsd.org/D30265
2021-05-20 09:27:10 +01:00
Wojciech Macek
d1cd99b147 ip_mroute: refactor bw_meter API
API should work as following:
- periodicaly report Lower-or-EQual bandwidth (LEQ) connections
  over kernel socket, if user application registered for such
  per-flow notifications
- report Grater-or-EQual (GEQ) bandwidth as soon as it reaches
  specified value in configured time window

Custom implementation of callouts was removed. There is no
point of doing calout-wheel here as generic callouts are
doing exactly the same. The performance is not critical
for such reporting, so the biggest concern should be
to have a code which can be easily maintained.

This is ia preparation for locking rework which is highly inefficient.

Approved by:    mw
Sponsored by:   Stormshield
Obtained from:  Semihalf
Differential Revision:  https://reviews.freebsd.org/D30210
2021-05-20 10:13:55 +02:00
John Baldwin
3bede2908a cxgbei: Add tunable sysctls for the FirstBurstLength and MaxBurstLength.
Reviewed by:	np
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D30269
2021-05-19 15:56:54 -07:00
John Baldwin
671fd0ec8d cxgbei: Remove unused sysctls.
These were seemingly copied over from icl_soft.

Reviewed by:	np
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D30268
2021-05-19 15:56:45 -07:00
John Baldwin
a9f0cf4838 cxgbe: Fix some merge-o's for the per-rxq iSCSI counters.
I botched a few of the changes when rebasing the changes in
4b6ed0758d across the changes in
43bbae1948.

- Move the counter allocations into alloc_ofld_rxq().

- Free the counters freeing an ofld rxq.

Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D30267
2021-05-19 15:56:31 -07:00
Konstantin Belousov
77b637338a alc(4): add support for Mikrotik 10/25G NIC
The new Mikrotik 10/25G NIC is mostly compatible with AR8151 hardware,
with few exceptions:

* card supports only 32bit DMA operations
* card does not support write-one-to-clear semantics for interrupt status
  register
* MDIO operations can take longer to complete

This patch adds support for Mikrotik 10/25G NIC to the alc driver
while maintaining support for all earlier HW.

The patch was tested with FreeBSD main branch as of commit
f4b38c360e

This was tested on Intel i7-4790K system with Mikrotik 10/25G NIC.
This was tested on Intel i7-4790K system with RB44Ge (AR8151 based 4-port NIC)
to verify backwards compatibility.

PR:	256000
Submitted by:	 Gatis Peisenieks  <gatis@mikrotik.com>
MFC after:	1 week
2021-05-20 01:30:25 +03:00
Warner Losh
96480d9b33 cam_sim: add doxygen to cam_sim_alloc_dev
cam_sim_alloc_dev was overlooked when cam_sim_alloc was documented.
Add doxygen docs for it, pointing at cam_sim_alloc.

Sponsored by:		Netflix
2021-05-19 15:59:09 -06:00
Rick Macklem
c28cb257dd nfscl: Fix NFSv4.1/4.2 mount recovery from an expired lease
The most difficult NFSv4 client recovery case happens when the
lease has expired on the server.  For NFSv4.0, the client will
receive a NFSERR_EXPIRED reply from the server to indicate this
has happened.
For NFSv4.1/4.2, most RPCs have a Sequence operation and, as such,
the client will receive a NFSERR_BADSESSION reply when the lease
has expired for these RPCs.  The client will then call nfscl_recover()
to handle the NFSERR_BADSESSION reply.  However, for the expired lease
case, the first reclaim Open will fail with NFSERR_NOGRACE.

This patch recognizes this case and calls nfscl_expireclient()
to handle the recovery from an expired lease.

This patch only affects NFSv4.1/4.2 mounts when the lease
expires on the server, due to a network partitioning that
exceeds the lease duration or similar.

MFC after:	2 weeks
2021-05-19 14:52:56 -07:00
Mateusz Guzik
4fe925b81e fdescfs: allow shared locking of root vnode
Eliminates fdescfs from lock profile when running poudriere.
2021-05-19 17:58:54 +00:00
Mateusz Guzik
43999a5cba pseudofs: use vget_prep + vget_finish instead of vget + the interlock 2021-05-19 17:58:42 +00:00
Alexander Motin
4a6830761c Fix packet cbs/ebs conversion.
Each packet is counted as 128 bytes by the code, not 125.  Not sure
what I was thinking about here 14 years ago.  May be just a typo.

