linux-stable/mm/failslab.c
Akinobu Mita dd48c085c1 fault-injection: add ability to export fault_attr in arbitrary directory
init_fault_attr_dentries() is used to export fault_attr via debugfs.
But it can only export it in debugfs root directory.

Per Forlin is working on mmc_fail_request which adds support to inject
data errors after a completed host transfer in MMC subsystem.

The fault_attr for mmc_fail_request should be defined per mmc host and
export it in debugfs directory per mmc host like
/sys/kernel/debug/mmc0/mmc_fail_request.

init_fault_attr_dentries() doesn't help for mmc_fail_request.  So this
introduces fault_create_debugfs_attr() which is able to create a
directory in the arbitrary directory and replace
init_fault_attr_dentries().

[akpm@linux-foundation.org: extraneous semicolon, per Randy]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Tested-by: Per Forlin <per.forlin@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-03 14:25:20 -10:00

60 lines
1.3 KiB
C

#include <linux/fault-inject.h>
#include <linux/slab.h>
static struct {
struct fault_attr attr;
u32 ignore_gfp_wait;
int cache_filter;
} failslab = {
.attr = FAULT_ATTR_INITIALIZER,
.ignore_gfp_wait = 1,
.cache_filter = 0,
};
bool should_failslab(size_t size, gfp_t gfpflags, unsigned long cache_flags)
{
if (gfpflags & __GFP_NOFAIL)
return false;
if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT))
return false;
if (failslab.cache_filter && !(cache_flags & SLAB_FAILSLAB))
return false;
return should_fail(&failslab.attr, size);
}
static int __init setup_failslab(char *str)
{
return setup_fault_attr(&failslab.attr, str);
}
__setup("failslab=", setup_failslab);
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
static int __init failslab_debugfs_init(void)
{
struct dentry *dir;
mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
if (IS_ERR(dir))
return PTR_ERR(dir);
if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
&failslab.ignore_gfp_wait))
goto fail;
if (!debugfs_create_bool("cache-filter", mode, dir,
&failslab.cache_filter))
goto fail;
return 0;
fail:
debugfs_remove_recursive(dir);
return -ENOMEM;
}
late_initcall(failslab_debugfs_init);
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */