src/sys/dev/md, branch release/8.1.0

MFC r204408:

2010-03-27T14:43:40Z

Fix panic on invalid 'mdconfig -at preload' usage. PR: kern/80136

MFC r201145 to stable/8:

2010-01-30T12:11:21Z

(S)LIST_HEAD_INITIALIZER takes a (S)LIST_HEAD as an argument. Fix some wrong usages. Note: this does not affect generated binaries as this argument is not used. PR: 137213 Submitted by: Eygene Ryabinkin (initial version)

Implement global and per-uid accounting of the anonymous memory. Add

2009-06-23T20:45:22Z

rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved for the uid. The accounting information (charge) is associated with either map entry, or vm object backing the entry, assuming the object is the first one in the shadow chain and entry does not require COW. Charge is moved from entry to object on allocation of the object, e.g. during the mmap, assuming the object is allocated, or on the first page fault on the entry. It moves back to the entry on forks due to COW setup. The per-entry granularity of accounting makes the charge process fair for processes that change uid during lifetime, and decrements charge for proper uid when region is unmapped. The interface of vm_pager_allocate(9) is extended by adding struct ucred *, that is used to charge appropriate uid when allocation if performed by kernel, e.g. md(4). Several syscalls, among them is fork(2), may now return ENOMEM when global or per-uid limits are enforced. In collaboration with: pho Reviewed by: alc Approved by: re (kensmith)

Add cpu_flush_dcache() for use after non-DMA based I/O so that a

2009-05-18T18:37:18Z

possible future I-cache coherency operation can succeed. On ARM for example the L1 cache can be (is) virtually mapped, which means that any I/O that uses temporary mappings will not see the I-cache made coherent. On ia64 a similar behaviour has been observed. By flushing the D-cache, execution of binaries backed by md(4) and/or NFS work reliably. For Book-E (powerpc), execution over NFS exhibits SIGILL once in a while as well, though cpu_flush_dcache() hasn't been implemented yet. Doing an explicit D-cache flush as part of the non-DMA based I/O read operation eliminates the need to do it as part of the I-cache coherency operation itself and as such avoids pessimizing the DMA-based I/O read operations for which D-cache are already flushed/invalidated. It also allows future optimizations whereby the bcopy() followed by the D-cache flush can be integrated in a single operation, which could be implemented using on-chips DMA engines, by-passing the D-cache altogether.

Add a new internal mount flag (MNTK_EXTENDED_SHARED) to indicate that a

2009-03-11T14:13:47Z

filesystem supports additional operations using shared vnode locks. Currently this is used to enable shared locks for open() and close() of read-only file descriptors. - When an ISOPEN namei() request is performed with LOCKSHARED, use a shared vnode lock for the leaf vnode only if the mount point has the extended shared flag set. - Set LOCKSHARED in vn_open_cred() for requests that specify O_RDONLY but not O_CREAT. - Use a shared vnode lock around VOP_CLOSE() if the file was opened with O_RDONLY and the mountpoint has the extended shared flag set. - Adjust md(4) to upgrade the vnode lock on the vnode it gets back from vn_open() since it now may only have a shared vnode lock. - Don't enable shared vnode locks on FIFO vnodes in ZFS and UFS since FIFO's require exclusive vnode locks for their open() and close() routines. (My recent MPSAFE patches for UDF and cd9660 already included this change.) - Enable extended shared operations on UFS, cd9660, and UDF. Submitted by: ups Reviewed by: pjd (ZFS bits) MFC after: 1 month

Remove unnecessary page queues locking around vm_page_wakeup(). (This

2009-02-22T02:50:31Z

change is applicable to RELENG_7 but not RELENG_6.) MFC after: 1 week

Add the possibility to specify "-o force" with "mdconfig -du".

2009-01-10T17:17:18Z

Reviewed by: scottl Approved by: rwatson (mentor) Sponsored by: FreeBSD Foundation

Fix forced mdconfig -du. E.g. the following would previously

2008-12-16T20:59:27Z

result in panic: mdconfig -af blah.img -o force mount /dev/md0 /mnt mdconfig -du 0 Reviewed by: scottl Approved by: rwatson (mentor) Sponsored by: FreeBSD Foundation

Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread

2008-08-28T15:23:18Z

was always curthread and totally unuseful. Tested by: Giovanni Trematerra

Remove the distinction between device minor and unit numbers.

2008-05-29T12:50:46Z

Even though we got rid of device major numbers some time ago, device drivers still need to provide unique device minor numbers to make_dev(). These numbers are only used inside the kernel. They are not related to device major and minor numbers which are visible in devfs. These are actually based on the inode number of the device. It would eventually be nice to remove minor numbers entirely, but we don't want to be too agressive here. Because the 8-15 bits of the device number field (si_drv0) are still reserved for the major number, there is no 1:1 mapping of the device minor and unit numbers. Because this is now unused, remove the restrictions on these numbers. The MAXMAJOR definition was actually used for two purposes. It was used to convert both the userspace and kernelspace device numbers to their major/minor pair, which is why it is now named UMINORMASK. minor2unit() and unit2minor() have now become useless. Both minor() and dev2unit() now serve the same purpose. We should eventually remove some of them, at least turning them into macro's. If devfs would become completely minor number unaware, we could consider using si_drv0 directly, just like si_drv1 and si_drv2. Approved by: philip (mentor)