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Give the device major / minor numbers their own separate 32 bit fields in the kernel. Change dev_ops to use a RB tree to index major device numbers and remove the 256 device major number limitation. Build a dynamic major number assignment feature into dev_ops_add() and adjust ASR (which already had a hand-rolled one), and MFS to use the feature. MFS at least does not require any filesystem visibility to access its backing device. Major devices numbers >= 256 are used for dynamic assignment. Retain filesystem compatibility for device numbers that fall within the range that can be represented in UFS or struct stat (which is a single 32 bit field supporting 8 bit major numbers and 24 bit minor numbers).
Use SYSREF to reference count struct vnode. v_usecount is now v_sysref(.refcnt). v_holdcnt is now v_auxrefs. SYSREF's termination state (using a negative reference count from -0x40000000+) now places the vnode in a VCACHED or VFREE state and deactivates it. The vnode is now assigned a 64 bit unique id via SYSREF. vhold() (which manipulates v_auxrefs) no longer reactivates a vnode and is explicitly used only to track references from auxillary structures and references to prevent premature destruction of the vnode. vdrop() will now only move a vnode from VCACHED to VFREE on the 1->0 transition of v_auxrefs if the vnode is in a termination state. vref() will now panic if used on a vnode in a termination state. vget() must now be used to explicitly reactivate a vnode. These requirements existed before but are now explicitly asserted. vlrureclaim() and allocvnode() should now interact a bit better. In particular, vlrureclaim() will do a better job of finding vnodes to flush and transition from VCACHED to VFREE, and allocvnode() will do a better job finding vnodes to reuse without getting blocked by a flush. allocvnode now uses a real VX lock to sequence vnodes into VRECLAIMED. All vnode special state processing now uses a VX lock. Vnodes are now able to be slowly returned to the memory pool when kern.maxvnodes is reduced at run time. Various initialization elements have been moved to CTOR/DTOR and are no longer in the critical path, improving performance. However, since SYSREF uses atomic_cmpset_int() (aka cmpxchgl), which reduces performance somewhat, overall performance tends to be about the same.
Get rid of struct user/UAREA. Merge procsig with sigacts and replace usage of procsig with sigacts, like it used to be in 4.4BSD. Put signal-related inline functions in sys/signal2.h. Reviewed-by: Thomas E. Spanjaard <firstname.lastname@example.org>
1:1 Userland threading stage 2.20/4: Unify access to pending threads with a new function, lwp_sigpend(), which returns pending signals for the lwp, which includes both lwp-specific signals and signals pending on the process. The new function lwp_delsig() is used to remove a certain signal from the pending set of both process and lwp. Rework the places which access the pending signal list to either use those two functions or, where not possibly, to work on both lwp and proc signal lists.
1:1 Userland threading stage 2.11/4: Move signals into lwps, take p_lwp out of proc. Originally-Submitted-by: David Xu <email@example.com> Reviewed-by: Thomas E. Spanjaard <firstname.lastname@example.org>
Change the kernel dev_t, representing a pointer to a specinfo structure, to cdev_t. Change struct specinfo to struct cdev. The name 'cdev' was taken from FreeBSD. Remove the dev_t shim for the kernel. This commit generally removes the overloading of 'dev_t' between userland and the kernel. Also fix a bug in libkvm where a kernel dev_t (now cdev_t) was not being properly converted to a userland dev_t.
MASSIVE reorganization of the device operations vector. Change cdevsw to dev_ops. dev_ops is a syslink-compatible operations vector structure similar to the vop_ops structure used by vnodes. Remove a huge number of instances where a thread pointer is still being passed as an argument to various device ops and other related routines. The device OPEN and IOCTL calls now take a ucred instead of a thread pointer, and the CLOSE call no longer takes a thread pointer.
Remove several layers in the vnode operations vector init code. Declare the operations vector directly instead of via a descriptor array. Remove most of the recalculation code, it stopped being needed over a year ago. This work is similar to what FreeBSD now does, but was developed along a different line. Ultimately our vop_ops will become SYSLINK ops for userland VFS and clustering support.
