linux/lib
FUJITA Tomonori 75f1cdf1dd x86: Handle HW IOMMU initialization failure gracefully
If HW IOMMU initialization fails (Intel VT-d often does this,
typically due to BIOS bugs), we fall back to nommu. It doesn't
work for the majority since nowadays we have more than 4GB
memory so we must use swiotlb instead of nommu.

The problem is that it's too late to initialize swiotlb when HW
IOMMU initialization fails. We need to allocate swiotlb memory
earlier from bootmem allocator. Chris explained the issue in
detail:

  http://marc.info/?l=linux-kernel&m=125657444317079&w=2

The current x86 IOMMU initialization sequence is too complicated
and handling the above issue makes it more hacky.

This patch changes x86 IOMMU initialization sequence to handle
the above issue cleanly.

The new x86 IOMMU initialization sequence are:

1. we initialize the swiotlb (and setting swiotlb to 1) in the case
   of (max_pfn > MAX_DMA32_PFN && !no_iommu). dma_ops is set to
   swiotlb_dma_ops or nommu_dma_ops. if swiotlb usage is forced by
   the boot option, we finish here.

2. we call the detection functions of all the IOMMUs

3. the detection function sets x86_init.iommu.iommu_init to the
   IOMMU initialization function (so we can avoid calling the
   initialization functions of all the IOMMUs needlessly).

4. if the IOMMU initialization function doesn't need to swiotlb
   then sets swiotlb to zero (e.g. the initialization is
   sucessful).

