From dd48c085c1cdf9446f92826f1fd451167fb6c2fd Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Wed, 3 Aug 2011 16:21:01 -0700 Subject: [PATCH] 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 Tested-by: Per Forlin Cc: Jens Axboe Cc: Christoph Lameter Cc: Pekka Enberg Cc: Matt Mackall Cc: Randy Dunlap Cc: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../fault-injection/fault-injection.txt | 3 +-- block/blk-core.c | 6 ++++-- block/blk-timeout.c | 5 ++++- include/linux/fault-inject.h | 18 +++++------------ lib/fault-inject.c | 20 +++++++------------ mm/failslab.c | 14 ++++++------- mm/page_alloc.c | 13 +++++------- 7 files changed, 33 insertions(+), 46 deletions(-) diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt index 7be15e44d481..82a5d250d75e 100644 --- a/Documentation/fault-injection/fault-injection.txt +++ b/Documentation/fault-injection/fault-injection.txt @@ -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 diff --git a/block/blk-core.c b/block/blk-core.c index b850bedad229..b627558c461f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -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); diff --git a/block/blk-timeout.c b/block/blk-timeout.c index 4f0c06c7a338..780354888958 100644 --- a/block/blk-timeout.c +++ b/block/blk-timeout.c @@ -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); diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index 3ff060ac7810..c6f996f2abb6 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -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 */ diff --git a/lib/fault-inject.c b/lib/fault-inject.c index 2577b121c7c1..f193b7796449 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -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 */ diff --git a/mm/failslab.c b/mm/failslab.c index 1ce58c201dca..0dd7b8fec71c 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -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; } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1dbcf8888f14..6e8ecb6e021c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -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; }