* Remove the following obsolete options from the system: AAC_COMPAT_LINUX ACPI_MAX_THREADS AVM_A1_PCI CD9660_ROOT CPU_UPGRADE_HW_CACHE DEBUG_LINUX DEBUG_TOKENS DPT_ALLOW_MEMIO IDE_DELAY INVARIANT_SUPPORT KERNFS MFS_ROOT MFS_ROOT_SIZE NTIMECOUNTER OLTR_NO_BULLSEYE_MAC OLTR_NO_HAWKEYE_MAC OLTR_NO_TMS_MAC UGEN_DEBUG UHCI_DEBUG UHID_DEBUG UHUB_DEBUG UKBD_DEBUG ULPT_DEBUG UMASS_DEBUG UMS_DEBUG VM_KMEM_SIZE VM_KMEM_SIZE_MAX VM_KMEM_SIZE_SCALE * Add numerous options to LINT * Fix typo in options: TWA_FLASH_FIREWARE -> TWA_FLASH_FIRMWARE * Fix typo in dgb.c: opt_depricated.h -> opt_deprecated.h * Fix some minor manpage issues
Remove the thread argument from all mount->vfs_* function vectors, replacing it with a ucred pointer when applicable. This cleans up a considerable amount of VFS function code that previously delved into the process structure to get the cred, though some code remains. Get rid of the compatibility thread argument for hpfs and nwfs. Our lockmgr calls are now mostly compatible with NetBSD (which doesn't use a thread argument either). Get rid of some complex junk in fdesc_statfs() that nobody uses. Remove the thread argument from dounmount() as well as various other filesystem specific procedures (quota calls primarily) which no longer need it due to the lockmgr, VOP, and VFS cleanups. These cleanups also have the effect of making the VFS code slightly less dependant on the calling thread's context.
Remove the thread argument from ffs_flushfiles(), ffs_mountfs(), softdep_flushfiles(), ffs_reload(), ufs_quotaon(), and ufs_quotaoff().
Block devices generally truncate the size of I/O requests which go past EOF. This is exactly what we want when manually reading or writing a block device such as /dev/ad0s1a, but is not desired when a VFS issues I/O ops on filesystem buffers. In such cases, any EOF condition must be considered an error. Implement a new filesystem buffer flag B_BNOCLIP, which getblk() and friends automatically set. If set, block devices are guarenteed to return an error if the I/O request is at EOF or would otherwise have to be clipped to EOF. Block devices further guarentee that b_bcount will not be modified when this flag is set. Adjust all block device EOF checks to use the new flag, and clean up the code while I'm there. Also, set b_resid in a couple of degenerate cases where it was not being set.
Give the MFS pseudo block device vnode a VM object, as is now required for buffer cache operations. Do not try to optimize it for now (i.e. MFS will still double-cache everything).
Use the vnode v_opencount and v_writecount universally. They were previously only used by specfs. Require that VOP_OPEN and VOP_CLOSE calls match. Assert on boundary errors. Clean up umount's FORCECLOSE mode. Adjust deadfs to allow duplicate closes (which can happen due to a forced unmount or revoke). Add vop_stdopen() and vop_stdclose() and adjust the default vnode ops to call them. All VFSs except DEADFS which supply their own vop_open and vop_close now call vop_stdopen() and vop_stdclose() to handle v_opencount and v_writecount adjustments. Change the VOP_OPEN/fp specs. VOP_OPEN (aka vop_stdopen) is now responsible for filling in the file pointer information, rather than the caller of VOP_OPEN. Additionally, when supplied a file pointer, VOP_OPEN is now allowed to populate the file pointer with a different vnode then the one passed to it, which will be used later on to allow filesystems which synthesize different vnodes on open, for example so we can create a generic tty/pty pairing devices rather than scanning for an unused pty, and so we can create swap-backed generic anonymous file descriptors rather than having to use /tmp. And for other purposes as well. Fix UFS's mount/remount/unmount code to make the proper VOP_OPEN and VOP_CLOSE calls when a filesystem is remounted read-only or read-write.
