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>
This commit is contained in:
Akinobu Mita 2011-08-03 16:21:01 -07:00 committed by Linus Torvalds
parent f48d1915b8
commit dd48c085c1
7 changed files with 33 additions and 46 deletions

View file

@ -143,8 +143,7 @@ o provide a way to configure fault attributes
failslab, fail_page_alloc, and fail_make_request use this way.
Helper functions:
init_fault_attr_dentries(entries, attr, name);
void cleanup_fault_attr_dentries(entries);
fault_create_debugfs_attr(name, parent, attr);
- module parameters

View file

@ -1368,8 +1368,10 @@ static bool should_fail_request(struct hd_struct *part, unsigned int bytes)
static int __init fail_make_request_debugfs(void)
{
return init_fault_attr_dentries(&fail_make_request,
"fail_make_request");
struct dentry *dir = fault_create_debugfs_attr("fail_make_request",
NULL, &fail_make_request);
return IS_ERR(dir) ? PTR_ERR(dir) : 0;
}
late_initcall(fail_make_request_debugfs);

View file

@ -28,7 +28,10 @@ int blk_should_fake_timeout(struct request_queue *q)
static int __init fail_io_timeout_debugfs(void)
{
return init_fault_attr_dentries(&fail_io_timeout, "fail_io_timeout");
struct dentry *dir = fault_create_debugfs_attr("fail_io_timeout",
NULL, &fail_io_timeout);
return IS_ERR(dir) ? PTR_ERR(dir) : 0;
}
late_initcall(fail_io_timeout_debugfs);

View file

@ -25,10 +25,6 @@ struct fault_attr {
unsigned long reject_end;
unsigned long count;
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
struct dentry *dir;
#endif
};
#define FAULT_ATTR_INITIALIZER { \
@ -45,19 +41,15 @@ bool should_fail(struct fault_attr *attr, ssize_t size);
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
int init_fault_attr_dentries(struct fault_attr *attr, const char *name);
void cleanup_fault_attr_dentries(struct fault_attr *attr);
struct dentry *fault_create_debugfs_attr(const char *name,
struct dentry *parent, struct fault_attr *attr);
#else /* CONFIG_FAULT_INJECTION_DEBUG_FS */
static inline int init_fault_attr_dentries(struct fault_attr *attr,
const char *name)
{
return -ENODEV;
}
static inline void cleanup_fault_attr_dentries(struct fault_attr *attr)
static inline struct dentry *fault_create_debugfs_attr(const char *name,
struct dentry *parent, struct fault_attr *attr)
{
return ERR_PTR(-ENODEV);
}
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */

View file

@ -197,21 +197,15 @@ static struct dentry *debugfs_create_atomic_t(const char *name, mode_t mode,
return debugfs_create_file(name, mode, parent, value, &fops_atomic_t);
}
void cleanup_fault_attr_dentries(struct fault_attr *attr)
{
debugfs_remove_recursive(attr->dir);
}
int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
struct dentry *fault_create_debugfs_attr(const char *name,
struct dentry *parent, struct fault_attr *attr)
{
mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
struct dentry *dir;
dir = debugfs_create_dir(name, NULL);
dir = debugfs_create_dir(name, parent);
if (!dir)
return -ENOMEM;
attr->dir = dir;
return ERR_PTR(-ENOMEM);
if (!debugfs_create_ul("probability", mode, dir, &attr->probability))
goto fail;
@ -243,11 +237,11 @@ int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
return 0;
return dir;
fail:
debugfs_remove_recursive(attr->dir);
debugfs_remove_recursive(dir);
return -ENOMEM;
return ERR_PTR(-ENOMEM);
}
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */

View file

@ -34,23 +34,23 @@ __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;
int err;
err = init_fault_attr_dentries(&failslab.attr, "failslab");
if (err)
return err;
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, failslab.attr.dir,
if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
&failslab.ignore_gfp_wait))
goto fail;
if (!debugfs_create_bool("cache-filter", mode, failslab.attr.dir,
if (!debugfs_create_bool("cache-filter", mode, dir,
&failslab.cache_filter))
goto fail;
return 0;
fail:
cleanup_fault_attr_dentries(&failslab.attr);
debugfs_remove_recursive(dir);
return -ENOMEM;
}

View file

@ -1409,14 +1409,11 @@ static int __init fail_page_alloc_debugfs(void)
{
mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
struct dentry *dir;
int err;
err = init_fault_attr_dentries(&fail_page_alloc.attr,
"fail_page_alloc");
if (err)
return err;
dir = fail_page_alloc.attr.dir;
dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
&fail_page_alloc.attr);
if (IS_ERR(dir))
return PTR_ERR(dir);
if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
&fail_page_alloc.ignore_gfp_wait))
@ -1430,7 +1427,7 @@ static int __init fail_page_alloc_debugfs(void)
return 0;
fail:
cleanup_fault_attr_dentries(&fail_page_alloc.attr);
debugfs_remove_recursive(dir);
return -ENOMEM;
}