Commit Graph

244 Commits

Author SHA1 Message Date
Alan Somers
8aafc8c389 [skip ci] update copyright headers in fusefs files
Sponsored by:	The FreeBSD Foundation
2019-06-28 04:18:10 +00:00
Alan Somers
c1afff113c fusefs: fix a memory leak regarding FUSE_INTERRUPT
We were leaking the fuse ticket if the original operation completed before
the daemon received the INTERRUPT operation.  Fixing this was easier than I
expected.

Sponsored by:	The FreeBSD Foundation
2019-06-27 22:24:56 +00:00
Alan Somers
435ecf40bb fusefs: recycle vnodes after their last unlink
Previously fusefs would never recycle vnodes.  After VOP_INACTIVE, they'd
linger around until unmount or the vnlru reclaimed them.  This commit
essentially actives and inlines the old reclaim_revoked sysctl, and fixes
some issues dealing with the attribute cache and multiply linked files.

Sponsored by:	The FreeBSD Foundation
2019-06-27 20:18:12 +00:00
Alan Somers
38c8634635 fusefs: counter(9) variables should not be statically initialized
Reported by:	rpokala
Sponsored by:	The FreeBSD Foundation
2019-06-27 17:59:15 +00:00
Alan Somers
560a55d094 fusefs: convert statistical sysctls to use counter(9)
counter(9) is more performant than using atomic instructions to update
sysctls that just report statistics to userland.

Sponsored by:	The FreeBSD Foundation
2019-06-27 16:30:25 +00:00
Alan Somers
caeea8b4cc fusefs: fix some memory leaks
Fix memory leaks relating to FUSE_BMAP and FUSE_CREATE.  There are still
leaks relating to FUSE_INTERRUPT, but they'll be harder to fix since the
server is legally allowed to never respond to a FUSE_INTERRUPT operation.

Sponsored by:	The FreeBSD Foundation
2019-06-27 00:00:48 +00:00
Alan Somers
f8ebf1cd7e fusefs: implement protocol 7.23's FUSE_WRITEBACK_CACHE option
As of protocol 7.23, fuse file systems can specify their cache behavior on a
per-mountpoint basis.  If they set FUSE_WRITEBACK_CACHE in
fuse_init_out.flags, then they'll get the writeback cache.  If not, then
they'll get the writethrough cache.  If they set FOPEN_DIRECT_IO in every
FUSE_OPEN response, then they'll get no cache at all.

The old vfs.fusefs.data_cache_mode sysctl is ignored for servers that use
protocol 7.23 or later.  However, it's retained for older servers,
especially for those running in jails that lack access to the new protocol.

This commit also fixes two other minor test bugs:
* WriteCluster:SetUp was using an uninitialized variable.
* Read.direct_io_pread wasn't verifying that the cache was actually
  bypassed.

Sponsored by:	The FreeBSD Foundation
2019-06-26 17:32:31 +00:00
Alan Somers
205696a17d fusefs: delete some unused mount options
The fusefs kernel module allegedly supported no_attrcache, no_readahed,
no_datacache, no_namecache, and no_mmap mount options, but the mount_fusefs
binary never did.  So there was no way to ever activate these options.
Delete them.  Some of them have alternatives:

no_attrcache: set the attr_valid time to 0 in FUSE_LOOKUP and FUSE_GETATTR
	responses.
no_readahed: set max_readahead to 0 in the FUSE_INIT response.
no_datacache: set the vfs.fusefs.data_cache_mode sysctl to 0, or (coming
	soon) set the attr_valid time to 0 and set FUSE_AUTO_INVAL_DATA in
	the FUSE_INIT response.
no_namecache: set entry_valid time to 0 in FUSE_LOOKUP and FUSE_GETATTR
	responses.

Sponsored by:	The FreeBSD Foundation
2019-06-26 15:15:24 +00:00
Alan Somers
fef464546c fusefs: implement the "time_gran" feature.
If a server supports a timestamp granularity other than 1ns, it can tell the
client this as of protocol 7.23.  The client will use that granularity when
updating its cached timestamps during write.  This way the timestamps won't
appear to change following flush.