Major BUF/BIO work commit. Make I/O BIO-centric and specify the disk or file location with a 64 bit offset instead of a 32 bit block number. * All I/O is now BIO-centric instead of BUF-centric. * File/Disk addresses universally use a 64 bit bio_offset now. bio_blkno no longer exists. * Stackable BIO's hold disk offset translations. Translations are no longer overloaded onto a single structure (BUF or BIO). * bio_offset == NOOFFSET is now universally used to indicate that a translation has not been made. The old (blkno == lblkno) junk has all been removed. * There is no longer a distinction between logical I/O and physical I/O. * All driver BUFQs have been converted to BIOQs. * BMAP, FREEBLKS, getblk, bread, breadn, bwrite, inmem, cluster_*, and findblk all now take and/or return 64 bit byte offsets instead of block numbers. Note that BMAP now returns a byte range for the before and after variables.
Make the entire BUF/BIO system BIO-centric instead of BUF-centric. Vnode and device strategy routines now take a BIO and must pass that BIO to biodone(). All code which previously managed a BUF undergoing I/O now manages a BIO. The new BIO-centric algorithms allow BIOs to be stacked, where each layer represents a block translation, completion callback, or caller or device private data. This information is no longer overloaded within the BUF. Translation layer linkages remain intact as a 'cache' after I/O has completed. The VOP and DEV strategy routines no longer make assumptions as to which translated block number applies to them. The use the block number in the BIO specifically passed to them. Change the 'untranslated' constant to NOOFFSET (for bio_offset), and (daddr_t)-1 (for bio_blkno). Rip out all code that previously set the translated block number to the untranslated block number to indicate that the translation had not been made. Rip out all the cluster linkage fields for clustered VFS and clustered paging operations. Clustering now occurs in a private BIO layer using private fields within the BIO. Reformulate the vn_strategy() and dev_dstrategy() abstraction(s). These routines no longer assume that bp->b_vp == the vp of the VOP operation, and the dev_t is no longer stored in the struct buf. Instead, only the vp passed to vn_strategy() (and related *_strategy() routines for VFS ops), and the dev_t passed to dev_dstrateg() (and related *_strategy() routines for device ops) is used by the VFS or DEV code. This will allow an arbitrary number of translation layers in the future. Create an independant per-BIO tracking entity, struct bio_track, which is used to determine when I/O is in-progress on the associated device or vnode. NOTE: Unlike FreeBSD's BIO work, our struct BUF is still used to hold the fields describing the data buffer, resid, and error state. Major-testing-by: Stefan Krueger
* Remove (void) casts for discarded return values. * Put function types on separate lines. * Ansify function definitions. In-collaboration-with: Alexey Slynko <email@example.com>
Clean the VFS operations vector and related code: * take advantage of C99 sparse structure initialisation, this allows us to initialise left out vfsops entries cleanly when vfs_register() is called; any vfsop entries that are not specified will be assigned vfs_std* functions. the only exception to this rule is VFS_SYNC which is assigned vfs_stdnosync() since a file system may not have support for it. file systems can simply assign vfs_stdsync if they do not have their own sync operation. * add KKASSERTS to make sure that the VFS_ROOT, VFS_MOUNT and VFS_UNMOUNT vfs operations are provided by a file system being registered. all of the above are necessary to ensure a minimally working file system. * remove scattered no-op definitions of VFS_START() vfsop vector entry and take advantage of sparse vfsop initialisation. VFS_START is only used by MFS to make ensure calling process is not swapped out when I/O is initialised. The entry point is called from the mount path, before the file system is marked ready. * remove scattered no-op definitions of VFS_QUOTACTL() vfsop vector entry and take advantage of sparse vfsop initialisation. * give UFS a VFS_UNINIT vfsop entry and make use of it in ext2fs when ripping down the hash tables. * many file systems in the kernel seem to not implement the complementing VFS_UNINIT() vfsop entry, this is not so much of a problem when the file system is compiled into the kernel, but it can leave leakage when compiled as KLD modules. add uninitialisation code and entry points for ext2fs, ufs, fdescfs. grab the ufs_ihash_token when free'ing the inode hash table at ripping time. * add typedefs for all the vfsop entry points, make use of it in definition of struct vfsops; this results in clean and consolidate code. use the typedefs for vfs_std* function prototypes.
