[patch] zero-bounce block highmem I/O, #13

[Jens Axboe]

Hi,

I've uploaded a new version. Changes since last time includes the
following:

- Merge BIO_CONTIG from 2.5 bio patches to unify testing of contigious
  buffer heads (BH_CONTIG in 2.4 tree) (me)

- cciss, cpqarray, and ide-dma wrongly used 0 for lastdataend in segment
  merging, which is wrong since 0 is a valid physical address. A case of
  s/NULL/0 substition when changing from virtual to physical tests.
  (davem)

- cciss/cpqarray - drop my_sg list, just use the kernel supplied
  scatterlist. my_sg used unsigned short for length, which is too small.
  (pointed out by davem, fixed by me)

- cciss/cpqarray - rewrite loop-until-empty in request queueing. (me)

- BLK_BOUNCE_ANY was b0rken, the ->bounce_page would wrap and thus not
  work. (pointed davem out by davem, fixed by me -- temporarily, will
  change to test for highest page instead in next version)

- Always use 64-bit type for BLK_BOUNCE_ANY (davem)

- IPS must check number of segments mapped by pci_map_sg instead of
  using the SCSI supplied sg count. (pointed out by davem, fixed by me).
  IPS still has some highmem fixes pending.

2.4.9 version is here:

*.kernel.org/pub/linux/kernel/people/axboe/patches/2.4.9/block-highmem-all-13

2.4.8-ac12 version is here:

*.kernel.org/pub/linux/kernel/people/axboe/patches/2.4.8-ac12/block-highmem-all-13-ac12

-- 
Jens Axboe