allocate with the vm_cache locked - this is necessary to be able to steal pages
from itself (large files...).
The system doesn't actually lock up anymore, but it still renders itself unusable;
obviously the page thief does not work correctly, yet. The rest of the experience
is created by our current scheduler (the page thief runs and runs, but it doesn't
free any pages anymore).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22466 a95241bf-73f2-0310-859d-f6bbb57e9c96
twice into the same cache: cache_io() called read_into_cache() (or
write_to_cache()), and that broke down the request into smaller parts.
It then called read_chunk_into_cache() (or write_chunk_to_cache() resp.)
to actually allocate pages and fulfill the request.
However, it needed to unlock the cache for each chunk, and in the mean
time someone else could insert pages into the remaining chunks.
* Now, cache_io() already takes care of chunking the data which makes this
approach safe, and also simplified the code a bit - read_into_cache()/
write_to_cache() are gone now. I've renamed read_chunk_into_cache() to
read_into_cache() (same for the write function).
* Also got rid of that goto in that function while I was on it.
* Disabled cache_prefetch_vnode() for now (it's similar to cache_io(), but
since it's currently not used [since no cache module is installed yet],
I didn't want to go through updating it now, too).
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* the page writer don't allow to block, while all other writers do. This fixes
bug #1509. The reason the page writer needs this is because it marks several
pages from different caches as busy.
* Fixed a warning about ASSERT being defined already in BFS, since
util/DoublyLinkedList.h now includes debug.h.
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is tracked while the page scanner runs much slower. Now, we just set it to a
fixed positive, so that they can easily age in case they are actually unused.
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are locked, there is now a vm_page_reserve_pages() call to ensure upfront that
there is a page for me when I need it, and may have locked some caches.
* The vm_soft_fault() routine now makes use of that feature.
* vm_page_allocate_page() now resets the vm_page::usage_count, so that the file
cache does not need to do this in read_chunk_into_cache() and
write_chunk_to_cache().
* In cache_io() however, it need to update the usage_count - and it does that
now. Since non-mapped caches don't have mappings, the page scanner will punish
the cache pages stronger than other pages which is accidently just what we
want.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22319 a95241bf-73f2-0310-859d-f6bbb57e9c96
* Removed the vm_cache/vm_store ref_count duality that besides being a bit ugly
also created the page dameon cache retrieval problem: now, only areas (and
cache consumers) retrieve a reference to the store (and therefore, the vnode).
The page daemon doesn't need to care about this at all anymore, and the pseudo
references of the vm_cache could be removed again.
* Rearranged deletion of vnodes such that its ID can be reused directly after
fs_remove_vnode() has been called.
* vm_page_allocate_page() no longer panics when it runs out of pages, but just
waits for new pages to become available using the new sFreeCondition condition
variable - to make sure this happens in an acceptable time frame, it'll
trigger a run of the low memory handlers.
* Implemented a page_thief() that steals inactive pages from caches and puts
them into the free queue. It runs as a low memory handler.
* The file cache now sets the usage count on the pages it inserts into the
cache (needs some rework though, cache_io() doesn't do it yet).
* Instead of panicking, the kernel will currently dead lock in low memory
situations, since BFS does a bit too much in bfs_release_vnode().
* Some minor cleanup.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22315 a95241bf-73f2-0310-859d-f6bbb57e9c96
correct values (resolving a TODO); however, the latter doesn't do anything
with those yet.
* Cleanup.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22154 a95241bf-73f2-0310-859d-f6bbb57e9c96
since fault_find_page() does no longer insert a dummy page into a cache
that has a store from which it can read the page.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21887 a95241bf-73f2-0310-859d-f6bbb57e9c96
* Removed a few instances where the page state was set busy directly after
allocating it. This is a no-op, since a page is always busy after
allocation.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21875 a95241bf-73f2-0310-859d-f6bbb57e9c96
removed in several cases.
* vfs_get_vnode_cache() now always gives out a reference to the cache it
returns; if it needs to allocate a new one, the vnode owns one reference,
and the caller another.
* therefore, file_cache_create() now owns a reference to its vm_cache_ref, and
frees it in file_cache_delete().
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small to hold the information for the requested I/O size.
* get_file_map() returned B_BUFFER_OVERFLOW already in case the array
was exactly as large as needed.
* read_chunk_into_cache() and write_chunk_to_cache() will no longer
override their local "size" variable.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20509 a95241bf-73f2-0310-859d-f6bbb57e9c96
* Added a few comments.
* Simplified the nested while loops by dropping the special handling for the
first iovec and restructuring the innermost loop. This also rules out
the possibility of a zero-length temporary vec. IMHO the readability
has improved quite a bit (YMMV :-). Hopefully without introducing new
bugs; please review!
* Corrected computation of totalSize in case less than size has been
read/written.
* Also set *_numBytes in case all fileVecs have been processed. Only
relevant in case the request extends beyond the end of file.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20483 a95241bf-73f2-0310-859d-f6bbb57e9c96
filling them which could have written over the stack, and their iovec length
was set for the wrong iovec, potentially clobbering any memory.
* The first tempVec was usually empty, anyway, as the wrong iovec was chosen
to start from (usually one too early).
* The tempVec loop is now repeated until the whole fileVec is completed.
* Minor cleanup.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20476 a95241bf-73f2-0310-859d-f6bbb57e9c96
will now grab a reference to the vnode as well if successful. This way, vfs_get_vnode_cache()
now actually works how it should: it will now always grab a reference to the cache and
its underlying vnode. This removes an extra reference to the vnode (and vm_cache) that
got ignored before and prevented volumes to be unmounted (or file caches to be removed).