Replace spl with critical sections.
Don't use the statfs field f_mntonname in filesystems. For the userland export code, it can synthesized from mnt_ncp. For debugging code, use f_mntfromname, it should be enough to find culprit. The vfs_unmountall doesn't use code_fullpath to avoid problems with resource allocation and to make it more likely that a call from ddb succeds. Change getfsstat and fhstatfs to not show directories outside a chroot path, with the exception of the filesystem counting the chroot root itself.
VFS messaging/interfacing work stage 10/99: Start adding the journaling, range locking, and (very slightly) cache coherency infrastructure. Continue cleaning up the VOP operations vector. Expand on past commits that gave each mount structure its own set of VOP operations vectors by adding additional vector sets for journaling or cache coherency operations. Remove the vv_jops and vv_cops fields from the vnode operations vector in favor of placing those vop_ops directly in the mount structure. Reorganize the VOP calls as a double-indirect and add a field to the mount structure which represents the current vnode operations set (which will change when e.g. journaling is turned on or off). This creates the infrastructure necessary to allow us to stack a generic journaling implementation on top of a filesystem. Introduce a hard range-locking API for vnodes. This API will be used by high level system/vfs calls in order to handle atomicy guarentees. It is a prerequisit for: (1) being able to break I/O's up into smaller pieces for the vm_page list/direct-to-DMA-without-mapping goal, (2) to support the parallel write operations on a vnode goal, (3) to support the clustered (remote) cache coherency goal, and (4) to support massive parallelism in dispatching operations for the upcoming threaded VFS work. This commit represents only infrastructure and skeleton/API work.
VFS messaging/interfacing work stage 8/99: Major reworking of the vnode interlock and other miscellanious things. This patch also fixes FS corruption due to prior vfs work in head. In particular, prior to this patch the namecache locking could introduce blocking conditions that confuse the old vnode deactivation and reclamation code paths. With this patch there appear to be no serious problems even after two days of continuous testing. * VX lock all VOP_CLOSE operations. * Fix two NFS issues. There was an incorrect assertion (found by David Rhodus), and the nfs_rename() code was not properly purging the target file from the cache, resulting in Stale file handle errors during, e.g. a buildworld with an NFS-mounted /usr/obj. * Fix a TTY session issue. Programs which open("/dev/tty" ,...) and then run the TIOCNOTTY ioctl were causing the system to lose track of the open count, preventing the tty from properly detaching. This is actually a very old BSD bug, but it came out of the woodwork in DragonFly because I am now attempting to track device opens explicitly. * Gets rid of the vnode interlock. The lockmgr interlock remains. * Introduced VX locks, which are mandatory vp->v_lock based locks. * Rewrites the locking semantics for deactivation and reclamation. (A ref'd VX lock'd vnode is now required for vgone(), VOP_INACTIVE, and VOP_RECLAIM). New guarentees emplaced with regard to vnode ripouts. * Recodes the mountlist scanning routines to close timing races. * Recodes getnewvnode to close timing races (it now returns a VX locked and refd vnode rather then a refd but unlocked vnode). * Recodes VOP_REVOKE- a locked vnode is now mandatory. * Recodes all VFS inode hash routines to close timing holes. * Removes cache_leaf_test() - vnodes representing intermediate directories are now held so the leaf test should no longer be necessary. * Splits the over-large vfs_subr.c into three additional source files, broken down by major function (locking, mount related, filesystem syncer). * Changes splvm() protection to a critical-section in a number of places (bleedover from another patch set which is also about to be committed). Known issues not yet resolved: * Possible vnode/namecache deadlocks. * While most filesystems now use vp->v_lock, I haven't done a final pass to make vp->v_lock mandatory and to clean up the few remaining inode based locks (nwfs I think and other obscure filesystems). * NullFS gets confused when you hit a mount point in the underlying filesystem. * Only UFS and NFS have been well tested * NFS is not properly timing out namecache entries, causing changes made on the server to not be properly detected on the client if the client already has a negative-cache hit for the filename in question. Testing-by: David Rhodus <firstname.lastname@example.org>, Peter Kadau <email@example.com>, walt <firstname.lastname@example.org>, others