Sponsored by:	The FreeBSD Foundation
2019-06-26 02:09:22 +00:00
Alan Somers
0a8fe2d369 fusefs: set ctime during FUSE_SETATTR following a write
As of r349396 the kernel will internally update the mtime and ctime of files
on write.  It will also flush the mtime should a SETATTR happen before the
data cache gets flushed.  Now it will flush the ctime too, if the server is
using protocol 7.23 or higher.

This is the only case in which the kernel will explicitly set a file's
ctime, since neither utimensat(2) nor any other user interfaces allow it.

Sponsored by:	The FreeBSD Foundation
2019-06-26 00:03:37 +00:00
Alan Somers
788af9538a fusefs: automatically update mtime and ctime on write
Writing should implicitly update a file's mtime and ctime.  For fuse, the
server is supposed to do that.  But the client needs to do it too, because
the FUSE_WRITE response does not include time attributes, and it's not
desirable to issue a GETATTR after every WRITE.  When using the writeback
cache, there's another hitch: the kernel should ignore the mtime and ctime
fields in any GETATTR response for files with a dirty write cache.

Sponsored by:	The FreeBSD Foundation
2019-06-25 23:40:18 +00:00
Alan Somers
0d3a88d76c fusefs: writes should update the file size, even when data_cache_mode=0
Writes that extend a file should update the file's size.  r344185 restricted
that behavior for fusefs to only happen when the data cache was enabled.
That probably made sense at the time because the attribute cache wasn't
fully baked yet.  Now that it is, we should always update the cached file
size during write.

Sponsored by:	The FreeBSD Foundation
2019-06-25 18:36:11 +00:00
Alan Somers
b9e2019755 fusefs: rewrite vop_getpages and vop_putpages
Use the standard facilities for getpages and putpages instead of bespoke
implementations that don't work well with the writeback cache.  This has
several corollaries:

* Change the way we handle short reads _again_.  vfs_bio_getpages doesn't
  provide any way to handle unexpected short reads.  Plus, I found some more
  lock-order problems.  So now when the short read is detected we'll just
  clear the vnode's attribute cache, forcing the file size to be requeried
  the next time it's needed.  VOP_GETPAGES doesn't have any way to indicate
  a short read to the "caller", so we just bzero the rest of the page
  whenever a short read happens.

* Change the way we decide when to set the FUSE_WRITE_CACHE bit.  We now set
  it for clustered writes even when the writeback cache is not in use.

Sponsored by:   The FreeBSD Foundation
2019-06-25 17:24:43 +00:00
Alan Somers
1734e205f3 fusefs: refine the short read fix from r349332
b_fsprivate1 needs to be initialized even for write operations, probably
because a buffer can be used to read, write, and read again with the final
read serviced by cache.

Sponsored by:	The FreeBSD Foundation
2019-06-24 20:08:28 +00:00
Alan Somers
17575bad85 fusefs: improve the short read fix from r349279
VOP_GETPAGES intentionally tries to read beyond EOF, so fuse_read_biobackend
can't rely on bp->b_resid > 0 indicating a short read.  And adjusting
bp->b_count after a short read seems to cause some sort of resource leak.
Instead, store the shortfall in the bp->b_fsprivate1 field.

Sponsored by:	The FreeBSD Foundation
2019-06-24 17:05:31 +00:00
Alan Somers
44f654fdc5 fusefs: fix corruption on short reads caused by r349279
Even if a short read is caused by EOF, it's still necessary to bzero the
remaining buffer, because that buffer could become valid as a result of a
future ftruncate or pwrite operation.

Reported by:	fsx
Sponsored by:	The FreeBSD Foundation
2019-06-21 23:29:29 +00:00
Alan Somers
aef22f2d75 fusefs: correctly handle short reads
A fuse server may return a short read for three reasons:

* The file is opened with FOPEN_DIRECT_IO.  In this case, the short read
  should be returned directly to userland.  We already handled this case
  correctly.

