mprotect settings so that debuggers can write to the text segment of traced
processes so that they can insert breakpoints. Turned off by default.
Ok: chuq (for now)
KASSERT() that we don't.
When calculating the load address for the interpreter (e.g. ld.elf_so),
we need to take into account wether the exec'd process will run with
topdown memory or bottom up. We can not use the current vmspace's flags
to test for that, as this happens too early. Luckily the execpack already
knows what the new state will be later, so instead of testing the current
vmspace, pass the info as additional argument to struct emul
e_vm_default_addr.
Fix all such functions and adopt all callers.
mappings of file objects. move vnode-specific details of mmap()ing a vnode
from uvm_mmap() to the new vnode-specific vn_mmap(). add new uvm_mmap_dev()
and uvm_mmap_anon() convenience functions for mapping character devices
and anonymous memory, and replace all other calls to uvm_mmap() with those.
use the new fileop in drm2 so that libdrm can use mmap() to map things
like on other platforms (instead of the ioctl that we have used so far).
- Add some extra comments.
- Add some XXX comments because the process state might not be stable,
- Add uvm_coredump_count_segs() to simplify the calling code.
- uvm code now only returns non-empty sections/segments.
- Put the 'iocookie' into the 'cookie' block passed to uvm_coredump_walkmap()
instead of passing it through as an additional parameter.
amd64 can still generate core dumps that gdb can read.
from 'void *' to the actual type 'struct coredump_iostate *'.
In most of the code the contents of the structure are still unknown.
This just stops the wrong type of pointer being passed to the 'void *'
parameter.
I hope I've found everything, amd64 GENERIC and i386 GENERIC & ALL compile.
- always provide a vmspace for the new proc, initially borrowing from proc0
(this part fixes PR 46286)
- increase parallelism between parent and child if arguments allow this,
avoiding a potential deadlock on exec_lock
- add a new flag for userland to request old (lockstepped) behaviour for
better error reporting
- adapt test cases to the previous two and add a new variant to test the
diagnostics flag
- fix a few memory (and lock) leaks
- provide netbsd32 compat
simplifying uvm_map handling (no special kernel entries anymore no relocking)
make malloc(9) a thin wrapper around kmem(9)
(with private interface for interrupt safety reasons)
releng@ acknowledged
calls from the mapped region. This can be used for emulation perposed or for
extra security in the case of generated code.
Its implemented by adding mapping-attributes to each uvm_map_entry. These can
then be queried when needed.
Currently the MAP_NOSYSCALLS is only implemented for x86 but other
architectures are easy to adapt; see the sys/arch/x86/x86/syscall.c patch.
Port maintainers are encouraged to add them for their processor ports too.
When this feature is not yet implemented for an architecture the
MAP_NOSYSCALLS is simply ignored with virtually no cpu cost..
When uvm_map gets passed UVM_FLAG_COLORMATCH, the align argument contains
the color of the starting address to be allocated (0..colormask).
When uvm_km_alloc is passed UVM_KMF_COLORMATCH (which can only be used with
UVM_KMF_VAONLY), the align argument contain the color of the starting address
to be allocated.
Change uvm_pagermapin to use this. When mapping user pages in the kernel,
if colormatch is used with the color of the starting user page then the kernel
mapping will be congruent with the existing user mappings.
ubc_zerorange(struct uvm_object *, off_t, size_t, int) changing
the first argument to an uvm_object and adding a flags argument.
Modify tmpfs_reg_resize() to zero the backing store (aobj) instead
of the vnode. Ubc_purge() no longer panics when unmounting tmpfs.
Keep uvm_vnp_zerorange() until the next kernel version bump.
- 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.
allocation for user and system lwps. MIPS will use this to map uareas of
system lwp used direct-mapped addresses (to reduce the overhead of
switching to kernel threads). ibm4xx could use to map uareas via direct
mapped addresses and avoid the problem of having the kernel stack not in
the TLB.
so that VA and PA have the same color. On a page fault, choose a physical
page that has the same color as the virtual address.
When allocating kernel memory pages, allow the MD to specify a preferred
VM_FREELIST from which to choose pages. For machines with large amounts
of memory (> 4GB), all kernel memory to come from <4GB to reduce the amount
of bounce buffering needed with 32bit DMA devices.
in UVM external API, uvm_extern.h. Because most users care only
virtual memory.
Device drivers use bus_dma(9) to manage physical memory. Device
drivers pull in bus_dma(9) API, bus_dma.h. bus_dma(9) implementations
pull in UVM internal API, uvm.h.
Tested By: Compiling i386 ALL kernel
through all LWPs and duplicate locking overhead.
- Move sched_pstats() from soft-interrupt context to process 0 main loop.
Avoids blocking effect on real-time threads. Mostly fixes PR/38792.
Note: it might be worth to move the loop above PRI_PGDAEMON. Also,
sched_pstats() might be cleaned-up slightly.
on the amount of physical memory and limited by NMBCLUSTERS if present.
Architectures without direct mapping also limit it based on the kmem_map
size, which is used as backing store. On i386 and ARM, the maximum KVA
used for mbuf clusters is limited to 64MB by default.
The old default limits and limits based on GATEWAY have been removed.
key_registered_sb_max is hard-wired to a value derived from 2048
clusters.
- Addresses the issue described in PR/38828.
- Some simplification in threading and sleepq subsystems.
- Eliminates pmap_collect() and, as a side note, allows pmap optimisations.
- Eliminates XS_CTL_DATA_ONSTACK in scsipi code.
- Avoids few scans on LWP list and thus potentially long holds of proc_lock.
- Cuts ~1.5k lines of code. Reduces amd64 kernel size by ~4k.
- Removes __SWAP_BROKEN cases.
Tested on x86, mips, acorn32 (thanks <mpumford>) and partly tested on
acorn26 (thanks to <bjh21>).
Discussed on <tech-kern>, reviewed by <ad>.
activity of other threads will perform the TLB flush for the processes using
emap as a side effect. To track that, global and per-CPU generation numbers
are used. This idea was suggested by Andrew Doran; various improvements to
it by me. Notes:
- For now, zero-copy on pipe is not yet enabled.
- TCP socket code would likely need more work.
- Additional UVM loaning improvements are needed.
Proposed on <tech-kern>, silence there.
Quickly reviewed by <ad>.
address space available to processes. this limit exists in most other
modern unix variants, and like most of them, our defaults are unlimited.
remove the old mmap / rlimit.datasize hack.
- adds the VMCMD_STACK flag to all the stack-creation vmcmd callers.
it is currently unused, but was added a few years ago.
- add a pair of new process size values to kinfo_proc2{}. one is the
total size of the process memory map, and the other is the total size
adjusted for unused stack space (since most processes have a lot of
this...)
- patch sh, and csh to notice RLIMIT_AS. (in some cases, the alias
RLIMIT_VMEM was already present and used if availble.)
- patch ps, top and systat to notice the new k_vm_vsize member of
kinfo_proc2{}.
- update irix, svr4, svr4_32, linux and osf1 emulations to support
this information. (freebsd could be done, but that it's best left
as part of the full-update of compat/freebsd.)
this addresses PR 7897. it also gives correct memory usage values,
which have never been entirely correct (since mmap), and have been
very incorrect since jemalloc() was enabled.
tested on i386 and sparc64, build tested on several other platforms.
thanks to many folks for feedback and testing but most espcially
chuq and yamt for critical suggestions that lead to this patch not
having a special ugliness i wasn't happy with anyway :-)
maxv