VFS messaging/interfacing work stage 7/99. BEGIN DESTABILIZATION! Implement the infrastructure required to allow us to begin switching to the new nlookup() VFS API. filedesc->fd_ncdir, fd_nrdir, fd_njdir File descriptors (associated with processes) now record the namecache pointer related to the current directory, root directory, and jail directory, in addition to the vnode pointers. These pointers are used as the basis for the new path lookup code (nlookup() and friends). file->f_ncp File pointers may now have a referenced+unlocked namecache pointer associated with them. All fp's representing directories have this attached. This allows fchdir() to properly record the ncp in fdp->fd_ncdir and friends. mount->mnt_ncp The namecache topology for crossing a mount point works as follows: when looking up a path element which is a mount point, cache_nlookup() will locate the ncp for the vnode-under the mount point. mount->mnt_ncp represents the root of the mount, that is the vnode-over. nlookup() detects the mount point and accesses mount->mnt_ncp to skip past the vnode-under. When going backwards (..), nlookup() detects the case and skips backwards. The ncp linkages are: ncp->ncp->ncp[vnode_under]->ncp[vnode_over]. That is, when going forwards or backwards nlookup must explicitly skip over the double-ncp when crossing a mount point. This allows us to keep the namecache topology intact across mount points. NEW CACHE level API functions: cache_get() Reference and lock a namecache entry cache_put() Dereference and unlock a namecache entry cache_lock() lock an already-referenced namecache entry cache_unlock() unlock a lockednamecache entry NOTE: namecache locks are exclusive and recursive. These are the 'namespace' locks that we will be using to guarentee namespace operations such as in a CREATE, RENAME, or REMOVE. vfs_cache_setroot() Set the new system-wide root directory cache_allocroot() System bootstrap helper function to allocate the root namecache node. cache_resolve() Resolve a NCF_UNRESOLVED namecache node. The namecache node should be locked on call. cache_setvp() (resolver) associate a VP or create a negative cache entry representation for a namecache pointer and clear NCF_UNRESOLVED. The namecache node should be locked on call. cache_setunresolved() Revert a resolved namecache entry back to an unresolved state, disassociating any vnode but leaving the topology intact. The namecache node should be locked on call. cache_vget() Obtain the locked+refd vnode related to a namecache entry, resolving the entry if necessary. Return ENOENT if the entry represents a negative cache hit. cache_vref() Obtained a refd (not locked) vnode related to a namecache entry, as above. cache_nlookup() The new namecache lookup routine. This routine does a lookup and allocates a new namecache node (into an unresolved state) if necessary. Returns a namecache record whether or not the item can be found and whether or not it represents a positive or negative hit. cache_lookup() OLD API CODE DEPRECATED, but must be maintained until everything has been converted over. cache_enter() OLD API CODE DEPRECATED, but must be maintained until everything has been converted over. NEW default VOPs vop_noresolve() Implements a namecache resolver for VFSs which are still using the old VOP_LOOKUP/ VOP_CACHEDLOOKUP API (which is all of them still). VOP_LOOKUP OLD API CODE DEPRECATED, but must be maintained until everything has been converted over. VOP_CACHEDLOOKUP OLD API CODE DEPRECATED, but must be maintained until everything has been converted over. NEW PATHNAME LOOKUP CODE nlookup_init() Similar to NDINIT, initialize a nlookupdata structure for nlookup() and nlookup_done(). nlookup() Lookup a path. Unlike the old namei/lookup code the new lookup code does not do any fancy pre-disposition of the cache for create/delete, it simply looks up