Reported by:	Dmitry Luhtionov <dmitryluhtionov@gmail.com>
MFC after:	2 weeks
2021-05-19 11:04:08 -04:00
Bjoern A. Zeeb
f0a5e81af4 arm64: rockchip, implement the two rk805/808 clocks
While the xin32k clk was implemented in rk3399_cru as a fixed rate
clock, migrate it to rk805 as we will also need the 2nd clock
'rtc_clko_wifi' for SDIO and BT.
Both clocks remain fixed rate, and while the 1st one is always on
(though that is not expressed in the clk framework), the 2nd one
we can toggle on/off.

Reviewed-by:	manu
Tested-by:	manu
MFC-after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D26870
2021-05-19 11:48:11 +00:00
Navdeep Parhar
3965469eaa cxgbe(4): Remove some dead code.
MFC after:	3 days
2021-05-18 23:16:03 -07:00
Rick Macklem
fc0dc94029 nfsd: Reduce the callback timeout to 800msec
Recent discussion on the nfsv4@ietf.org mailing list confirmed
that an NFSv4 server should reply to an RPC in less than 1second.
If an NFSv4 RPC requires a delegation be recalled,
the server will attempt a CB_RECALL callback.
If the client is not responsive, the RPC reply will be delayed
until the callback times out.
Without this patch, the timeout is set to 4 seconds (set in
ticks, but used as seconds), resulting in the RPC reply taking over 4sec.
This patch redefines the constant as being in milliseconds and it
implements that for a value of 800msec, to ensure the RPC
reply is sent in less than 1second.

This patch only affects mounts from clients when delegations
are enabled on the server and the client is unresponsive to callbacks.

MFC after:	2 weeks
2021-05-18 16:17:58 -07:00
Rick Macklem
b3d4c70dc6 nfsd: Add support for CLAIM_DELEG_CUR_FH to the NFSv4.1/4.2 Open
The Linux NFSv4.1/4.2 client now uses the CLAIM_DELEG_CUR_FH
variant of the Open operation when delegations are recalled and
the client has a local open of the file.  This patch adds
support for this variant of Open to the NFSv4.1/4.2 server.

This patch only affects mounts from Linux clients when delegations
are enabled on the server.

MFC after:	2 weeks
2021-05-18 15:53:54 -07:00
Zhenlei Huang
3d846e4822 Do not forward datagrams originated by link-local addresses
The current implement of ip_input() reject packets destined for
169.254.0.0/16, but not those original from 169.254.0.0/16 link-local
addresses.

Fix to fully respect RFC 3927 section 2.7.

PR:		255388
Reviewed by:	donner, rgrimes, karels
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D29968
2021-05-18 22:59:46 +02:00
Markus Stoff
63b6a08ce2 ng_parse: IP address parsing in netgraph eating too many characters
Once the final component of the IP address has been parsed, the offset
on the input must not be advanced, as this would remove an unparsed
character from the input.

Submitted by:	Markus Stoff
Reviewed by:	donner
MFC after:	3 weeks
Differential Revision: https://reviews.freebsd.org/D26489
2021-05-18 22:36:28 +02:00
Lv Yunlong
b295c5ddce socket: Release cred reference later in sodealloc()
We dereference so->so_cred to update the per-uid socket buffer
accounting, so the crfree() call must be deferred until after that
point.

PR:		255869
MFC after:	1 week
2021-05-18 15:25:40 -04:00
Mark Johnston
c4a6258d70 dummynet: Fix mbuf tag allocation failure handling
PR:		255875, 255878, 255879, 255880
Reviewed by:	donner, kp
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D30318
2021-05-18 15:25:16 -04:00
Konstantin Belousov
8cf912b017 ttydev_write: prevent stops while terminal is busied
Since busy state is checked by all blocked writes, stopping a process
which waits in ttydisc_write() causes cascade.  Utilize sigdeferstop()
to avoid the issue.

