From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/scsi/lpfc.txt | 83 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 Documentation/scsi/lpfc.txt (limited to 'Documentation/scsi/lpfc.txt') diff --git a/Documentation/scsi/lpfc.txt b/Documentation/scsi/lpfc.txt new file mode 100644 index 00000000..5741ea8a --- /dev/null +++ b/Documentation/scsi/lpfc.txt @@ -0,0 +1,83 @@ + +LPFC Driver Release Notes: + +============================================================================= + + + IMPORTANT: + + Starting in the 8.0.17 release, the driver began to be targeted strictly + toward the upstream kernel. As such, we removed #ifdefs for older kernels + (pre 2.6.10). The 8.0.16 release should be used if the driver is to be + run on one of the older kernels. + + The proposed modifications to the transport layer for FC remote ports + and extended attribute support is now part of the upstream kernel + as of 2.6.12. We no longer need to provide patches for this support, + nor a *full* version which has old an new kernel support. + + The driver now requires a 2.6.12 (if pre-release, 2.6.12-rc1) or later + kernel. + + Please heed these dependencies.... + + + ******************************************************************** + + +The following information is provided for additional background on the +history of the driver as we push for upstream acceptance. + +Cable pull and temporary device Loss: + + In older revisions of the lpfc driver, the driver internally queued i/o + received from the midlayer. In the cases where a cable was pulled, link + jitter, or a device temporarily loses connectivity (due to its cable + being removed, a switch rebooting, or a device reboot), the driver could + hide the disappearance of the device from the midlayer. I/O's issued to + the LLDD would simply be queued for a short duration, allowing the device + to reappear or link come back alive, with no inadvertent side effects + to the system. If the driver did not hide these conditions, i/o would be + errored by the driver, the mid-layer would exhaust its retries, and the + device would be taken offline. Manual intervention would be required to + re-enable the device. + + The community supporting kernel.org has driven an effort to remove + internal queuing from all LLDDs. The philosophy is that internal + queuing is unnecessary as the block layer already performs the + queuing. Removing the queues from the LLDD makes a more predictable + and more simple LLDD. + + As a potential new addition to kernel.org, the 8.x driver was asked to + have all internal queuing removed. Emulex complied with this request. + In explaining the impacts of this change, Emulex has worked with the + community in modifying the behavior of the SCSI midlayer so that SCSI + devices can be temporarily suspended while transport events (such as + those described) can occur. + + The proposed patch was posted to the linux-scsi mailing list. The patch + is contained in the 2.6.10-rc2 (and later) patch kits. As such, this + patch is part of the standard 2.6.10 kernel. + + By default, the driver expects the patches for block/unblock interfaces + to be present in the kernel. No #define needs to be set to enable support. + + +Kernel Support + + This source package is targeted for the upstream kernel only. (See notes + at the top of this file). It relies on interfaces that are slowing + migrating into the kernel.org kernel. + + At this time, the driver requires the 2.6.12 (if pre-release, 2.6.12-rc1) + kernel. + + If a driver is needed for older kernels please utilize the 8.0.16 + driver sources. + + +Patches + + Thankfully, at this time, patches are not needed. + + -- cgit v1.2.3