Thanks to Korli for pointing this out.
* file_cache_create() is now aware of that extra vnode reference and releases it; unmounting
volumes is now working again as it should.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@18716 a95241bf-73f2-0310-859d-f6bbb57e9c96
into more than MAX_FILE_IO_VECS pieces. This could have very weird consequences
like overwriting data outside the file (but on that same partition only).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17536 a95241bf-73f2-0310-859d-f6bbb57e9c96
reading the file map of certain files (hope I got that more or less
right)
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17525 a95241bf-73f2-0310-859d-f6bbb57e9c96
systems a chance to know if they have locked already.
This fixes a locking problem in BFS where one thread tried to acquire two read
locks (where someone else trying to acquire a write lock would have caused a
dead lock).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17108 a95241bf-73f2-0310-859d-f6bbb57e9c96
since it unlocked the cache while waiting on a busy page. Now, we're filling
the pending request before unlocking the cache.
* Fixed the deadlock I mentioned in the last commit: if a page fault happens
at the same time we're trying to read/write from/to a page, we no longer
fight for the BFS inode lock, but eventually doing the job twice if needed.
Will need to go over the "write modified" functions to make sure they are
behaving as well.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17091 a95241bf-73f2-0310-859d-f6bbb57e9c96
vm_cache_ref starts with a reference count of 1. When acquiring a vm_cache,
you no longer need to worry if that should go through the vm_store, or not;
as it now always does.
* map_backing_store() no longer needs to play with the vm_cache_ref
references.
* that simplified some code.
* vfs_get_vnode_cache() now grabs a reference to the cache, if successful.
* better balanced vnode ownership on vnode_store creation (vnode_store
released the vnode before if its creation failed).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15641 a95241bf-73f2-0310-859d-f6bbb57e9c96
this saves 4 bytes per page. To compensate the loss of bytes, the offset is now
stored in page size units, that's enough to address 2^44 or 16 TB (which is now
the maximal supported file size!).
* Renamed vm_page::ppn to physical_page_number.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15637 a95241bf-73f2-0310-859d-f6bbb57e9c96
will no longer panic, but free its allocated pages.
I ran into this because BFS managed to create a file without data stream but
with a length larger than 0...
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15093 a95241bf-73f2-0310-859d-f6bbb57e9c96
about our block_io module not honouring the total length in read_pages().
Removed drops into the debugger when there is a block without an "original"
data buffer - that's completely normal and happens when someone asks for
a cleared block that is not yet in the cache.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14437 a95241bf-73f2-0310-859d-f6bbb57e9c96
to it - if that page was read from disk unmodified before (or written back in
the mean time), the updated contents coult not be detected, and therefore, were
never written back.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14048 a95241bf-73f2-0310-859d-f6bbb57e9c96
was incorrectly calculated, and could therefore cause all sorts of troubles with
writes over 4 kB.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14011 a95241bf-73f2-0310-859d-f6bbb57e9c96
only a read lock on the inode, or without a lock at all (in case of prefetching) - it
is now using the cache_ref's lock to make sure it's retrieved only once and doesn't
waste/corrupts any memory.
- since that fix made it mandatory to fix write_chunk_into_cache() to not call pages_io()
while holding the cache_ref's lock (was a to-do item before), I changed it to make
that possible.
- It now also supports write-through caches in theory - as there is no way yet to tell
a cache to work this way.
- Optimized for the not so uncommon case of writing the last part of a file that is not
a multiple of the page size - it won't call pages_io() anymore then, but zero the rest
of the page directly.
- vm_page_write_modified() is now calling write_page() without holding the cache_ref's
lock as well.
The updated write_chunk_to_cache() is not so well tested, though, but appears to work
so far.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14006 a95241bf-73f2-0310-859d-f6bbb57e9c96
get_file_map() now seems to work correctly in all regular cases.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13947 a95241bf-73f2-0310-859d-f6bbb57e9c96
- under certain situations, the wrong extent could be chosen (off-by-one error)
- the resulting length of the first vector was incorrectly calculated for all
extents but the first
Improved error checking a bit.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13941 a95241bf-73f2-0310-859d-f6bbb57e9c96
prevents the system to allocate caches for files that don't use or have
a file cache (ie. only those can be mmap()ed!).
Therefore, cache_prefetch() no longer crashes when trying to prefetch
files without a file cache.
read_into_cache() no longer does anything if the requested size is 0.
Fixed a bug in cache_prefetch_vnode(): if the cache couldn't be retrieved,
it put the vnode, but didn't own it (the caller does).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13904 a95241bf-73f2-0310-859d-f6bbb57e9c96
device becomes available.
Currently, it opens the "launch_speedup" module (if available), later it
should consult a settings file for what to do.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13894 a95241bf-73f2-0310-859d-f6bbb57e9c96
tested for fragmented files - but it seems to work good enough for now.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13870 a95241bf-73f2-0310-859d-f6bbb57e9c96
Removed vfs_vnode_release_ref(), as vfs_put_vnode() already does the same thing.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13867 a95241bf-73f2-0310-859d-f6bbb57e9c96
the other one with usual device/inode ID pair.
Both versions now accept an offset/size pair to specify the region of the
file to be prefetched - this may be turned into a file_vec_io array later on.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13866 a95241bf-73f2-0310-859d-f6bbb57e9c96
This is needed in case the on-disk representation of a file changes (due to reorganization/defragmentation).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13660 a95241bf-73f2-0310-859d-f6bbb57e9c96
Axel Dörfler