5. if we find that swiotlb is set to zero, we free swiotlb
   resource.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: chrisw@sous-sol.org
Cc: dwmw2@infradead.org
Cc: joerg.roedel@amd.com
Cc: muli@il.ibm.com
LKML-Reference: <1257849980-22640-10-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-10 12:32:07 +01:00
..
lzo lzo: use get/put_unaligned_* helpers 2008-07-25 10:53:26 -07:00
reed_solomon lib: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:17:17 -04:00
zlib_deflate trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +02:00
zlib_inflate bzip2/lzma: library support for gzip, bzip2 and lzma decompression 2009-01-04 15:53:34 -08:00
.gitignore
argv_split.c LIB: Replace inappropriate include of <linux/bug.h> 2007-10-20 00:26:10 +02:00
atomic64.c lib: export generic atomic64_t functions 2009-07-29 19:10:35 -07:00
audit.c [PATCH] audit signal recipients 2007-05-11 05:38:25 -04:00
bcd.c rtc: BCD codeshrink 2008-07-24 10:47:33 -07:00
bitmap.c Make bitmask 'and' operators return a result code 2009-08-21 09:26:15 -07:00
bitrev.c lib: export bitrev16 2008-06-06 11:29:10 -07:00
bug.c allow bug table entries to use relative pointers (and use it on x86-64) 2008-12-16 18:40:32 +01:00
bust_spinlocks.c oops handling: ensure that any oops is flushed to the mtdoops console 2009-01-06 15:59:11 -08:00
check_signature.c uninline check_signature() 2007-07-16 09:05:50 -07:00
checksum.c lib/checksum.c: fix endianess bug 2009-06-19 14:58:13 +02:00
cmdline.c generic, memparse(): constify argument 2008-07-28 15:05:23 +02:00
cpumask.c x86: remove some alloc_bootmem_cpumask_var calling 2009-06-11 19:27:07 +03:00
crc7.c CRC7 support 2007-07-17 10:23:04 -07:00
crc16.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc32.c lib/: Spelling fixes 2008-02-03 17:48:52 +02:00
crc32defs.h
crc-ccitt.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc-itu-t.c CRC ITU-T V.41 2007-05-10 18:24:13 +02:00
crc-t10dif.c [SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC 2008-07-12 08:22:32 -05:00
ctype.c
debug_locks.c lockdep: warn about lockdep disabling after kernel taint 2009-04-12 16:10:51 +02:00
debugobjects.c headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
dec_and_lock.c atomic: only take lock when the counter drops to zero on UP as well 2009-06-16 19:47:47 -07:00
decompress_bunzip2.c lib/decompress_*: only include <linux/slab.h> if STATIC is not defined 2009-08-07 10:39:56 -07:00
decompress_inflate.c lzma/gzip: fix potential oops when input data is truncated 2009-09-24 07:21:05 -07:00
decompress_unlzma.c lzma/gzip: fix potential oops when input data is truncated 2009-09-24 07:21:05 -07:00
decompress.c bzip2/lzma: don't stop search at first unconfigured compression 2009-02-19 13:36:55 -08:00
devres.c [POWERPC] devres: Add devm_ioremap_prot() 2008-05-05 16:47:14 +10:00
div64.c add an inlined version of iter_div_u64_rem 2008-06-12 10:47:58 +02:00
dma-debug.c dma-debug: Fix compile warning with PAE enabled 2009-10-29 16:25:50 +01:00
dump_stack.c
dynamic_debug.c Dynamic debug: fix typo: -/-> 2009-07-28 13:45:22 -07:00
extable.c module: trim exception table on init free. 2009-06-12 21:47:04 +09:30
fault-inject.c headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
find_last_bit.c bitmap: find_last_bit() 2009-01-01 10:12:19 +10:30
find_next_bit.c bitops: remove "optimizations" 2008-04-29 08:11:16 -07:00
flex_array.c flex_array: add missing kerneldoc annotations 2009-09-22 07:17:47 -07:00
gcd.c lib: add lib/gcd.c 2009-06-18 13:04:05 -07:00
gen_crc32table.c
genalloc.c lib/genalloc.c: remove unmatched write_lock() in gen_pool_destroy 2009-06-16 19:47:53 -07:00
halfmd4.c
hexdump.c hexdump: remove the trailing space 2009-06-16 19:47:51 -07:00
hweight.c remove asm/bitops.h includes 2007-10-19 11:53:41 -07:00
idr.c cgroup: CSS ID support 2009-04-02 19:04:53 -07:00
inflate.c Nicolas Pitre has a new email address 2009-09-15 09:37:12 -07:00
int_sqrt.c
iomap_copy.c [PATCH] add __iowrite64_copy 2006-06-20 20:24:58 -07:00
iomap.c Use WARN() in lib/ 2008-07-26 12:00:07 -07:00
iommu-helper.c introduce generic iommu_num_pages function 2008-10-16 11:21:33 -07:00
ioremap.c lib/ioremap.c should #include <linux/io.h> 2007-10-17 08:42:50 -07:00
irq_regs.c [PATCH] irq_reqs: export __irq_regs 2006-10-06 08:53:40 -07:00
is_single_threaded.c kernel: is_current_single_threaded: don't use ->mmap_sem 2009-07-17 09:11:31 +10:00
kasprintf.c lib: move kasprintf to a separate file 2007-07-31 15:39:39 -07:00
Kconfig lib: Provide generic atomic64_t implementation 2009-06-15 13:27:38 +10:00
Kconfig.debug powerpc: Minor cleanup to lib/Kconfig.debug 2009-10-27 16:42:42 +11:00
Kconfig.kgdb kgdb: remove the requirement for CONFIG_FRAME_POINTER 2008-08-01 08:39:34 -05:00
Kconfig.kmemcheck kmemcheck: depend on HAVE_ARCH_KMEMCHECK 2009-07-01 22:28:44 +02:00
kernel_lock.c sched: TIF_NEED_RESCHED -> need_reshed() cleanup 2009-03-06 12:48:55 +01:00
klist.c driver core: Remove completion from struct klist_node 2009-01-06 10:44:30 -08:00
kobject_uevent.c driver core: allow non-root users to listen to uevents 2009-04-16 16:17:09 -07:00
kobject.c kobject: make kset_create check kobject_set_name return value 2009-06-15 21:30:24 -07:00
kref.c kref: add kref_set() 2008-01-24 20:40:05 -08:00
libcrc32c.c libcrc32c: Fix "crc32c undefined" compilation error 2008-12-25 11:01:42 +11:00
list_debug.c list debugging: use WARN() instead of BUG() 2008-07-25 10:53:29 -07:00
lmb.c lmb: Remove __init from lmb_end_of_DRAM() 2009-08-27 12:25:26 -07:00
locking-selftest-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-mutex.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest.c locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit] 2009-03-13 01:32:36 +01:00
Makefile lib: flexible array implementation 2009-07-29 19:10:36 -07:00
nlattr.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6 2009-03-26 22:45:23 -07:00
parser.c vfs: Use const for kernel parser table 2008-10-13 10:10:37 -07:00
percpu_counter.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-06 17:10:04 -08:00
plist.c Use WARN() in lib/ 2008-07-26 12:00:07 -07:00
prio_heap.c lib: fix sparse shadowed variable warning 2009-01-06 15:59:11 -08:00
prio_tree.c
proportions.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-06 17:10:04 -08:00
radix-tree.c lib: do code optimization for radix_tree_lookup() and radix_tree_lookup_slot() 2009-06-16 19:47:49 -07:00
random32.c random32: seeding improvement 2008-07-30 16:29:19 -07:00
ratelimit.c __ratelimit() cpu flags can't be static 2008-07-28 16:30:20 -07:00
rational.c lib: isolate rational fractions helper function 2009-06-11 08:51:08 -07:00
rbtree.c rb_tree: remove redundant if()-condition in rb_erase() 2009-06-16 19:47:56 -07:00
reciprocal_div.c [PATCH] SLAB: use a multiply instead of a divide in obj_to_index() 2006-12-13 09:05:49 -08:00
rwsem-spinlock.c lib: remove fastcall from lib/* 2008-02-08 09:22:31 -08:00
rwsem.c x86: fix UML and -regparm=3 2008-01-30 13:33:00 +01:00
scatterlist.c lib/scatterlist: add a flags to signalize mapping direction 2009-07-31 12:28:45 +02:00
sha1.c [PATCH] Numerous fixes to kernel-doc info in source files. 2007-02-11 10:51:32 -08:00
show_mem.c lib: generic show_mem() 2008-07-26 12:00:10 -07:00
smp_processor_id.c cpumask: convert lib/smp_processor_id to new cpumask ops 2009-01-30 15:47:34 +01:00
sort.c generic swap(): lib/sort.c: rename swap to swap_func 2009-01-08 08:31:14 -08:00
spinlock_debug.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
string_helpers.c [SCSI] lib: string_get_size(): don't hang on zero; no decimals on exact 2008-10-23 11:42:20 -05:00
string.c Add a new sysfs_streq() string comparison function 2008-05-01 08:03:59 -07:00
swiotlb.c x86: Handle HW IOMMU initialization failure gracefully 2009-11-10 12:32:07 +01:00
syscall.c task_current_syscall 2008-07-26 12:00:10 -07:00
textsearch.c remove CONFIG_KMOD from lib 2008-07-22 19:24:31 +10:00
ts_bm.c textsearch: ts_bm: support case insensitive searching in Boyer-Moore algorithm 2008-07-08 02:37:54 -07:00
ts_fsm.c textsearch: ts_fsm: return error on request for case insensitive search 2008-07-08 02:38:27 -07:00
ts_kmp.c textsearch: ts_kmp: support case insensitive searching in Knuth-Morris-Pratt algorithm 2008-07-08 02:38:09 -07:00
vsprintf.c sscanf(): fix %*s%n 2009-10-01 16:11:16 -07:00