return value when it could return 1 (indicating we should stop).
Fix a few instances of pager_open() / pager_close() not being called.
Actually use these routines for the environment variable printing code
I just committed.
The block cache implementation in loader has proven to be almost useless, and in worst case even slowing down the disk reads due to insufficient cache size and extra memory copy.
Also the current cache implementation does not cache reads from CDs, or work with zfs built on top of multiple disks.
Instead of an LRU, this code uses a simple hash (O(1) read from cache), and instead of a single global cache, a separate cache per block device.
The cache also implements limited read-ahead to increase performance.
To simplify read ahead management, the read ahead will not wrap over bcache end, so in worst case, single block physical read will be performed to fill the last block in bcache.
Booting from a virtual CD over IPMI:
0ms latency, before: 27 second, after: 7 seconds
60ms latency, before: over 12 minutes, after: under 5 minutes.
Submitted by: Toomas Soome <tsoome@me.com>
Reviewed by: delphij (previous version), emaste (previous version)
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D4713
ubldr.
The changes are mostly dealing with removing unnecessary casts from the U-Boot
API (we're passing only pointers, no obvious reason to cast them to uint32_t),
cleaning up some compiler warnings and using the proper printf format
specifiers in order to be able to compile cleanly for both 32-bit and 64-bit
MIPS targets.
Reviewed by: imp
Approved by: adrian (mentor)
Sponsored by: Smartcom - Bulgaria AD
Differential Revision: https://reviews.freebsd.org/D5312
setting the u-boot environment variable loaderdev=. It used to accept only
'disk' or 'net'. Now it allows specification of unit, slice, and partition
as well. In addition to the generic 'disk' it also accepts specific
storage device types such as 'mmc' or 'sata'.
If there isn't a loaderdev env var, the historical behavior is maintained.
It will use the first storage device it finds, or a network device if
no working storage device exists.
99% of the work on this was done by Patrick Kelsey, but I made some
changes, so if anything goes wrong, blame me.
Submitted by: Patrick Kelsey <kelsey@ieee.org>
disk_open(). Very often this is called several times for one file.
This leads to reading partition table metadata for each call. To
reduce the number of disk I/O we have a simple block cache, but it
is very dumb and more than half of I/O operations related to reading
metadata, misses this cache.
Introduce new cache layer to resolve this problem. It is independent
and doesn't need initialization like bcache, and will work by default
for all loaders which use the new DISK API. A successful disk_open()
call to each new disk or partition produces new entry in the cache.
Even more, when disk was already open, now opening of any nested
partitions does not require reading top level partition table.
So, if without this cache, partition table metadata was read around
20-50 times during boot, now it reads only once. This affects the booting
from GPT and MBR from the UFS.
- Only non-sliced bsdlabel style partitioning is currently supported (but provisions
are made towards GPT support, which should follow soon)
- Enable storage support in loader on ARM
Obtained from: Semihalf
