linux/arch/powerpc/platforms/pseries/reconfig.c

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/*
* pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
* Hotplug and Dynamic Logical Partitioning on RPA platforms).
*
* Copyright (C) 2005 Nathan Lynch
* Copyright (C) 2005 IBM Corporation
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/notifier.h>
#include <linux/proc_fs.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 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/of.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/uaccess.h>
#include <asm/mmu.h>
/**
* derive_parent - basically like dirname(1)
* @path: the full_name of a node to be added to the tree
*
* Returns the node which should be the parent of the node
* described by path. E.g., for path = "/foo/bar", returns
* the node with full_name = "/foo".
*/
static struct device_node *derive_parent(const char *path)
{
struct device_node *parent = NULL;
char *parent_path = "/";
size_t parent_path_len = strrchr(path, '/') - path + 1;
/* reject if path is "/" */
if (!strcmp(path, "/"))
return ERR_PTR(-EINVAL);
if (strrchr(path, '/') != path) {
parent_path = kmalloc(parent_path_len, GFP_KERNEL);
if (!parent_path)
return ERR_PTR(-ENOMEM);
strlcpy(parent_path, path, parent_path_len);
}
parent = of_find_node_by_path(parent_path);
if (!parent)
return ERR_PTR(-EINVAL);
if (strcmp(parent_path, "/"))
kfree(parent_path);
return parent;
}
static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
{
struct device_node *np;
int err = -ENOMEM;
np = kzalloc(sizeof(*np), GFP_KERNEL);
if (!np)
goto out_err;
np->full_name = kstrdup(path, GFP_KERNEL);
if (!np->full_name)
goto out_err;
np->properties = proplist;
of_node_set_flag(np, OF_DYNAMIC);
kref_init(&np->kref);
np->parent = derive_parent(path);
if (IS_ERR(np->parent)) {
err = PTR_ERR(np->parent);
goto out_err;
}
err = of_attach_node(np);
if (err) {
printk(KERN_ERR "Failed to add device node %s\n", path);
goto out_err;
}
of_node_put(np->parent);
return 0;
out_err:
if (np) {
of_node_put(np->parent);
kfree(np->full_name);
kfree(np);
}
return err;
}
static int pSeries_reconfig_remove_node(struct device_node *np)
{
struct device_node *parent, *child;
parent = of_get_parent(np);
if (!parent)
return -EINVAL;
if ((child = of_get_next_child(np, NULL))) {
of_node_put(child);
of_node_put(parent);
return -EBUSY;
}
of_detach_node(np);
of_node_put(parent);
of_node_put(np); /* Must decrement the refcount */
return 0;
}
/*
* /proc/powerpc/ofdt - yucky binary interface for adding and removing
* OF device nodes. Should be deprecated as soon as we get an
* in-kernel wrapper for the RTAS ibm,configure-connector call.
*/
static void release_prop_list(const struct property *prop)
{
struct property *next;
for (; prop; prop = next) {
next = prop->next;
kfree(prop->name);
kfree(prop->value);
kfree(prop);
}
}
/**
* parse_next_property - process the next property from raw input buffer
* @buf: input buffer, must be nul-terminated
* @end: end of the input buffer + 1, for validation
* @name: return value; set to property name in buf
* @length: return value; set to length of value
* @value: return value; set to the property value in buf
*
* Note that the caller must make copies of the name and value returned,
* this function does no allocation or copying of the data. Return value
* is set to the next name in buf, or NULL on error.
