/*
* linux/fs/adfs/dir.c
*
* Copyright (C) 1999-2000 Russell King
*
* 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.
*
* Common directory handling for ADFS
*/
#include "adfs.h"
/*
* For future. This should probably be per-directory.
*/
static DEFINE_RWLOCK(adfs_dir_lock);
static int
adfs_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
struct object_info obj;
struct adfs_dir dir;
int ret = 0;
if (ctx->pos >> 32)
return 0;
ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
if (ret)
return ret;
if (ctx->pos == 0) {
if (!dir_emit_dot(file, ctx))
goto free_out;
ctx->pos = 1;
}
if (ctx->pos == 1) {
if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR))
goto free_out;
ctx->pos = 2;
}
read_lock(&adfs_dir_lock);
ret = ops->setpos(&dir, ctx->pos - 2);
if (ret)
goto unlock_out;
while (ops->getnext(&dir, &obj) == 0) {
if (!dir_emit(ctx, obj.name, obj.name_len,
obj.file_id, DT_UNKNOWN))
break;
ctx->pos++;
}
unlock_out:
read_unlock(&adfs_dir_lock);
free_out:
ops->free(&dir);
return ret;
}
int
adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait)
{
int ret = -EINVAL;
#ifdef CONFIG_ADFS_FS_RW
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
struct adfs_dir dir;
printk(KERN_INFO "adfs_dir_update: object %06X in dir %06X\n",
obj->file_id, obj->parent_id);
if (!ops->update) {
ret = -EINVAL;
goto out;
}
ret = ops->read(sb, obj->parent_id, 0, &dir);
if (ret)
goto out;
write_lock(&adfs_dir_lock);
ret = ops->update(&dir, obj);
write_unlock(&adfs_dir_lock);
if (wait) {
int err = ops->sync(&dir);
if (!ret)
ret = err;
}
ops->free(&dir);
out:
#endif
return ret;
}
static int
adfs_match(const struct qstr *name, struct object_info *obj)
{
int i;
if (name->len != obj->name_len)
return 0;
for (i = 0; i < name->len; i++) {
char c1, c2;
c1 = name->name[i];
c2 = obj->name[i];
if (c1 >= 'A' && c1 <= 'Z')
c1 += 'a' - 'A';
if (c2 >= 'A' && c2 <= 'Z')
c2 += 'a' - 'A';
if (c1 != c2)
return 0;
}
return 1;
}
static int
adfs_dir_lookup_byname(struct inode *inode, const struct qstr *name, struct object_info *obj)
{
struct super_block *sb = inode->i_sb;
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
struct adfs_dir dir;
int ret;
ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
if (ret)
goto out;
if (ADFS_I(inode)->parent_id != dir.parent_id) {
adfs_error(sb, "parent directory changed under me! (%lx but got %x)\n",
ADFS_I(inode)->parent_id, dir.parent_id);
ret = -EIO;
goto free_out;
}
obj->parent_id = inode->i_ino;
/*
* '.' is handled by reserved_lookup() in fs/namei.c
*/
if (name->len == 2 && name->name[0] == '.' && name->name[1] == '.') {
/*
* Currently unable to fill in the rest of 'obj',
* but this is better than nothing. We need to
* ascend one level to find it's parent.
*/
obj->name_len = 0;
obj->file_id = obj->parent_id;
goto free_out;
}
read_lock(&adfs_dir_lock);
ret = ops->setpos(&dir, 0);
if (ret)
goto unlock_out;
ret = -ENOENT;
while (ops->getnext(&dir, obj) == 0) {
if (adfs_match(name, obj)) {
ret = 0;
break;
}
}
unlock_out:
read_unlock(&adfs_dir_lock);
free_out:
ops->free(&dir);
out:
return ret;
}
const struct file_operations adfs_dir_operations = {
.read = generic_read_dir,
.llseek = generic_file_llseek,
.iterate = adfs_readdir,
.fsync = generic_file_fsync,
};
static int
adfs_hash(const struct dentry *parent, struct qstr *qstr)
{
const unsigned int name_len = ADFS_SB(parent->d_sb)->s_namelen;
const unsigned char *name;
unsigned long hash;
int i;
if (qstr->len < name_len)
return 0;
/*
* Truncate the name in place, avoids
* having to define a compare function.
*/
qstr->len = i = name_len;
name = qstr->name;
hash = init_name_hash(parent);
while (i--) {
char c;
c = *name++;
if (c >= 'A' && c <= 'Z')
c += 'a' - 'A';
hash = partial_name_hash(c, hash);
}
qstr->hash = end_name_hash(hash);
return 0;
}
/*
* Compare two names, taking note of the name length
* requirements of the underlying filesystem.
*/
static int
adfs_compare(const struct dentry *dentry,
unsigned int len, const char *str, const struct qstr *name)
{
int i;
if (len != name->len)
return 1;
for (i = 0; i < name->len; i++) {
char a, b;
a = str[i];
b = name->name[i];
if (a >= 'A' && a <= 'Z')
a += 'a' - 'A';
if (b >= 'A' && b <= 'Z')
b += 'a' - 'A';
if (a != b)
return 1;
}
return 0;
}
const struct dentry_operations adfs_dentry_operations = {
.d_hash = adfs_hash,
.d_compare = adfs_compare,
};
static struct dentry *
adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
struct inode *inode = NULL;
struct object_info obj;
int error;
error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj);
if (error == 0) {
error = -EACCES;
/*
* This only returns NULL if get_empty_inode
* fails.
*/
inode = adfs_iget(dir->i_sb, &obj);
if (inode)
error = 0;
}
d_add(dentry, inode);
return ERR_PTR(error);
}
/*
* directories can handle most operations...
*/
const struct inode_operations adfs_dir_inode_operations = {
.lookup = adfs_lookup,
.setattr = adfs_notify_change,
};
t/commit/tools/perf/tests/mmap-thread-lookup.c?h=nds-private-remove&id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
| tree | be6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /tools/perf/tests/mmap-thread-lookup.c |
|---|
| parent | 24c2503255d35c269b67162c397a1a1c1e02f6ce (diff) |
|---|
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.
Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.
Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.
Reported-by: Erik Veijola <erik.veijola@intel.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>