Submitted by:	Jakub Piecuch <j.piecuch96@gmail.com>
PR:	255816
MFC after:	1 week
2021-05-18 20:52:03 +03:00
Mateusz Guzik
cc6f46ac2f vfs: refactor vdrop
In particular move vunlazy into its own routine.
2021-05-18 15:30:28 +00:00
Mateusz Guzik
715fcc0d34 vfs: change vn_freevnodes_* prefix to idiomatic vfs_freevnodes_* 2021-05-18 15:30:28 +00:00
Hans Petter Selasky
e5ff940a81 Propagate down USB explore error codes, so that failures to enumerate USB HUBs
behind USB HUBs are detected and the USB reset counter logic will kick in
preventing enumeration of continuously failing ports.

Submitted by:	phk@
Tested by:	bz@
PR:		237666
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking
2021-05-18 16:11:35 +02:00
Hans Petter Selasky
70ffaaa69c Update USB_PORT_RESET_RECOVERY to comply with the USB 2.0 specification which
says it should be max 10 milliseconds.

This may fix some USB enumeration issues:
> usbd_req_re_enumerate: addr=3, set address failed! (USB_ERR_IOERROR, ignored)
> usbd_setup_device_desc: getting device descriptor at addr 3 failed,

Found by:	Zhichao1.Li@dell.com
MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking
2021-05-18 15:52:41 +02:00
Hans Petter Selasky
00e501d720 Update usb_timings_sysctl_handler() to accept any value for timings between
0 milliseconds and 2 seconds inclusivly. Some style fixes while at it.

The USB specification has minimum values and maximum values,
and not only minimum values.

MFC after:	1 week
Sponsored by:	Mellanox Technologies // NVIDIA Networking
2021-05-18 15:52:41 +02:00
Roger Pau Monné
9e14ac116e x86/xen: further PVHv1 removal cleanup
The AP startup extern variable declarations are not longer needed,
since PVHv2 uses the native AP startup path using the lapic. Remove
the declaration and make the variables static to mp_machdep.c

Sponsored by: Citrix Systems R&D
2021-05-18 10:43:31 +02:00
Colin Percival
b6be9566d2 Fix buffer overflow in preloaded hostuuid cleaning
When a module of type "hostuuid" is provided by the loader,
prison0_init strips any trailing whitespace and ASCII control
characters by (a) adjusting the buffer length, and (b) zeroing out
the characters in question, before storing it as the system's
hostuuid.

The buffer length adjustment was correct, but the zeroing overwrote
one byte higher in memory than intended -- in the typical case,
zeroing one byte past the end of the hostuuid buffer.  Due to the
layout of buffers passed by the boot loader to the kernel, this will
be the first byte of a subsequent buffer.

This was *probably* harmless; prison0_init runs after preloaded kernel
modules have been linked and after the preloaded /boot/entropy cache
has been processed, so in both cases having the first byte overwritten
will not cause problems.  We cannot however rule out the possibility
that other objects which are preloaded by the loader could suffer from
having the first byte overwritten.

Since the zeroing does not in fact serve any purpose, remove it and
trim trailing whitespace and ASCII control characters by adjusting
the buffer length alone.

Fixes:		c3188289 Preload hostuuid for early-boot use
Reviewed by:	kevans, markj
MFC after:	3 days
2021-05-17 20:07:49 -07:00
Colin Percival
330f110bf1 Fix 'hostuuid: preload data malformed' warning
If the preloaded hostuuid value is invalid and verbose booting is
enabled, a warning is printed.  This printf had two bugs:

1. It was missing a trailing \n character.
2. The malformed UUID is printed with %s even though it is not known
to be NUL-terminated.

This commit adds the missing \n and uses %.*s with the (already known)
length of the preloaded UUID to ensure that we don't read past the end
of the buffer.

