blob: bed05b644c2c548693dc43a43260450fe699d4cd [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* SPU file system
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
*
* Author: Arnd Bergmann <arndb@de.ibm.com>
*/
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/fs_context.h>
#include <linux/fs_parser.h>
#include <linux/fsnotify.h>
#include <linux/backing-dev.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/pagemap.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <asm/prom.h>
#include <asm/spu.h>
#include <asm/spu_priv1.h>
#include <linux/uaccess.h>
#include "spufs.h"
struct spufs_sb_info {
bool debug;
};
static struct kmem_cache *spufs_inode_cache;
char *isolated_loader;
static int isolated_loader_size;
static struct spufs_sb_info *spufs_get_sb_info(struct super_block *sb)
{
return sb->s_fs_info;
}
static struct inode *
spufs_alloc_inode(struct super_block *sb)
{
struct spufs_inode_info *ei;
ei = kmem_cache_alloc(spufs_inode_cache, GFP_KERNEL);
if (!ei)
return NULL;
ei->i_gang = NULL;
ei->i_ctx = NULL;
ei->i_openers = 0;
return &ei->vfs_inode;
}
static void spufs_free_inode(struct inode *inode)
{
kmem_cache_free(spufs_inode_cache, SPUFS_I(inode));
}
static void
spufs_init_once(void *p)
{
struct spufs_inode_info *ei = p;
inode_init_once(&ei->vfs_inode);
}
static struct inode *
spufs_new_inode(struct super_block *sb, umode_t mode)
{
struct inode *inode;
inode = new_inode(sb);
if (!inode)
goto out;
inode->i_ino = get_next_ino();
inode->i_mode = mode;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
out:
return inode;
}
static int
spufs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
struct iattr *attr)
{
struct inode *inode = d_inode(dentry);
if ((attr->ia_valid & ATTR_SIZE) &&
(attr->ia_size != inode->i_size))
return -EINVAL;
setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
static int
spufs_new_file(struct super_block *sb, struct dentry *dentry,
const struct file_operations *fops, umode_t mode,
size_t size, struct spu_context *ctx)
{
static const struct inode_operations spufs_file_iops = {
.setattr = spufs_setattr,
};
struct inode *inode;
int ret;
ret = -ENOSPC;
inode = spufs_new_inode(sb, S_IFREG | mode);
if (!inode)
goto out;
ret = 0;
inode->i_op = &spufs_file_iops;
inode->i_fop = fops;
inode->i_size = size;
inode->i_private = SPUFS_I(inode)->i_ctx = get_spu_context(ctx);
d_add(dentry, inode);
out:
return ret;
}
static void
spufs_evict_inode(struct inode *inode)
{
struct spufs_inode_info *ei = SPUFS_I(inode);
clear_inode(inode);
if (ei->i_ctx)
put_spu_context(ei->i_ctx);
if (ei->i_gang)
put_spu_gang(ei->i_gang);
}
static void spufs_prune_dir(struct dentry *dir)
{
struct dentry *dentry, *tmp;
inode_lock(d_inode(dir));
list_for_each_entry_safe(dentry, tmp, &dir->d_subdirs, d_child) {
spin_lock(&dentry->d_lock);
if (simple_positive(dentry)) {
dget_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
simple_unlink(d_inode(dir), dentry);
/* XXX: what was dcache_lock protecting here? Other
* filesystems (IB, configfs) release dcache_lock
* before unlink */
dput(dentry);
} else {
spin_unlock(&dentry->d_lock);
}
}
shrink_dcache_parent(dir);
inode_unlock(d_inode(dir));
}
/* Caller must hold parent->i_mutex */
static int spufs_rmdir(struct inode *parent, struct dentry *dir)
{
/* remove all entries */
int res;
spufs_prune_dir(dir);
d_drop(dir);
res = simple_rmdir(parent, dir);