the requested path and returns the appropriate locked namecache pointer. The caller can obtain the vnode and directory vnode, as applicable, from the one namecache structure that is returned. Access checks are done on directories leading up to the result but not done on the returned namecache node. nlookup_done() Mandatory routine to cleanup a nlookupdata structure after it has been initialized and all operations have been completed on it. nlookup_simple() (in progress) all-in-one wrapped new lookup. nlookup_mp() helper call for resolving a mount point's glue NCP. hackish, will be cleaned up later. nreadsymlink() helper call to resolve a symlink. Note that the namecache does not yet cache symlink data but the intention is to eventually do so to avoid having to do VFS ops to get the data. naccess() Perform access checks on a namecache node given a mode and cred. naccess_va() Perform access cheks on a vattr given a mode and cred. Begin switching VFS operations from using namei to using nlookup. In this batch: * mount (install mnt_ncp for cross-mount-point handling in nlookup, simplify the vfs_mount() API to no longer pass a nameidata structure) * [l]stat (use nlookup) * [f]chdir (use nlookup, use recorded f_ncp) * [f]chroot (use nlookup, use recorded f_ncp)
VFS messaging/interfacing work stage 4/99. This stage goes a long ways towards allowing us to move the vnode locking into a kernel layer. It gets rid of a lot of cruft from FreeBSD-4. FreeBSD-5 has done some of this stuff too (such as changing the default locking to stdlock from nolock), but DragonFly is going further. * Consolidate vnode locks into the vnode structure, add an embedded v_lock, and getting rid of both v_vnlock and v_data based head-of-structure locks. * Change the default vops to use a standard vnode lock rather then a fake non-lock. * Get rid of vop_nolock() and friends, we no longer support non-locking vnodes. * Get rid of vop_sharedlock(), we no longer support non standard shared-only locks (only NFS was using it and the mount-crossing lookup code should now prevent races to root from dead NFS volumes). * Integrate lock initialization into getnewvnode(). We do not yet incorporate automatically locking into getnewvnode(). getnewvnode() now has two additional arguments, lktimeout and lkflags, for lock structure initialization. * Change the sync vnode lock from nolock to stdlock. This may require more tuning down the line. Fix various sync_inactive() to properly unlock the lock as per the VOP API. * Properly flag the 'rename' vop operation regarding required tdvp and tvp unlocks (the flags are only used by nullfs). * Get rid of all inode-embedded vnode locks * Remove manual lockinit and use new getnewvnode() args instead. Lock the vnode prior to doing anything that might block in order to avoid synclist access before the vnode has been properly initialize. * Generally change inode hash insertion to also check for a hash collision and return failure if it occurs, rather then doing (often non-atomic) relookups and other checks. These sorts of collisions can occur if a vnode is being destroyed at the same time a new vnode is being created from an inode. A new vnode is not generally accessible, except by the sync code (from the mountlist) until it's underlying inode has been hashed so dealing with a hash collision should be as simple as throwing away the vnode with a vput(). * Do not initialize a new vnode's v_data until after the associated inode has been successfully added to the hash, and make the xxx_inactive() and xxx_reclaim() code friendly towards vnodes with a NULL v_data. * NFS now uses standard locks rather then shared-only locks. * PROCFS now uses standard locks rather then non-locks, and PROCFS's lookup code now understands VOP lookup semantics. PROCFS now uses a real hash table for its node search rather then a single singly-linked list (which should better scale to systems with thousands of processes). * NULLFS should now properly handle lookup() and rename() locks. NULLFS's node handling code has been rewritten. NULLFS's bypass code now understands vnode unlocks (rename case). * UFS no longer needs the ffs_inode_hash_lock hacks. It now uses the new collision-on-hash-add methodology. This will speed up UFS when operating on lots of small files (reported by David Rhodus).
