lwn.git/drivers/lguest/core.c, branch v3.3.5

lguest: move process freezing before pending signals check

2011-10-27T00:26:18+00:00

run_guest tries to freeze the current process after it has handled pending interrupts and before it calls lguest_arch_run_guest. This doesn't work nicely if the task has been killed while being frozen and when we want to handle that signal as soon as possible. Let's move try_to_freeze before we check for pending signal so that we can get out of the loop as soon as possible. Signed-off-by: Michal Hocko Acked-by: Rusty Russell Signed-off-by: Rusty Russell

lguest: Allow running under paravirt-enabled KVM.

2011-10-27T00:26:17+00:00

We actually can run under KVM, as it doesn't paravirtualize anything we need to use; reduce the check to checking we are the normal ringlevel. Reported-by: Stefanos Geraggelos Signed-off-by: Rusty Russell # HG changeset patch

lguest: update comments

2011-07-22T05:09:50+00:00

Also removes a long-unused #define and an extraneous semicolon. Signed-off-by: Rusty Russell

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32+00:00

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

lguest: cleanup for map_switcher()

2009-09-23T12:56:47+00:00

We can use alloc_page() instead of get_zeroed_page() and virt_to_page() Signed-off-by: Xiao Guangrong Signed-off-by: Rusty Russell

lguest: update commentry

2009-07-30T06:33:46+00:00

Every so often, after code shuffles, I need to go through and unbitrot the Lguest Journey (see drivers/lguest/README). Since we now use RCU in a simple form in one place I took the opportunity to expand that explanation. Signed-off-by: Rusty Russell Cc: Ingo Molnar Cc: Paul McKenney

lguest: fix comment style

2009-07-30T06:33:45+00:00

I don't really notice it (except to begrudge the extra vertical space), but Ingo does. And he pointed out that one excuse of lguest is as a teaching tool, it should set a good example. Signed-off-by: Rusty Russell Cc: Ingo Molnar

lguest: remove obsolete LHREQ_BREAK call

2009-06-12T12:57:11+00:00

We no longer need an efficient mechanism to force the Guest back into host userspace, as each device is serviced without bothering the main Guest process (aka. the Launcher). Signed-off-by: Rusty Russell

lguest: use eventfds for device notification

2009-06-12T12:57:10+00:00

Currently, when a Guest wants to perform I/O it calls LHCALL_NOTIFY with an address: the main Launcher process returns with this address, and figures out what device to run. A far nicer model is to let processes bind an eventfd to an address: if we find one, we simply signal the eventfd. Signed-off-by: Rusty Russell Cc: Davide Libenzi

lguest: map switcher with executable page table entries

2009-06-12T12:57:06+00:00

Map switcher with executable page table entries. (This bug didn't matter before PAE and hence NX support -- RR) Signed-off-by: Matias Zabaljauregui Signed-off-by: Rusty Russell