* The file was truncated server-side, and the read hit EOF.  In this case,
  the kernel should update the file size.  Fixed in the case of VOP_READ.
  Fixing this for VOP_GETPAGES is TODO.

* The file is opened in writeback mode, there are dirty buffers past what
  the server thinks is the file's EOF, and the read hit what the server
  thinks is the file's EOF.  In this case, the client is trying to read a
  hole, and should zero-fill it.  We already handled this case, and I added
  a test for it.

Sponsored by:	The FreeBSD Foundation
2019-06-21 21:44:31 +00:00
Alan Somers
87ff949a7b fusefs: raise protocol level to 7.23
None of the new features are implemented yet.  This commit just adds the new
protocol definitions and adds backwards-compatibility code for pre 7.23
servers.

Sponsored by:	The FreeBSD Foundation
2019-06-21 04:57:23 +00:00
Alan Somers
8f9b3ba718 fusefs: use standard integer types in fuse_kernel.h
This is a merge of Linux revision 4c82456eeb4da081dd63dc69e91aa6deabd29e03.
No functional change.

Sponsored by:	The FreeBSD Foundation
2019-06-21 03:17:27 +00:00
Alan Somers
b160acd1c0 fusefs: raise the protocol level to 7.21
Jumping from protocol 7.15 to 7.21 adds several new features.  While they're
all potentially useful, they're also all optional, and I'm not implementing
any right now because my highest priority lies in a later version.

Sponsored by:	The FreeBSD Foundation
2019-06-21 03:04:56 +00:00
Alan Somers
ecb489158c fusefs: diff reduction of fuse_kernel.h vs the upstream version
fuse_kernel.h is based on Linux's fuse.h.  In r349250 I modified
fuse_kernel.h by generating a diff of two versions of Linux's fuse.h and
applying it to our tree.  patch succeeded, but it put one chunk in the wrong
location.  This commit fixes that.  No functional changes.

Sponsored by:	The FreeBSD Foundation
2019-06-21 02:55:43 +00:00
Alan Somers
7cbb8e8a06 fusefs: raise protocol level to 7.15
This protocol level adds two new features: the ability for the server to
store or retrieve data into/from the client's cache.  But the messages
aren't defined soundly since they identify the file only by its inode,
without the generation number.  So it's possible for them to modify the
wrong file's cache.  Also, I don't know of any file systems in ports that
use these messages.  So I'm not implementing them.  I did add a (disabled)
test for the store message, however.

Sponsored by:	The FreeBSD Foundation
2019-06-20 23:32:25 +00:00
Alan Somers
bb23d43901 fusefs: trivially raise protocol level to 7.14
The only new feature is splice(2) support on /dev/fuse, which FreeBSD can't
support.

Sponsored by:	The FreeBSD Foundation
2019-06-20 23:12:19 +00:00
Alan Somers
192a918194 fusefs: attempt to support servers as old as protocol 7.4
Previously we allowed servers as old as 7.1 to connect (there never was a
7.0).  However, we wrongly assumed a few things about protocols older than
7.8.  This commit attempts to support servers as old as 7.4 but no older.  I
added no new tests because I'm not sure there actually _are_ any servers
this old in the wild.

Sponsored by:	The FreeBSD Foundation
2019-06-20 22:21:42 +00:00
Alan Somers
2ffddc5ee9 fusefs: raise protocol level to 7.13
This protocol version adds one new feature: the ability for the server to
set the maximum number of background requests and a "congestion threshold"
with ill-defined properties.  I don't know of any fuse file systems in ports
that use this feature, so I'm not implementing it.

Sponsored by:	The FreeBSD Foundation
2019-06-20 21:29:28 +00:00
Alan Somers
a1c9f4ad0d fusefs: implement VOP_BMAP
If the fuse daemon supports FUSE_BMAP, then use that for the block mapping.
Otherwise, use the same technique used by vop_stdbmap.  Report large values
for runp and runb in order to maximize read clustering and minimize upcalls,
even if we don't know the true layout.