Reported by:	kevans
Fixes:		c3188289 Preload hostuuid for early-boot use
MFC after:	3 days
2021-05-17 20:07:49 -07:00
John Baldwin
8d2b4b2e7c cxgbe: Cast pointer arguments to trunc_page() to vm_offset_t.
Reported by:	mjg, jenkins, rmacklem
Fixes:		46bee8043e
Sponsored by:	Chelsio Communications
2021-05-17 17:04:22 -07:00
Mark Johnston
4224dbf4c7 xen: Remove leftover bits missed in commit ac3ede5371
Fixes:		ac3ede5371 ("x86/xen: remove PVHv1 code")
Reviewed by:	royger
Differential Revision:	https://reviews.freebsd.org/D30316
2021-05-17 13:06:44 -04:00
Kristof Provost
02c44f40f9 dummynet: Remove unused code
We never set 'busy' and never dequeue from the pending mq. Remove this
code.

Reviewed by:	ae
MFC after:	1 week
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30313
2021-05-17 15:03:55 +02:00
Kristof Provost
d69cc04014 pf: Set the pfik_group for userspace
Userspace relies on this pointer to work out if the kif is a group or
not. It can't use it for anything else, because it's a pointer to a
kernel address. Substitute 0xfeedc0de for 'true', so that we don't leak
kernel memory addresses to userspace.

PR:		255852
Reviewed by:	donner
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D30284
2021-05-17 13:48:06 +02:00
Justin Hibbits
b2ee069e8c Fix locking in qoriq_gpio
qoriq_gpio_pin_setflags() locks the device mutex, as does
qoriq_gpio_map_gpios(), causing a recursion on non-recursive lock.  This
was missed during testing for 16e549ebe.
2021-05-17 08:46:45 -05:00
Justin Hibbits
ffd21bd289 Make ISA_206_ATOMICS a kernel option
Summary:
To make it easier to build a kernel with PowerISA 2.06 atomics (sub-word
atomics), add a kernel config option.  User space still needs to specify
it as a CFLAG but that seems easier to do than for the kernel config.

Reviewed By: luporl
Differential Revision: https://reviews.freebsd.org/D29809
2021-05-17 08:46:38 -05:00
Justin Hibbits
7ed09a6778 powerpc: Rework IPI message processing
Summary:
There's no need to use a while loop in the IPI handler, the message list
is cached once and processed.  Instead, since the existing code calls
ffs(), sort the handlers, and use a simple 'if' sequence.

Reviewed By: nwhitehorn
Differential Revision: https://reviews.freebsd.org/D30018
2021-05-17 08:26:40 -05:00
Justin Hibbits
9aad27931e powerpc64/radix mmu: Remove dead variable
Remove dead variable from mmu_radix_extract_and_hold().  Based on
r352408 for amd64.
2021-05-17 08:26:39 -05:00
Roger Pau Monné
ac3ede5371 x86/xen: remove PVHv1 code
PVHv1 was officially removed from Xen in 4.9, so just axe the related
code from FreeBSD.

Note FreeBSD supports PVHv2, which is the replacement for PVHv1.

Sponsored by: Citrix Systems R&D
Reviewed by: kib, Elliott Mitchell
Differential Revision: https://reviews.freebsd.org/D30228
2021-05-17 11:41:21 +02:00
Mitchell Horne
2117a66af5 xen: remove hypervisor_info
This was a source of indirection needed to support PVHv1. Now that that
support has been removed, we can eliminate it.

Reviewed by: royger
2021-05-17 10:56:52 +02:00
Mitchell Horne
c93e6ea344 xen: remove support for PVHv1 bootpath
PVHv1 is a legacy interface supported only by Xen versions 4.4 through
4.9.

Reviewed by: royger
2021-05-17 10:56:52 +02:00
Mark Johnston
60cb98a1bd linux: Fix a mistake in commit fb58045145
The change to futex_andl_smap() should have ordered stac before the
load from a user address, otherwise it does not fix anything.