VFS messaging/interfacing work stage 1/99. This stage replaces the old dynamic VFS descriptor and inlined wrapper mess with a fixed structure and fixed procedural wrappers. Most of the work is straightforward except for vfs_init, which was basically rewritten (and greatly simplified). It is my intention to make the vop_*() call wrappers eventually handle range locking and cache coherency issues as well as implementing the direct call -> messaging interface layer. The call wrappers will also API translation as we shift the APIs over to new, more powerful mechanisms in order to allow the work to be incrementally committed. This is the first stage of what is likely to be a huge number of stages to modernize the VFS subsystem.
Device layer rollup commit. * cdevsw_add() is now required. cdevsw_add() and cdevsw_remove() may specify a mask/match indicating the range of supported minor numbers. Multiple cdevsw_add()'s using the same major number, but distinctly different ranges, may be issued. All devices that failed to call cdevsw_add() before now do. * cdevsw_remove() now automatically marks all devices within its supported range as being destroyed. * vnode->v_rdev is no longer resolved when the vnode is created. Instead, only v_udev (a newly added field) is resolved. v_rdev is resolved when the vnode is opened and cleared on the last close. * A great deal of code was making rather dubious assumptions with regards to the validity of devices associated with vnodes, primarily due to the persistence of a device structure due to being indexed by (major, minor) instead of by (cdevsw, major, minor). In particular, if you run a program which connects to a USB device and then you pull the USB device and plug it back in, the vnode subsystem will continue to believe that the device is open when, in fact, it isn't (because it was destroyed and recreated). In particular, note that all the VFS mount procedures now check devices via v_udev instead of v_rdev prior to calling VOP_OPEN(), since v_rdev is NULL prior to the first open. * The disk layer's device interaction has been rewritten. The disk layer (i.e. the slice and disklabel management layer) no longer overloads its data onto the device structure representing the underlying physical disk. Instead, the disk layer uses the new cdevsw_add() functionality to register its own cdevsw using the underlying device's major number, and simply does NOT register the underlying device's cdevsw. No confusion is created because the device hash is now based on (cdevsw,major,minor) rather then (major,minor). NOTE: This also means that underlying raw disk devices may use the entire device minor number instead of having to reserve the bits used by the disk layer, and also means that can we (theoretically) stack a fully disklabel-supported 'disk' on top of any block device. * The new reference counting scheme prevents this by associating a device with a cdevsw and disconnecting the device from its cdevsw when the cdevsw is removed. Additionally, all udev2dev() lookups run through the cdevsw mask/match and only successfully find devices still associated with an active cdevsw. * Major work on MFS: MFS no longer shortcuts vnode and device creation. It now creates a real vnode and a real device and implements real open and close VOPs. Additionally, due to the disk layer changes, MFS is no longer limited to 255 mounts. The new limit is 16 million. Since MFS creates a real device node, mount_mfs will now create a real /dev/mfs<PID> device that can be read from userland (e.g. so you can dump an MFS filesystem). * BUF AND DEVICE STRATEGY changes. The struct buf contains a b_dev field. In order to properly handle stacked devices we now require that the b_dev field be initialized before the device strategy routine is called. This required some additional work in various VFS implementations. To enforce this requirement, biodone() now sets b_dev to NODEV. The new disk layer will adjust b_dev before forwarding a request to the actual physical device. * A bug in the ISO CD boot sequence which resulted in a panic has been fixed. Testing by: lots of people, but David Rhodus found the most aggregious bugs.
device switch 1/many: Remove d_autoq, add d_clone (where d_autoq was). d_autoq was used to allow the device port dispatch to mix old-style synchronous calls with new style messaging calls within a particular device. It was never used for that purpose. d_clone will be more fully implemented as work continues. We are going to install d_port in the dev_t (struct specinfo) structure itself and d_clone will be needed to allow devices to 'revector' the port on a minor-number by minor-number basis, in particular allowing minor numbers to be directly dispatched to distinct threads. This is something we will be needing later on.
