linux/fs/proc/proc_devtree.c

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/*
* proc_devtree.c - handles /proc/device-tree
*
* Copyright 1997 Paul Mackerras
*/
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/of.h>
#include <linux/module.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <asm/prom.h>
#include <asm/uaccess.h>
#include "internal.h"
static inline void set_node_proc_entry(struct device_node *np,
struct proc_dir_entry *de)
{
#ifdef HAVE_ARCH_DEVTREE_FIXUPS
np->pde = de;
#endif
}
static struct proc_dir_entry *proc_device_tree;
/*
* Supply data on a read from /proc/device-tree/node/property.
*/
static int property_proc_show(struct seq_file *m, void *v)
{
struct property *pp = m->private;
seq_write(m, pp->value, pp->length);
return 0;
}
static int property_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, property_proc_show, PDE(inode)->data);
}
static const struct file_operations property_proc_fops = {
.owner = THIS_MODULE,
.open = property_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
/*
* For a node with a name like "gc@10", we make symlinks called "gc"
* and "@10" to it.
*/
/*
* Add a property to a node
*/
static struct proc_dir_entry *
__proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp,
const char *name)
{
struct proc_dir_entry *ent;
/*
* Unfortunately proc_register puts each new entry
* at the beginning of the list. So we rearrange them.
*/
ent = proc_create_data(name,
strncmp(name, "security-", 9) ? S_IRUGO : S_IRUSR,
de, &property_proc_fops, pp);
if (ent == NULL)
return NULL;
if (!strncmp(name, "security-", 9))
ent->size = 0; /* don't leak number of password chars */
else
ent->size = pp->length;
return ent;
}
void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop)
{
__proc_device_tree_add_prop(pde, prop, prop->name);
}
void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
struct property *prop)
{
remove_proc_entry(prop->name, pde);
}
void proc_device_tree_update_prop(struct proc_dir_entry *pde,
struct property *newprop,
struct property *oldprop)
{
struct proc_dir_entry *ent;
for (ent = pde->subdir; ent != NULL; ent = ent->next)
if (ent->data == oldprop)
break;
if (ent == NULL) {
printk(KERN_WARNING "device-tree: property \"%s\" "
" does not exist\n", oldprop->name);
} else {
ent->data = newprop;
ent->size = newprop->length;
}
}
/*
* Various dodgy firmware might give us nodes and/or properties with
* conflicting names. That's generally ok, except for exporting via /proc,
* so munge names here to ensure they're unique.
*/
static int duplicate_name(struct proc_dir_entry *de, const char *name)
{
struct proc_dir_entry *ent;
int found = 0;
spin_lock(&proc_subdir_lock);
for (ent = de->subdir; ent != NULL; ent = ent->next) {
if (strcmp(ent->name, name) == 0) {
found = 1;
break;
}
}
spin_unlock(&proc_subdir_lock);
return found;
}
static const char *fixup_name(struct device_node *np, struct proc_dir_entry *de,
const char *name)
{
char *fixed_name;
int fixup_len = strlen(name) + 2 + 1; /* name + #x + \0 */
int i = 1, size;
realloc:
fixed_name = kmalloc(fixup_len, GFP_KERNEL);
if (fixed_name == NULL) {
printk(KERN_ERR "device-tree: Out of memory trying to fixup "
"name \"%s\"\n", name);
return name;
}
retry:
size = snprintf(fixed_name, fixup_len, "%s#%d", name, i);
size++; /* account for NULL */
if (size > fixup_len) {
/* We ran out of space, free and reallocate. */
kfree(fixed_name);
fixup_len = size;
goto realloc;
}
if (duplicate_name(de, fixed_name)) {
/* Multiple duplicates. Retry with a different offset. */
i++;
goto retry;
}
printk(KERN_WARNING "device-tree: Duplicate name in %s, "
"renamed to \"%s\"\n", np->full_name, fixed_name);
return fixed_name;
}
/*
* Process a node, adding entries for its children and its properties.
*/
void proc_device_tree_add_node(struct device_node *np,
struct proc_dir_entry *de)
{
struct property *pp;
struct proc_dir_entry *ent;
struct device_node *child;
const char *p;
set_node_proc_entry(np, de);
for (child = NULL; (child = of_get_next_child(np, child));) {
/* Use everything after the last slash, or the full name */
p = strrchr(child->full_name, '/');
if (!p)
p = child->full_name;
else
++p;
if (duplicate_name(de, p))
p = fixup_name(np, de, p);
ent = proc_mkdir(p, de);
if (ent == NULL)
break;
proc_device_tree_add_node(child, ent);
}
of_node_put(child);
for (pp = np->properties; pp != NULL; pp = pp->next) {
p = pp->name;
if (strchr(p, '/'))
continue;
if (duplicate_name(de, p))
p = fixup_name(np, de, p);
ent = __proc_device_tree_add_prop(de, pp, p);
if (ent == NULL)
break;
}
}
/*
* Called on initialization to set up the /proc/device-tree subtree
*/
void __init proc_device_tree_init(void)
{
struct device_node *root;
proc_device_tree = proc_mkdir("device-tree", NULL);
if (proc_device_tree == NULL)
return;
root = of_find_node_by_path("/");
if (root == NULL) {
pr_debug("/proc/device-tree: can't find root\n");
return;
}
proc_device_tree_add_node(root, proc_device_tree);
of_node_put(root);
}