This means that MmSystemCacheStart, MmSystemCacheEnd, MmSizeOfSystemCacheInPages
have now a valid value.
System cache is not used atm the moment though. MmMapViewInSystemCache() is to
be implemented, and Cc is to be made aware of this.
CORE-14259
- Change MM_SYSTEM_SPACE_START to 0xFFFFF88000000000
- Move MI_DEBUG_MAPPING to the end of the system PTE range
- Add MI_SYSTEM_CACHE_START and MI_SYSTEM_CACHE_END, which is in the range that Vista uses as dynamic VA space for cache and other allocations
- Wrap x86 specific code that makes now invalid assumptions about the address space layout in #ifdef _M_IX86
- CcUnpinDataForThread() only release VACB when the last BCB reference is gone. This avoids having a valid BCB with an invalid VACB
- CcRosMarkDirtyVacb() will only accept non-dirty VACB now. This avoids a major bug where a an already dirty VACB was over-dereferenced
- Thanks to previous point, simplify CcRosUnmapVacb(), CcRosReleaseVacb() implementation
- And only set VACB dirty once in CcSetDirtyPinnedData()
- Add a few sanity checks
With that I can again install ReactOS with 128MB RAM :-).
CORE-14263
CORE-14268
Namely, implement CcSetDirtyPageThreshold() and add support for it
in CcCanIWrite().
Also added my name in the headers of the few files I touched tonight.
CORE-14235
Namely, implement CcCanIWrite() (very basic, and likely wrong).
And implement CcDeferWrite() which will queue the write operation.
In CciLazyWriter() (which may be renamed CcWorkerThread() ;-)),
handle the queued write operations one by one. This is likely
not to be accurate, but, given we have only on FS supporting
this for now (NFS / RDBSS / Shares), this is OK.
CORE-14235
Experiment and MSDN tend to show that a dirty BCB is queued for lazy write.
This will do the job here!
Also, renamed CcRosMarkDirtyFile() which is more accurate, and added a new
function CcRosMarkDirtyVacb() which just takes a VACB as arg (expected locked)
and marks it dirty (using previous implementation). Make CcRosMarkDirtyFile()
use it.
CORE-14235
CcDirtyPageThreshold is not here to compute when you have to write,
but to know where you have to deny writes.
More commits to come in that direction!
CORE-14235
This removes the "modified page writer" thread in Mm that was regularly blindly
attempting to flush dirty pages to the disk.
Instead, this commit introduces a lazy writer that will monitor dirty pages count
and will flush them to disk when this count is above a threshold. The threshold is
computed on Cc init.
Compared to what was done previously, this lazy writer will only write down files
that are not marked as temporary.
The mechanisms involved in this lazy writer worker are well described in Windows
Internals 4th editions (constants are coming from it ;-)).
Also fixed a bad (and old!) bug in CcRosFlushDirtyPages() where target count could
be overflow and the function would spin forever while holding the VACBs lock. This is
mandatory as now lazy writer will call it with "random" values.
This also allows implementing CcWaitForCurrentLazyWriterActivity() :-).
Also renamed DirtyPageCount to its MS equivalent.
CORE-14235
This would affect reads/writes on large volumes where offset is higher than what a ULONG can hold.
This really nasty bug was hitting CcMapData() but also CcPinRead() (due to the nature of its implementation)
and both were returning garbage data under certain circumstances with Ext2Fsd.
This should (I hope!) help some other FSDs to work better in ROS.
CORE-12456
Note: before we had a BOOLEAN parameter called StoreInstruction, but in reality it was not specifying whether the fault was from a store store instruction, but whether it was an access violation rather than a page-not-present fault. On x86 without PAE there are only 2 kinds of access violations: (1) Access of a kernel mode page from user mode, which is handled early and (2) access of a read-only (or COW) page with a writing instruction. Therefore we could get away with this, even though it relied on the wrong assumption that a fault, which was not a page-not-present-fault, was automatically a write access. This commit only changes one thing: we pass the full fault-code to MmAccessFault and handle the rest from there in exactly the same way as before. More changes are coming to make things clear.
Based on an original patch by Timo Kreuzer, with modifications by me to adapt it to latest HEAD and use a single exit path through the Cleanup label. This reliably frees all allocated handles.
The original code returns STATUS_SUCCESS for many cases. This has been preserved.
In the future, it should be checked though whether returning success is appropriate for all these cases.
CORE-6844