Style(9) cleanup to src/sys/vfs, stage 8/21: mfs. - Convert K&R-style function definitions to ANSI style. Submitted-by: Andre Nathan <email@example.com> Additional-reformatting-by: cpressey
Add a missing PRELE() when the mfs_mount kernel process exits. Because DragonFly does not teardown zombie processes while p_lock is non-zero this prevented such processes from being reaped and deadlocked the init process.
__P()!=wanted, remove old style prototypes from the vfs subtree
kernel tree reorganization stage 1: Major cvs repository work (not logged as commits) plus a major reworking of the #include's to accomodate the relocations. * CVS repository files manually moved. Old directories left intact and empty (temporary). * Reorganize all filesystems into vfs/, most devices into dev/, sub-divide devices by function. * Begin to move device-specific architecture files to the device subdirs rather then throwing them all into, e.g. i386/include * Reorganize files related to system busses, placing the related code in a new bus/ directory. Also move cam to bus/cam though this may not have been the best idea in retrospect. * Reorganize emulation code and place it in a new emulation/ directory. * Remove the -I- compiler option in order to allow #include file localization, rename all config generated X.h files to use_X.h to clean up the conflicts. * Remove /usr/src/include (or /usr/include) dependancies during the kernel build, beyond what is normally needed to compile helper programs. * Make config create 'machine' softlinks for architecture specific directories outside of the standard <arch>/include. * Bump the config rev. WARNING! after this commit /usr/include and /usr/src/sys/compile/* should be regenerated from scratch.
Register keyword removal Approved by: Matt Dillon
Have MFS register a device as a VCHR instead of VBLK, fixing a panic. Report-by: Joerg Sonnenberger <firstname.lastname@example.org>
DEV messaging stage 1/4: Rearrange struct cdevsw and add a message port and auto-queueing mask. The mask will tell us which message functions can be safely queued to another thread and which still need to run in the context of the caller. Primary configuration fields (name, cmaj, flags, port, autoq mask) are now at the head of the structure. Function vectors, which may eventually go away, are at the end. The port and autoq fields are non-functional in this stage. The old BDEV device major number support has also been removed from cdevsw, and code has been added to translate the bootdev passed from the boot code (the boot code has always passed the now defunct block device major numbers and we obviously need to keep that compatibility intact).
Remove the priority part of the priority|flags argument to tsleep(). Only flags are passed now. The priority was a user scheduler thingy that is not used by the LWKT subsystem. For process statistics assume sleeps without P_SINTR set to be disk-waits, and sleeps with it set to be normal sleeps. This commit should not contain any operational changes.
MP Implementation 1/2: Get the APIC code working again, sweetly integrate the MP lock into the LWKT scheduler, replace the old simplelock code with tokens or spin locks as appropriate. In particular, the vnode interlock (and most other interlocks) are now tokens. Also clean up a few curproc/cred sequences that are no longer needed. The APs are left in degenerate state with non IPI interrupts disabled as additional LWKT work must be done before we can really make use of them, and FAST interrupts are not managed by the MP lock yet. The main thing for this stage was to get the system working with an APIC again. buildworld tested on UP and 2xCPU/MP (Dell 2550)
proc->thread stage 4: rework the VFS and DEVICE subsystems to take thread pointers instead of process pointers as arguments, similar to what FreeBSD-5 did. Note however that ultimately both APIs are going to be message-passing which means the current thread context will not be useable for creds and descriptor access.
thread stage 5: Separate the inline functions out of sys/buf.h, creating sys/buf2.h (A methodology that will continue as time passes). This solves inline vs struct ordering problems. Do a major cleanup of the globaldata access methodology. Create a gcc-cacheable 'mycpu' macro & inline to access per-cpu data. Atomicy is not required because we will never change cpus out from under a thread, even if it gets preempted by an interrupt thread, because we want to be able to implement per-cpu caches that do not require locked bus cycles or special instructions.
Add the DragonFly cvs id and perform general cleanups on cvs/rcs/sccs ids. Most ids have been removed from !lint sections and moved into comment sections.
import from FreeBSD RELENG_4 126.96.36.199