Fixes:	fb58045145 ("linux: Fix SMAP-enabled futex routines")
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2021-05-16 22:23:14 -04:00
Mark Johnston
5b81e2e1bc virtio_scsi: Zero stack-allocated CCBs
Fixes:	3394d4239b ("cam: allocate CCBs from UMA for SCSI and ATA IO")
Reported by:	syzbot+2e9ce63919709feb3d1c@syzkaller.appspotmail.com
Reviewed by:	trasz
Sponsored by:	The FreeBSD Foundation
2021-05-16 22:20:39 -04:00
Kirk McKusick
9a2fac6ba6 Fix handling of embedded symbolic links (and history lesson).
The original filesystem release (4.2BSD) had no embedded sysmlinks.
Historically symbolic links were just a different type of file, so
the content of the symbolic link was contained in a single disk block
fragment. We observed that most symbolic links were short enough that
they could fit in the area of the inode that normally holds the block
pointers. So we created embedded symlinks where the content of the
link was held in the inode's pointer area thus avoiding the need to
seek and read a data fragment and reducing the pressure on the block
cache. At the time we had only UFS1 with 32-bit block pointers,
so the test for a fastlink was:

	di_size < (NDADDR + NIADDR) * sizeof(daddr_t)

(where daddr_t would be ufs1_daddr_t today).

When embedded symlinks were added, a spare field in the superblock
with a known zero value became fs_maxsymlinklen. New filesystems
set this field to (NDADDR + NIADDR) * sizeof(daddr_t). Embedded
symlinks were assumed when di_size < fs->fs_maxsymlinklen. Thus
filesystems that preceeded this change always read from blocks
(since fs->fs_maxsymlinklen == 0) and newer ones used embedded
symlinks if they fit. Similarly symlinks created on pre-embedded
symlink filesystems always spill into blocks while newer ones will
embed if they fit.

At the same time that the embedded symbolic links were added, the
on-disk directory structure was changed splitting the former
u_int16_t d_namlen into u_int8_t d_type and u_int8_t d_namlen.
Thus fs_maxsymlinklen <= 0 (as used by the OFSFMT() macro) can
be used to distinguish old directory formats. In retrospect that
should have just been an added flag, but we did not realize we
needed to know about that change until it was already in production.

Code was split into ufs/ffs so that the log structured filesystem could
use ufs functionality while doing its own disk layout. This meant
that no ffs superblock fields could be used in the ufs code. Thus
ffs superblock fields that were needed in ufs code had to be copied
to fields in the mount structure. Since ufs_readlink needed to know
if a link was embedded, fs_maxlinklen gets copied to mnt_maxsymlinklen.

The kernel panic that arose to making this fix was triggered when a
disk error created an inode of type symlink with no allocated data
blocks but a large size. When readlink was called the uiomove was
attempted which segment faulted.

static int
ufs_readlink(ap)
	struct vop_readlink_args /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
	} */ *ap;
{
	struct vnode *vp = ap->a_vp;
	struct inode *ip = VTOI(vp);
	doff_t isize;

	isize = ip->i_size;
	if ((isize < vp->v_mount->mnt_maxsymlinklen) ||
	    DIP(ip, i_blocks) == 0) { /* XXX - for old fastlink support */
		return (uiomove(SHORTLINK(ip), isize, ap->a_uio));
	}
	return (VOP_READ(vp, ap->a_uio, 0, ap->a_cred));
}

The second part of the "if" statement that adds

	DIP(ip, i_blocks) == 0) { /* XXX - for old fastlink support */

is problematic. It never appeared in BSD released by Berkeley because
as noted above mnt_maxsymlinklen is 0 for old format filesystems, so
will always fall through to the VOP_READ as it should. I had to dig
back through `git blame' to find that Rodney Grimes added it as
part of ``The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch.''
He must have brought it across from an earlier FreeBSD. Unfortunately
the source-control logs for FreeBSD up to the merger with the
AT&T-blessed 4.4BSD-Lite conversion were destroyed as part of the
agreement to let FreeBSD remain unencumbered, so I cannot pin-point
where that line got added on the FreeBSD side.

The one change needed here is that mnt_maxsymlinklen is declared as
an `int' and should be changed to be `u_int64_t'.

