linux/include
James Bottomley dde2020754 libata: eliminate the home grown dma padding in favour of
that provided by the block layer

ATA requires that all DMA transfers begin and end on word boundaries.
Because of this, a large amount of machinery grew up in ide to adjust
scatterlists on this basis.  However, as of 2.5, the block layer has a
dma_alignment variable which ensures both the beginning and length of a
DMA transfer are aligned on the dma_alignment boundary.  Although the
block layer does adjust the beginning of the transfer to ensure this
happens, it doesn't actually adjust the length, it merely makes sure
that space is allocated for transfers beyond the declared length.  The
upshot of this is that scatterlists may be padded to any size between
the actual length and the length adjusted to the dma_alignment safely
knowing that memory is allocated in this region.

Right at the moment, SCSI takes the default dma_aligment which is on a
512 byte boundary.  Note that this aligment only applies to transfers
coming in from user space.  However, since all kernel allocations are
automatically aligned on a minimum of 32 byte boundaries, it is safe to
adjust them in this manner as well.

tj: * Adjusting sg after padding is done in block layer.  Make libata
      set queue alignment correctly for ATAPI devices and drop broken
      sg mangling from ata_sg_setup().
    * Use request->raw_data_len for ATAPI transfer chunk size.
    * Killed qc->raw_nbytes.
    * Separated out killing qc->n_iter.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:56 +01:00
..
acpi ACPI, cpuidle: Clarify C-state description in sysfs 2008-02-14 00:09:55 -05:00
asm-alpha CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-arm Merge branches 'master', 'omap1-upstream' and 'orion' into devel 2008-02-09 22:47:23 +00:00
asm-avr32 CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-blackfin Add pgtable_t to remaining nommu architectures 2008-02-09 11:08:33 -08:00
asm-cris Merge branch 'cris' of git://www.jni.nu/cris 2008-02-08 10:01:28 -08:00
asm-frv Fix FRV cmpxchg_local 2008-02-08 15:33:32 -08:00
asm-generic Make topology fallback macros reference their arguments. 2008-02-11 20:37:29 -08:00
asm-h8300 Add pgtable_t to remaining nommu architectures 2008-02-09 11:08:33 -08:00
asm-ia64 [IA64] Fix build for sim_defconfig 2008-02-11 13:23:46 -08:00
asm-m32r CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-m68k CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-m68knommu m68knommu: use tabs not spaces in cacheflush.h 2008-02-14 20:58:05 -08:00
asm-mips CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-mn10300 Final removal of FASTCALL()/fastcall 2008-02-13 16:21:18 -08:00
asm-parisc CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
asm-powerpc [POWERPC] Wire up new timerfd syscalls 2008-02-14 22:11:01 +11:00
asm-ppc [POWERPC] Fix arch/ppc compilation - add typedef for pgtable_t 2008-02-14 22:11:02 +11:00
asm-s390 [S390] dynamic page tables. 2008-02-09 18:24:41 +01:00
asm-sh sh: fix ioreadN_rep and iowriteN_rep 2008-02-14 14:25:37 +09:00
asm-sparc [SPARC]: Merge asm-sparc{,64}/a.out.h 2008-02-09 22:25:50 -08:00
asm-sparc64 [SPARC]: Merge asm-sparc{,64}/a.out.h 2008-02-09 22:25:50 -08:00
asm-um uml: x86_64 should copy %fs during fork 2008-02-08 09:22:43 -08:00
asm-v850 Add pgtable_t to remaining nommu architectures 2008-02-09 11:08:33 -08:00
asm-x86 x86: zap invalid and unused pmds in early boot 2008-02-18 20:54:14 +01:00
asm-xtensa fix xtensa timerfd breakage 2008-02-08 15:33:32 -08:00
crypto
keys
linux libata: eliminate the home grown dma padding in favour of 2008-02-19 11:36:56 +01:00
math-emu
media V4L/DVB (7192): Adds support for Genius TVGo A11MCE 2008-02-18 11:15:19 -03:00
mtd
net [IPSEC]: Fix bogus usage of u64 on input sequence number 2008-02-12 22:50:35 -08:00
pcmcia
rdma IB/core: Remove unused struct ib_device.flags member 2008-02-08 14:47:26 -08:00
rxrpc
scsi [SCSI] update SG_ALL to avoid causing chaining 2008-02-11 13:40:13 -06:00
sound
video
xen
Kbuild