From 425cb02912d1095febfeaf8d379af7b2ac9e4a89 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Thu, 12 Feb 2009 10:56:59 -0700 Subject: [PATCH] sysfs: sysfs_add_one WARNs with full path to duplicate filename sysfs: sysfs_add_one WARNs with full path to duplicate filename As a debugging aid, it can be useful to know the full path to a duplicate file being created in sysfs. We now will display warnings such as: sysfs: cannot create duplicate filename '/foo' when attempting to create multiple files named 'foo' in the sysfs root, or: sysfs: cannot create duplicate filename '/bus/pci/slots/5/foo' when attempting to create multiple files named 'foo' under a given directory in sysfs. The path displayed is always a relative path to sysfs_root. The leading '/' in the path name refers to the sysfs_root mount point, and should not be confused with the "real" '/'. Thanks to Alex Williamson for essentially writing sysfs_pathname. Cc: Alex Williamson Signed-off-by: Alex Chiang Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 82d3b79d0e0..f13d852ab3c 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -433,6 +433,26 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) return 0; } +/** + * sysfs_pathname - return full path to sysfs dirent + * @sd: sysfs_dirent whose path we want + * @path: caller allocated buffer + * + * Gives the name "/" to the sysfs_root entry; any path returned + * is relative to wherever sysfs is mounted. + * + * XXX: does no error checking on @path size + */ +static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) +{ + if (sd->s_parent) { + sysfs_pathname(sd->s_parent, path); + strcat(path, "/"); + } + strcat(path, sd->s_name); + return path; +} + /** * sysfs_add_one - add sysfs_dirent to parent * @acxt: addrm context to use @@ -458,8 +478,16 @@ int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) int ret; ret = __sysfs_add_one(acxt, sd); - WARN(ret == -EEXIST, KERN_WARNING "sysfs: duplicate filename '%s' " - "can not be created\n", sd->s_name); + if (ret == -EEXIST) { + char *path = kzalloc(PATH_MAX, GFP_KERNEL); + WARN(1, KERN_WARNING + "sysfs: cannot create duplicate filename '%s'\n", + (path == NULL) ? sd->s_name : + strcat(strcat(sysfs_pathname(acxt->parent_sd, path), "/"), + sd->s_name)); + kfree(path); + } + return ret; } -- 2.41.1