- Add new flag UBC_ISMAPPED which tells ubc_uiomove() the object is mmap()ed
somewhere. Use it to decide whether to do direct-mapped copy, rather than
poking around directly in the vnode in ubc_uiomove(), which is ugly and
doesn't work for tmpfs. It would be nicer to contain all this in UVM but
the filesystem provides the needed locking here (VV_MAPPED) and to
reinvent that would suck more.
- Rename UBC_UNMAP_FLAG() to UBC_VNODE_FLAGS(). Pass in UBC_ISMAPPED where
appropriate.
VOP_RECLAIM naturally has exclusive access to the vnode, so having it
locked on entry is not strictly necessary -- but it means if there
are any final operations that must be done on the vnode, such as
ffs_update, requiring exclusive access to it, we can now kassert that
the vnode is locked in those operations.
We can't just have the caller release the last lock because some file
systems don't use genfs_lock, and require the vnode to remain valid
for VOP_UNLOCK to work, notably unionfs.
find.
The filesystem ones all call genfs_eopnotsupp - right now I am only
implementing the plumbing and we can implement fallocate and/or
fdiscard for files later.
The device ones call spec_fallocate (which is also genfs_eopnotsupp)
and spec_fdiscard, which dispatches to the device-level op.
The fifo ones all call vn_fifo_bypass, which also ends up being
EOPNOTSUPP.
the vnode operations vector for active vnodes is unsafe because it
is not known whether deadfs or the original file system will be
called.
- Pass down LK_RETRY to the lock operation (hint for deadfs only).
- Change deadfs lock operation to return ENOENT if LK_RETRY is unset.
- Change all other lock operations to check for dead vnode once
the vnode is locked and unlock and return ENOENT in this case.
With these changes in place vnode lock operations will never succeed
after vclean() has marked the vnode as VI_XLOCK and before vclean()
has changed the operations vector.
Adresses PR kern/37706 (Forced unmount of file systems is unsafe)
Discussed on tech-kern.
Welcome to 6.99.33
A type specifier of the form
enum identifier
without an enumerator list shall only appear after the type it
specifies is complete.
which means that we cannot pass an "enum vtype" argument to
kauth_access_action() without fully specifying the type first.
Unfortunately there is a complicated include file loop which
makes that difficult, so convert this minimal function into a
macro (and capitalize it).
(ok elad@)
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.
- Reorganize locking in UVM and provide extra serialisation for pmap(9).
New lock order: [vmpage-owner-lock] -> pmap-lock.
- Simplify locking in some pmap(9) modules by removing P->V locking.
- Use lock object on vmobjlock (and thus vnode_t::v_interlock) to share
the locks amongst UVM objects where necessary (tmpfs, layerfs, unionfs).
- Rewrite and optimise x86 TLB shootdown code, make it simpler and cleaner.
Add TLBSTATS option for x86 to collect statistics about TLB shootdowns.
- Unify /dev/mem et al in MI code and provide required locking (removes
kernel-lock on some ports). Also, avoid cache-aliasing issues.
Thanks to Andrew Doran and Joerg Sonnenberger, as their initial patches
formed the core changes of this branch.
in the vnode. All LK_* flags move from sys/lock.h to sys/vnode.h. Calls
to vlockmgr() in file systems get replaced with VOP_LOCK() or VOP_UNLOCK().
Welcome to 5.99.34.
Discussed on tech-kern.
years ago when the kernel was modified to not alter ABI based on
DIAGNOSTIC, and now just call the respective function interfaces
(in lowercase). Plenty of mix'n match upper/lowercase has creeped
into the tree since then. Nuke the macros and convert all callsites
to lowercase.
no functional change