The major result of this change is that sequential reads to FUSE files will
now usually happen 128KB at a time instead of 64KB.

Sponsored by:	The FreeBSD Foundation
2019-06-20 17:08:21 +00:00
Alan Somers
84879e46c2 fusefs: multiple fixes related to the write cache
* Don't always write the last page synchronously.  That's not actually
  required.  It was probably just masking another bug that I fixed later,
  possibly in r349021.

* Enable the NotifyWriteback tests now that Writeback cache is working.

* Add a test to ensure that the write cache isn't flushed synchronously when
  in writeback mode.

Sponsored by:	The FreeBSD Foundation
2019-06-17 23:34:11 +00:00
Alan Somers
402b609c80 fusefs: use cluster_read for more readahead
fusefs will now use cluster_read.  This allows readahead of more than one
cache block.  However, it won't yet actually cluster the reads because that
requires VOP_BMAP, which fusefs does not yet implement.

Sponsored by:	The FreeBSD Foundation
2019-06-17 22:01:23 +00:00
Alan Somers
d569012f45 fusefs: implement non-clustered readahead
fusefs will now read ahead at most one cache block at a time (usually 64
KB).  Clustered reads are still TODO.  Individual file systems may disable
read ahead by setting fuse_init_out.max_readahead=0 during initialization.

Sponsored by:	The FreeBSD Foundation
2019-06-17 16:56:51 +00:00
Alan Somers
b5aaf286ea fusefs: fix the "write-through" of write-through cacheing
Our fusefs(5) module supports three cache modes: uncached, write-through,
and write-back.  However, the write-through mode (which is the default) has
never actually worked as its name suggests.  Rather, it's always been more
like "write-around".  It wrote directly, bypassing the cache.  The cache
would only be populated by a subsequent read of the same data.

This commit fixes that problem.  Now the write-through mode works as one
would expect: write(2) immediately adds data to the cache and then blocks
while the daemon processes the write operation.

A side effect of this change is that non-cache-block-aligned writes will now
incur a read-modify-write cycle of the cache block.  The old behavior
(bypassing write cache entirely) can still be achieved by opening a file
with O_DIRECT.

PR:		237588
Sponsored by:	The FreeBSD Foundation
2019-06-14 19:47:48 +00:00
Alan Somers
8eecd9ce05 fusefs: enable write clustering
Enable write clustering in fusefs whenever cache mode is set to writeback
and the "async" mount option is used.  With default values for MAXPHYS,
DFLTPHYS, and the fuse max_write mount parameter, that means sequential
writes will now be written 128KB at a time instead of 64KB.

Also, add a regression test for PR 238565, a panic during unmount that
probably affects UFS, ext2, and msdosfs as well as fusefs.

PR:		238565
Sponsored by:	The FreeBSD Foundation
2019-06-14 18:14:51 +00:00
Alan Somers
dff3a6b410 fusefs: fix a bug with WriteBack cacheing
An errant vfs_bio_clrbuf snuck in in r348931.  Surprisingly, it doesn't have
any effect most of the time.  But under some circumstances it cause the
buffer to behave in a write-only fashion.

Sponsored by:	The FreeBSD Foundation
2019-06-13 19:07:03 +00:00
Alan Somers
93c0c1d4ce fusefs: fix a page fault with writeback cacheing
When truncating a file downward through a dirty buffer, it's neccessary to
update the buffer's b->dirtyend.

Sponsored by:	The FreeBSD Foundation
2019-06-11 23:46:31 +00:00
Alan Somers
a87e0831ab fusefs: WIP fixing writeback cacheing
The current "writeback" cache mode, selected by the
vfs.fusefs.data_cache_mode sysctl, doesn't do writeback cacheing at all.  It
merely goes through the motions of using buf(9), but then writes every
buffer synchronously.  This commit:

* Enables delayed writes when the sysctl is set to writeback cacheing
* Fixes a cache-coherency problem when extending a file whose last page has
  just been written.
* Removes the "sync" mount option, which had been set unconditionally.
* Adjusts some SDT probes
* Adds several new tests that mimic what fsx does but with more control and
  without a real file system.  As I discover failures with fsx, I add
  regression tests to this file.
* Adds a test that ensures we can append to a file without reading any data
  from it.

