From 4a520d2769beb736ba2bd084b8293ce148a1a7ae Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 12 Apr 2013 14:06:01 +0100 Subject: [PATCH] proc: Supply an accessor for getting the data from a PDE's parent Supply an accessor function for getting the private data from the parent proc_dir_entry struct of the proc_dir_entry struct associated with an inode. ReiserFS, for instance, stores the super_block pointer in the proc directory it makes for that super_block, and a pointer to the respective seq_file show function in each of the proc files in that directory. This allows a reduction in the number of file_operations structs, open functions and seq_operations structs required. The problem otherwise is that each show function requires two pieces of data but only has storage for one per PDE (and this has no release function). Signed-off-by: David Howells Acked-by: Mauro Carvalho Chehab Acked-by: Greg Kroah-Hartman cc: Jerry Chuang cc: Maxim Mikityanskiy cc: YAMANE Toshiaki cc: linux-wireless@vger.kernel.org cc: linux-scsi@vger.kernel.org cc: devel@driverdev.osuosl.org Signed-off-by: Al Viro --- drivers/scsi/megaraid.c | 2 +- drivers/staging/rtl8187se/r8180_core.c | 2 +- drivers/staging/rtl8192u/r8192U_core.c | 2 +- fs/proc/generic.c | 7 +++++++ include/linux/proc_fs.h | 1 + 5 files changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c index ef3384d39e11..7373255aa1e8 100644 --- a/drivers/scsi/megaraid.c +++ b/drivers/scsi/megaraid.c @@ -2760,7 +2760,7 @@ proc_show_rdrv_40(struct seq_file *m, void *v) */ static int mega_proc_open(struct inode *inode, struct file *file) { - adapter_t *adapter = PDE(inode)->parent->data; + adapter_t *adapter = proc_get_parent_data(inode); int (*show)(struct seq_file *, void *) = PDE_DATA(inode); return single_open(file, show, adapter); diff --git a/drivers/staging/rtl8187se/r8180_core.c b/drivers/staging/rtl8187se/r8180_core.c index ab469ceae88c..f7c1d9905ec6 100644 --- a/drivers/staging/rtl8187se/r8180_core.c +++ b/drivers/staging/rtl8187se/r8180_core.c @@ -296,7 +296,7 @@ void rtl8180_proc_remove_one(struct net_device *dev) */ static int rtl8180_proc_open(struct inode *inode, struct file *file) { - struct net_device *dev = PDE(inode)->parent->data; + struct net_device *dev = proc_get_parent_data(inode); int (*show)(struct seq_file *, void *) = PDE_DATA(inode); return single_open(file, show, dev); diff --git a/drivers/staging/rtl8192u/r8192U_core.c b/drivers/staging/rtl8192u/r8192U_core.c index 27ba2a3111d2..145923397556 100644 --- a/drivers/staging/rtl8192u/r8192U_core.c +++ b/drivers/staging/rtl8192u/r8192U_core.c @@ -637,7 +637,7 @@ void rtl8192_proc_module_remove(void) */ static int rtl8192_proc_open(struct inode *inode, struct file *file) { - struct net_device *dev = PDE(inode)->parent->data; + struct net_device *dev = proc_get_parent_data(inode); int (*show)(struct seq_file *, void *) = PDE_DATA(inode); return single_open(file, show, dev); diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 4074da57c99e..75e08d36b2f1 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -617,3 +617,10 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) return 0; } EXPORT_SYMBOL(remove_proc_subtree); + +void *proc_get_parent_data(const struct inode *inode) +{ + struct proc_dir_entry *de = PDE(inode); + return de->parent->data; +} +EXPORT_SYMBOL_GPL(proc_get_parent_data); diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index a0fb1c2f1d8e..bae820742341 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -86,6 +86,7 @@ static inline struct proc_dir_entry *proc_create(const char *name, umode_t mode, extern void proc_set_size(struct proc_dir_entry *, loff_t); extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t); +extern void *proc_get_parent_data(const struct inode *); #else static inline void proc_flush_task(struct task_struct *task)