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* Replace all calls to minor() with dev2unit().ed2008-09-271-2/+2
| | | | | | | | | | | | | | | After I removed all the unit2minor()/minor2unit() calls from the kernel yesterday, I realised calling minor() everywhere is quite confusing. Character devices now only have the ability to store a unit number, not a minor number. Remove the confusion by using dev2unit() everywhere. This commit could also be considered as a bug fix. A lot of drivers call minor(), while they should actually be calling dev2unit(). In -CURRENT this isn't a problem, but it turns out we never had any problem reports related to that issue in the past. I suspect not many people connect more than 256 pieces of the same hardware. Reviewed by: kib
* Remove unneeded D_NEEDMINOR from cpuctl(4).ed2008-09-011-1/+0
| | | | | | | | | | The D_NEEDMINOR flag was introduced for drivers that do not actually depend on storing a device unit/minor number, but require the ability to address the cdevs by this number, which is used by clone_create(). The cpuctl(4) driver sets D_NEEDMINOR, even though it doesn't use the clone_create() API. Remove the flag, because maybe we want to get rid of it somewhere in the far future.
* - Add cpuctl(4) pseudo-device driver to provide access to some low-levelstas2008-08-081-0/+446
features of CPUs like reading/writing machine-specific registers, retrieving cpuid data, and updating microcode. - Add cpucontrol(8) utility, that provides userland access to the features of cpuctl(4). - Add subsequent manpages. The cpuctl(4) device operates as follows. The pseudo-device node cpuctlX is created for each cpu present in the systems. The pseudo-device minor number corresponds to the cpu number in the system. The cpuctl(4) pseudo- device allows a number of ioctl to be preformed, namely RDMSR/WRMSR/CPUID and UPDATE. The first pair alows the caller to read/write machine-specific registers from the correspondent CPU. cpuid data could be retrieved using the CPUID call, and microcode updates are applied via UPDATE. The permissions are inforced based on the pseudo-device file permissions. RDMSR/CPUID will be allowed when the caller has read access to the device node, while WRMSR/UPDATE will be granted only when the node is opened for writing. There're also a number of priv(9) checks. The cpucontrol(8) utility is intened to provide userland access to the cpuctl(4) device features. The utility also allows one to apply cpu microcode updates. Currently only Intel and AMD cpus are supported and were tested. Approved by: kib Reviewed by: rpaulo, cokane, Peter Jeremy MFC after: 1 month
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