This change is still incomplete.  Clustered writing is not yet supported,
and there are frequent "panic: vm_fault_hold: fault on nofault entry" panics
that I need to fix.

Sponsored by:	The FreeBSD Foundation
2019-06-11 16:32:33 +00:00
Alan Somers
ddc51e453e fusefs: remove some stuff that was copy/pasted from nfsclient
fusefs's I/O methods were originally copy/pasted from nfsclient.  This
commit removes some irrelevant parts, like stuff involving B_NEEDCOMMIT.

Sponsored by:	The FreeBSD Foundation
2019-06-06 20:35:41 +00:00
Alan Somers
0269ae4c19 MFHead @348740
Sponsored by:	The FreeBSD Foundation
2019-06-06 16:20:50 +00:00
Alan Somers
011bca9948 fusefs: simplify fuse_write_biobackend. No functional change.
Sponsored by:	The FreeBSD Foundation
2019-06-05 20:18:56 +00:00
Alan Somers
a639731ba9 fusefs: respect RLIMIT_FSIZE
Sponsored by:	The FreeBSD Foundation
2019-06-03 23:24:07 +00:00
Alan Somers
6ff7f297f8 fusefs: don't require FUSE_EXPORT_SUPPORT for async invalidation
In r348560 I thought that FUSE_EXPORT_SUPPORT was required for cases where
the node to be invalidated (or the parent of the entry to be invalidated)
wasn't cached.  But I realize now that that's not the case.  During entry
invalidation, if the parent isn't in the vfs hash table, then it must've
been reclaimed.  And since fuse_vnop_reclaim does a cache_purge, that means
the entry to be invalidated has already been removed from the namecache.
And during inode invalidation, if the inode to be invalidated isn't in the
vfs hash table, then it too must've been reclaimed.  In that case it will
have no buffer cache to invalidate.

Sponsored by:	The FreeBSD Foundation
2019-06-03 20:45:32 +00:00
Alan Somers
eae1ae132c fusefs: support asynchronous cache invalidation
Protocol 7.12 adds a way for the server to notify the client that it should
invalidate an inode's data cache and/or attributes.  This commit implements
that mechanism.  Unlike Linux's implementation, ours requires that the file
system also supports FUSE_EXPORT_SUPPORT (NFS-style lookups).  Otherwise the
invalidation operation will return EINVAL.

Sponsored by:	The FreeBSD Foundation
2019-06-03 17:34:01 +00:00
Alan Somers
c2d70d6e6f fusefs: support name cache invalidation
Protocol 7.12 adds a way for the server to notify the client that it should
invalidate an entry from its name cache.  This commit implements that
mechanism.

Sponsored by:	The FreeBSD Foundation
2019-06-01 00:11:19 +00:00
Alan Somers
0d2bf48996 fusefs: check the vnode cache when looking up files for the NFS server
FUSE allows entries to be cached for a limited amount of time.  fusefs's
vnop_lookup method already implements that using the timeout functionality
of cache_lookup/cache_enter_time.  However, lookups for the NFS server go
through a separate path: vfs_vget.  That path can't use the same timeout
functionality because cache_lookup/cache_enter_time only work on pathnames,
whereas vfs_vget works by inode number.

This commit adds entry timeout information to the fuse vnode structure, and
checks it during vfs_vget.  This allows the NFS server to take advantage of
cached entries.  It's also the same path that FUSE's asynchronous cache
invalidation operations will use.