This discovery led us to check out the code that deletes symbolic
links. Specifically

	if (vp->v_type == VLNK &&
	    (ip->i_size < vp->v_mount->mnt_maxsymlinklen ||
	     datablocks == 0)) {
		if (length != 0)
			panic("ffs_truncate: partial truncate of symlink");
		bzero(SHORTLINK(ip), (u_int)ip->i_size);
		ip->i_size = 0;
		DIP_SET(ip, i_size, 0);
		UFS_INODE_SET_FLAG(ip, IN_SIZEMOD | IN_CHANGE | IN_UPDATE);
		if (needextclean)
			goto extclean;
		return (ffs_update(vp, waitforupdate));
	}

Here too our broken symlink inode with no data blocks allocated
and a large size will segment fault as we are incorrectly using the
test that we have no data blocks to decide that it is an embdedded
symbolic link and attempting to bzero past the end of the inode.
The test for datablocks == 0 is unnecessary as the test for
ip->i_size < vp->v_mount->mnt_maxsymlinklen will do the right
thing in all cases.

The test for datablocks == 0 was added by David Greenman in this commit:

Author: David Greenman <dg@FreeBSD.org>
Date:   Tue Aug 2 13:51:05 1994 +0000

    Completed (hopefully) the kernel support for old style "fastlinks".

    Notes:
	svn path=/head/; revision=1821

I am guessing that he likely earlier added the incorrect test in the
ufs_readlink code.

I asked David if he had any recollection of why he made this change.
Amazingly, he still had a recollection of why he had made a one-line
change more than twenty years ago. And unsurpisingly it was because
he had been stuck between a rock and a hard place.

FreeBSD was up to 1.1.5 before the switch to the 4.4BSD-Lite code
base. Prior to that, there were three years of development in all
areas of the kernel, including the filesystem code, from the combined
set of people including Bill Jolitz, Patchkit contributors, and
FreeBSD Project members. The compatibility issue at hand was caused
by the FASTLINKS patches from Curt Mayer. In merging in the 4.4BSD-Lite
changes David had to find a way to provide compatibility with both
the changes that had been made in FreeBSD 1.1.5 and with 4.4BSD-Lite.
He felt that these changes would provide compatibility with both systems.

In his words:
``My recollection is that the 'FASTLINKS' symlinks support in
FreeBSD-1.x, as implemented by Curt Mayer, worked differently than
4.4BSD. He used a spare field in the inode to duplicately store the
length. When the 4.4BSD-Lite merge was done, the optimized symlinks
support for existing filesystems (those that were initialized in
FreeBSD-1.x) were broken due to the FFS on-disk structure of
4.4BSD-Lite differing from FreeBSD-1.x. My commit was needed to
restore the backward compatibility with FreeBSD-1.x filesystems.
I think it was the best that could be done in the somewhat urgent
circumstances of the post Berkeley-USL settlement. Also, regarding
Rod's massive commit with little explanation, some context: John
Dyson and I did the initial re-port of the 4.4BSD-Lite kernel to
the 386 platform in just 10 days. It was by far the most intense
hacking effort of my life. In addition to the porting of tons of
FreeBSD-1 code, I think we wrote more than 30,000 lines of new code
in that time to deal with the missing pieces and architectural
changes of 4.4BSD-Lite. We didn't make many notes along the way.
There was a lot of pressure to get something out to the rest of the
developer community as fast as possible, so detailed discrete commits
didn't happen - it all came as a giant wad, which is why Rod's
commit message was worded the way it was.''

Reported by:  Chuck Silvers
Tested by:    Chuck Silvers
History by:   David Greenman Lawrence
MFC after:    1 week
Sponsored by: Netflix
2021-05-16 17:04:11 -07:00
Rick Macklem
46269d66ed NFSv4 server: Re-establish the delegation recall timeout
Commit 7a606f280a allowed the server to do retries of CB_RECALL
callbacks every couple of seconds.  This was needed to allow the
Linux client to re-establish the back channel.
However this patch broke the delegation timeout check, such that
it would just keep retrying CB_RECALLS.
If the client has crashed or been network patitioned from the
server, this continues until the client TCP reconnects to
the server and re-establishes the back channel.

This patch modifies the code such that it still times out the
delegation recall after some minutes, so that the server will
allow the conflicting client request once the delegation times out.

This patch only affects the NFSv4 server when delegations are
enabled and a NFSv4 client that holds a delegation has crashed
or been network partitioned from the server for at least several
minutes when a delegation needs to be recalled.

MFC after:	2 weeks
2021-05-16 16:40:01 -07:00