72626685dc
Most awkward part of this is delaying write requests until bitmap updates have been flushed. To achieve this, we have a sequence number (seq_flush) which is incremented each time the raid5 is unplugged. If the raid thread notices that this has changed, it flushes bitmap changes, and assigned the value of seq_flush to seq_write. When a write request arrives, it is given the number from seq_write, and that write request may not complete until seq_flush is larger than the saved seq number. We have a new queue for storing stripes which are waiting for a bitmap flush and an extra flag for stripes to record if the write was 'degraded' and so should not clear the a bit in the bitmap. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| acpi | ||
| asm-alpha | ||
| asm-arm | ||
| asm-arm26 | ||
| asm-cris | ||
| asm-frv | ||
| asm-generic | ||
| asm-h8300 | ||
| asm-i386 | ||
| asm-ia64 | ||
| asm-m32r | ||
| asm-m68k | ||
| asm-m68knommu | ||
| asm-mips | ||
| asm-parisc | ||
| asm-powerpc | ||
| asm-ppc | ||
| asm-ppc64 | ||
| asm-s390 | ||
| asm-sh | ||
| asm-sh64 | ||
| asm-sparc | ||
| asm-sparc64 | ||
| asm-um | ||
| asm-v850 | ||
| asm-x86_64 | ||
| asm-xtensa | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| video | ||