Sponsored by:	The FreeBSD Foundation
2019-05-31 21:22:58 +00:00
Alan Somers
a4856c96d0 fusefs: raise protocol level to 7.12
This commit raises the protocol level and adds backwards-compatibility code
to handle structure size changes.  It doesn't implement any new features.
The new features added in protocol 7.12 are:

* server-side umask processing (which FreeBSD won't do)
* asynchronous inode and directory entry invalidation (which I'll do next)

Sponsored by:	The FreeBSD Foundation
2019-05-29 16:39:52 +00:00
Alan Somers
e039bafa87 fusefs: add comments explaining why 7.11 features aren't implemented
Protocol 7.11 adds two new features, but neither of them were defined
correctly.  FUSE_IOCTL messages don't work for 32-bit daemons on a 64-bit
host (fixed in protocol 7.16).  FUSE_POLL is basically unusable until 7.21.
Before 7.21, the client can't choose which events to register for; the
client registers for "something" and the server replies to say which events
the client is registered for.  Also, before 7.21 there was no way for a
client to deregister a file handle.

Sponsored by:	The FreeBSD Foundation
2019-05-29 02:03:08 +00:00
Alan Somers
9c62bc7045 fusefs: raise protocol level to 7.11
This commit adds the definitions for protocol 7.11 but doesn't yet implement
the new features.  The new features are optional, so they can come later.

Sponsored by:	The FreeBSD Foundation
2019-05-29 00:54:49 +00:00
Alan Somers
3f105d16a0 fusefs: raise protocol level to 7.10
Protocol version 7.10 has only one new feature, and I'm choosing not to
implement it, so this commit is basically a noop.  The sole new feature is
the FOPEN_NONSEEKABLE flag, which a fuse file system can return to indicate
that a certain file handle cannot be seeked.  However, I'm unaware of any
file system in ports that uses this flag.

Sponsored by:	The FreeBSD Foundation
2019-05-29 00:01:36 +00:00
Alan Somers
d4fd0c8148 fusefs: set the flags fields of fuse_write_in and fuse_read_in
These fields are supposed to contain the file descriptor flags as supplied
to open(2) or set by fcntl(2).  The feature is kindof useless on FreeBSD
since we don't supply all of these flags to fuse (because of the weak
relationship between struct file and struct vnode).  But we should at least
set the access mode flags (O_RDONLY, etc).

This is the last fusefs change needed to get full protocol 7.9 support.
There are still a few options we don't support for good reason (mandatory
file locking is dumb, flock support is broken in the protocol until 7.17,
etc), but there's nothing else to do at this protocol level.

Sponsored by:	The FreeBSD Foundation
2019-05-28 01:09:19 +00:00
Alan Somers
8aa24ed381 fusefs: flock(2) locks must be implemented in-kernel
If a FUSE file system sets the FUSE_POSIX_LOCKS flag then it can support
fcntl(2)-style locks directly.  However, the protocol does not adequately
support flock(2)-style locks until revision 7.17.  They must be implemented
locally in-kernel instead.  This unfortunately breaks the interoperability
of fcntl(2) and flock(2) locks for file systems that support the former.
C'est la vie.

Prior to this commit flock(2) would get sent to the server as a
fcntl(2)-style lock with the lock owner field set to stack garbage.

Sponsored by:	The FreeBSD Foundation
2019-05-28 00:03:46 +00:00
Alan Somers
9bcecf0fd7 fusefs: clear fuse_getattr_in.getattr_flags
Protocol 7.9 adds this field.  We could use it to store the file handle of
the file whose attributes we're requesting.  However, that requires extra
work at runtime to look up a file handle, and I'm not aware of any file
systems that care.  So it's easiest just to clear it.

Sponsored by:	The FreeBSD Foundation
2019-05-27 22:25:39 +00:00
Alan Somers
bda39894c5 fusefs: set FUSE_WRITE_CACHE when writing from cache
This bit tells the server that we're not sure which uid, gid, and/or pid
originated the write.  I don't know of a single file system that cares, but
it's part of the protocol.

Sponsored by:	The FreeBSD Foundation
2019-05-27 21:36:28 +00:00