knew what it was supposed to be used for and wrstuden gave a go-ahead
* while rototilling, convert file systems which went easily to
use VFS_PROTOS() instead of manually prototyping the methods
need to understand the locking around that field. Instead of setting
B_ERROR, set b_error instead. b_error is 'owned' by whoever completes
the I/O request.
need to understand the locking around that field. Instead of setting
B_ERROR, set b_error instead. b_error is 'owned' by whoever completes
the I/O request.
* panic if flushing system nodes fails: we have released too many
resources and would die anyway the next time unmount is attempted
* KASSERT that VOP_CLOSE succeeds, but always return 0. once again
we have released too many resources
XXX: maybe rewrite to be a bit more robust
- Raise an error if renaming a file to a directory.
- Raise an error if renaming a directory to a file.
- Raise an error if renaming a directory to a non-empty directory.
- Properly allow renaming a directory to an empty directory.
The system could previously crash if the kernel had DIAGNOSTIC enabled,
as this triggered a bogus assertion.
Problem found by Geoff Wing.
it has supplied us). If we fault pages which are at offset >= server
size, but less than the in-kernel vnode size, inform the file server
of the latest developments in file size before issueing the fault.
The avoids confusion with files which are not written start to finish.
fixes kern/36429 by yamt
the file server inactive less over-eagerly executed and masks some
problems with the new mounting style. Effectively, it makes some
file systems such as psshfs mountable again (only without -o allops).
fs code is a kernel buffer, pass though the length of the buffer as well.
Since the length of the userspace buffer isn'it (yet) passed through the mount
system call, add a field to the vfsops structure containing the default length.
Split sys_mount() for calls from compat code.
Ride one of the recent kernel version changes - old fs LKMs will load, but
sys_mount() will reject any attempt to use them.
1) Comply with the way buffercache(9) is intended to be used. Now we
read in single blocks of EFS_BB_SIZE, never taking in variable
length extents with a single bread() call.
2) Handle symlinks with more than one extent. There's no reason for
this to ever happen, but it's handled now.
3) Finally, add a hint to our iteration initialiser so we can start
from the desired offset, rather than naively looping through from
the beginning each time. Since we can binary search the correct
location quickly, this improves large sequential reads by about
40% with 128MB files. Improvement should increase with file size.
When reading a file, we would erroneously iterate to the next extent
before having filled the entire uio request. This lead to unnecessary
extent iteration and excessive calls to efs_read.
Sequential read performance has doubled in the uncached case and
quadrupled when data is buffered.
an init method. So get rid of it and #ifdef _LKM and just always
init in the init method. Give malloc types the same treatment.
Makes file systems nicer to work with in linksetless environments
and fixes a few LKM discrepancies.
go through VFS_ROOT() and allow to fetch it without locking it.
This allows us to call the cache flush operations also for the root
vnode and most notably fixes e.g. a "No such file or directory"
for a psshfs root directory ls -l when a file was locally deleted
and remotely re-created.
Also fix some sloppy programming in root node fetch (mostly cosmetic).
Actually, we do need separate "no references in file server" and
"noref + inactive" flags if we wish to correctly support unix open
file semantics and optimize away pre-reclaim cache flushes. So,
add PNODE_DYING which stands for norefs + inactive.
"noref + inactive" flags if we wish to correctly support unix open
file semantics and optimize away pre-reclaim cache flushes. So,
add PNODE_DYING which stands for norefs + inactive.
the kernel it has 0 references to the node in question. In other
words, this can be used to avoid inactive(), or, if the file server
does not implement inactive, prompt reclaim for removed nodes.
as we give a reference to userspace for the puffs_node for the
duration of the poll call. So reference count puffs_node separately
from the parent vnode. vref()/vrele() is not possible due to a possible
surprise visit from VOP_INACTIVE.
and other information instead of always using VDIR. To make this
possible without races, require all root node information already
in puffs_mount() and nuke puffs_start2() and the associated start
operation completely.
requested/inspired by Tobias Nygren
file system value for the size of device special files, as that
comes from specfs instead of the "host" file system. Therefore,
take care that getattr doesn't override the value of vp->v_size.
file server only if the op was still waiting for fetch (as opposed
to waiting for the response). Also, properly flag the possible
following inactive as an op for which we do not want to wait for
the response from the file server.
for nodes upon return from the userspace. Currently it can be used
to indicate that the file server should be notified of "inactive"
in case the file server has opted to not receive inactive every
time the reference count for a vnode drops to zero. (inactive is
a common event, almost never requires any action and must be executed
sychronously, so it is wasteful).
While doing this, cleanup the release-relock nonsense from the
vntouser*() arguments. It was never enabled and the whole LOCKEDVP()
concept was very broken to begin with.
all metadata info cached in the kernel while we're setattr'ing in
any case. Solves problems such as truncate (via extend-by-write)
+ chmod resulting in EPERM because the file was already read-only
when the actual truncate was flushed out of the kernel in fsync.
when unmounting the file system in case of a certain timing (and
possibly some other conditions), a thread would wait on a condition
variable, while another thread broadcast the cv and immediately
proceeded to destroy it. The result was a system frozen completely
solid shorly after the process waiting for the cv woke up. So
introduce reference counting to synchronize destruction of the
resources in unmount.
I was able to repeat the problem only on my laptop in some special
cases, so I do not know how common it was. Ironically, killing
the file server process violently instead of unmount() didn't have
this problem because it never entered the unmount path from two
directions.
it. It might be that the file server is either crashing or just
returning consistent errors. uiomove() would handle the error,
but if the pages weren't faulted in, memset() to the unfaultable
ubc window would cause a kernel page fault.
to skip unnecessary flushing when layered file system vnodes are recycled.
this also prevents a deadlock with the dodgy LFS putpages routine.
fixes the non-LFS part of PR 36150.