*/
static char * parse_next_property(char *buf, char *end, char **name, int *length,
unsigned char **value)
{
char *tmp;
*name = buf;
tmp = strchr(buf, ' ');
if (!tmp) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
*tmp = '\0';
if (++tmp >= end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
/* now we're on the length */
*length = -1;
*length = simple_strtoul(tmp, &tmp, 10);
if (*length == -1) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
if (*tmp != ' ' || ++tmp >= end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
/* now we're on the value */
*value = tmp;
tmp += *length;
if (tmp > end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__func__, __LINE__);
return NULL;
}
tmp++;
/* and now we should be on the next name, or the end */
return tmp;
}
static struct property *new_property(const char *name, const int length,
const unsigned char *value, struct property *last)
{
struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);
if (!new)
return NULL;
if (!(new->name = kmalloc(strlen(name) + 1, GFP_KERNEL)))
goto cleanup;
if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
goto cleanup;
strcpy(new->name, name);
memcpy(new->value, value, length);
*(((char *)new->value) + length) = 0;
new->length = length;
new->next = last;
return new;
cleanup:
kfree(new->name);
kfree(new->value);
kfree(new);
return NULL;
}
static int do_add_node(char *buf, size_t bufsize)
{
char *path, *end, *name;
struct device_node *np;
struct property *prop = NULL;
unsigned char* value;
int length, rv = 0;
end = buf + bufsize;
path = buf;
buf = strchr(buf, ' ');
if (!buf)
return -EINVAL;
*buf = '\0';
buf++;
if ((np = of_find_node_by_path(path))) {
of_node_put(np);
return -EINVAL;
}
/* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
while (buf < end &&
(buf = parse_next_property(buf, end, &name, &length, &value))) {
struct property *last = prop;
prop = new_property(name, length, value, last);
if (!prop) {
rv = -ENOMEM;
prop = last;
goto out;
}
}
if (!buf) {
rv = -EINVAL;
goto out;
}
rv = pSeries_reconfig_add_node(path, prop);
out:
if (rv)
release_prop_list(prop);
return rv;
}
static int do_remove_node(char *buf)
{
struct device_node *node;
int rv = -ENODEV;
if ((node = of_find_node_by_path(buf)))
rv = pSeries_reconfig_remove_node(node);
of_node_put(node);
return rv;
}
static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
{
char *handle_str;
phandle handle;
*npp = NULL;
handle_str = buf;
buf = strchr(buf, ' ');
if (!buf)
return NULL;
*buf = '\0';
buf++;
handle = simple_strtoul(handle_str, NULL, 0);
*npp = of_find_node_by_phandle(handle);
return buf;
}
static int do_add_property(char *buf, size_t bufsize)
{
struct property *prop = NULL;
struct device_node *np;
unsigned char *value;
char *name, *end;
int length;
end = buf + bufsize;
buf = parse_node(buf, bufsize, &np);
if (!np)
return -ENODEV;
if (parse_next_property(buf, end, &name, &length, &value) == NULL)
return -EINVAL;
prop = new_property(name, length, value, NULL);
if (!prop)
return -ENOMEM;
prom_add_property(np, prop);
return 0;
}
static int do_remove_property(char *buf, size_t bufsize)
{
struct device_node *np;
char *tmp;
struct property *prop;
buf = parse_node(buf, bufsize, &np);
if (!np)
return -ENODEV;
tmp = strchr(buf,' ');
if (tmp)
*tmp = '\0';
if (strlen(buf) == 0)
return -EINVAL;
prop = of_find_property(np, buf, NULL);
return prom_remove_property(np, prop);
}
static int do_update_property(char *buf, size_t bufsize)
{
struct device_node *np;
unsigned char *value;
char *name, *end, *next_prop;
int length;
struct property *newprop;
buf = parse_node(buf, bufsize, &np);
end = buf + bufsize;
if (!np)
return -ENODEV;
next_prop = parse_next_property(buf, end, &name, &length, &value);
if (!next_prop)
return -EINVAL;
if (!strlen(name))
return -ENODEV;
newprop = new_property(name, length, value, NULL);
if (!newprop)
return -ENOMEM;
if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
slb_set_size(*(int *)value);
return prom_update_property(np, newprop);
}
/**
* ofdt_write - perform operations on the Open Firmware device tree
*
* @file: not used
* @buf: command and arguments
* @count: size of the command buffer
* @off: not used
*
* Operations supported at this time are addition and removal of
* whole nodes along with their properties. Operations on individual
* properties are not implemented (yet).
*/
static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
loff_t *off)
{
int rv = 0;
char *kbuf;
char *tmp;
if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
rv = -ENOMEM;
goto out;
}
if (copy_from_user(kbuf, buf, count)) {
rv = -EFAULT;
goto out;
}
kbuf[count] = '\0';
tmp = strchr(kbuf, ' ');
if (!tmp) {
rv = -EINVAL;
goto out;
}
*tmp = '\0';
tmp++;
if (!strcmp(kbuf, "add_node"))
rv = do_add_node(tmp, count - (tmp - kbuf));
else if (!strcmp(kbuf, "remove_node"))
rv = do_remove_node(tmp);
else if (!strcmp(kbuf, "add_property"))
rv = do_add_property(tmp, count - (tmp - kbuf));
else if (!strcmp(kbuf, "remove_property"))
rv = do_remove_property(tmp, count - (tmp - kbuf));
else if (!strcmp(kbuf, "update_property"))
rv = do_update_property(tmp, count - (tmp - kbuf));
else
rv = -EINVAL;
out:
kfree(kbuf);
return rv ? rv : count;
}
static const struct file_operations ofdt_fops = {
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-16 00:52:59 +08:00
.write = ofdt_write,
.llseek = noop_llseek,
};
/* create /proc/powerpc/ofdt write-only by root */
static int proc_ppc64_create_ofdt(void)
{
struct proc_dir_entry *ent;
if (!machine_is(pseries))
return 0;
ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
if (ent)
ent->size = 0;
return 0;
}
__initcall(proc_ppc64_create_ofdt);