diff options
author | Douglas Gilbert <dgilbert@interlog.com> | 2009-08-19 01:35:02 +0000 |
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committer | Douglas Gilbert <dgilbert@interlog.com> | 2009-08-19 01:35:02 +0000 |
commit | 6fa85931942a499d92e193cfa3150d2a62f6ffc8 (patch) | |
tree | 628eb8ac5ea991759b9587759c811e0bc49354ff /README.win32 | |
parent | 6857c006538197ca621fbdc85719b46f3d865f8f (diff) | |
download | sg3_utils-6fa85931942a499d92e193cfa3150d2a62f6ffc8.tar.gz |
rework sg_pt_win32.c to have extendable non-direct SPT; change default back to 'non-direct'; add './configure --enable-win32-spt-direct'
git-svn-id: https://svn.bingwo.ca/repos/sg3_utils/trunk@288 6180dd3e-e324-4e3e-922d-17de1ae2f315
Diffstat (limited to 'README.win32')
-rw-r--r-- | README.win32 | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/README.win32 b/README.win32 index 6e2d6a4b..943e1f5a 100644 --- a/README.win32 +++ b/README.win32 @@ -76,6 +76,32 @@ See the INSTALL file (towards the end) for instructions on how to build sg3_utils on Windows operating systems. Some man pages have examples which use linux device names which hopefully will not confuse Windows users. +Two pass-through variants +========================= +The sg_pt_win32.c file uses the Windows SCSI Pass Through interface. +That is often shortened to SPT or SPTI. There are two DeviceIoControl() +ioctl variants provided: IOCTL_SCSI_PASS_THROUGH and +IOCTL_SCSI_PASS_THROUGH_DIRECT. The former involves double handling of +data (and perhaps an upper limit on the data length associated with +one SCSI command; MS documentation mentions 16 KB). The "direct" +variant passes a pointer from the user space and to be faster looks +and more versatile. + +However the "direct" variant has potentially (unquantified) alignment +requirements and may not be (well) implemented by the hardware driver. +In practice some users have reported errors (e.g. 1117: a non-descript +IO error) when the direct variant is used. + +Hence the non-direct variant is the default. The default size limit +on the data buffer is set at 16 KB but if the user asks for more +the data buffer will be extended. The OS or the hardware drivers +may reject the extended data buffer but we tried. + +The package can be built using the direct variant with: + ./configure --enable-win32-spt-direct +rather than: + ./configure +prior to the 'make' call. Details ======= @@ -90,11 +116,11 @@ operating system: - sg_pt_osf1.c [Tru64] - sg_pt_win32.c -The sg_pt_win32.c file uses the Windows SCSI Pass Through (SPT) mechanism. -It does not currently use the ASPI32 interface which requires a dll from -Adaptec. The sg_scan utility is a special version for Windows and it attempts -to show the various available storage device names, one per line. Here is an -example of sg_scan's output: +The ASPI32 interface which requires a dll from Adaptec ia not supported. + +The sg_scan utility is a special version for Windows and it attempts to show +the various available storage device names, one per line. Here is an example +of sg_scan's output: # sg_scan PD0 [C] FUJITSU MHY2160BH 0000 @@ -165,4 +191,4 @@ mode" with the setmode() Windows command. Doug Gilbert -15th June 2009 +18th August 2009 |