/* We have to give up the mm_struct */
spu_forget(SPUFS_I(d_inode(dir))->i_ctx);
return res;
}
static int spufs_fill_dir(struct dentry *dir,
const struct spufs_tree_descr *files, umode_t mode,
struct spu_context *ctx)
{
while (files->name && files->name[0]) {
int ret;
struct dentry *dentry = d_alloc_name(dir, files->name);
if (!dentry)
return -ENOMEM;
ret = spufs_new_file(dir->d_sb, dentry, files->ops,
files->mode & mode, files->size, ctx);
if (ret)
return ret;
files++;
}
return 0;
}
static int spufs_dir_close(struct inode *inode, struct file *file)
{
struct inode *parent;
struct dentry *dir;
int ret;
dir = file->f_path.dentry;
parent = d_inode(dir->d_parent);
inode_lock_nested(parent, I_MUTEX_PARENT);
ret = spufs_rmdir(parent, dir);
inode_unlock(parent);
WARN_ON(ret);
return dcache_dir_close(inode, file);
}
const struct file_operations spufs_context_fops = {
.open = dcache_dir_open,
.release = spufs_dir_close,
.llseek = dcache_dir_lseek,
.read = generic_read_dir,
.iterate_shared = dcache_readdir,
.fsync = noop_fsync,
};
EXPORT_SYMBOL_GPL(spufs_context_fops);
static int
spufs_mkdir(struct inode *dir, struct dentry *dentry, unsigned int flags,
umode_t mode)
{
int ret;
struct inode *inode;
struct spu_context *ctx;
inode = spufs_new_inode(dir->i_sb, mode | S_IFDIR);
if (!inode)
return -ENOSPC;
inode_init_owner(&init_user_ns, inode, dir, mode | S_IFDIR);
ctx = alloc_spu_context(SPUFS_I(dir)->i_gang); /* XXX gang */
SPUFS_I(inode)->i_ctx = ctx;
if (!ctx) {
iput(inode);
return -ENOSPC;
}
ctx->flags = flags;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
inode_lock(inode);
dget(dentry);
inc_nlink(dir);
inc_nlink(inode);
d_instantiate(dentry, inode);
if (flags & SPU_CREATE_NOSCHED)
ret = spufs_fill_dir(dentry, spufs_dir_nosched_contents,
mode, ctx);
else
ret = spufs_fill_dir(dentry, spufs_dir_contents, mode, ctx);
if (!ret && spufs_get_sb_info(dir->i_sb)->debug)
ret = spufs_fill_dir(dentry, spufs_dir_debug_contents,
mode, ctx);
if (ret)
spufs_rmdir(dir, dentry);
inode_unlock(inode);
return ret;
}
static int spufs_context_open(struct path *path)
{
int ret;
struct file *filp;
ret = get_unused_fd_flags(0);
if (ret < 0)
return ret;
filp = dentry_open(path, O_RDONLY, current_cred());
if (IS_ERR(filp)) {
put_unused_fd(ret);
return PTR_ERR(filp);
}
filp->f_op = &spufs_context_fops;
fd_install(ret, filp);
return ret;
}
static struct spu_context *
spufs_assert_affinity(unsigned int flags, struct spu_gang *gang,
struct file *filp)
{
struct spu_context *tmp, *neighbor, *err;
int count, node;
int aff_supp;
aff_supp = !list_empty(&(list_entry(cbe_spu_info[0].spus.next,
struct spu, cbe_list))->aff_list);
if (!aff_supp)
return ERR_PTR(-EINVAL);
if (flags & SPU_CREATE_GANG)
return ERR_PTR(-EINVAL);
if (flags & SPU_CREATE_AFFINITY_MEM &&
gang->aff_ref_ctx &&
gang->aff_ref_ctx->flags & SPU_CREATE_AFFINITY_MEM)
return ERR_PTR(-EEXIST);
if (gang->aff_flags & AFF_MERGED)
return ERR_PTR(-EBUSY);
neighbor = NULL;
if (flags & SPU_CREATE_AFFINITY_SPU) {
if (!filp || filp->f_op != &spufs_context_fops)
return ERR_PTR(-EINVAL);
neighbor = get_spu_context(
SPUFS_I(file_inode(filp))->i_ctx);
if (!list_empty(&neighbor->aff_list) && !(neighbor->aff_head) &&
!list_is_last(&neighbor->aff_list, &gang->aff_list_head) &&
!list_entry(neighbor->aff_list.next, struct spu_context,
aff_list)->aff_head) {
err = ERR_PTR(-EEXIST);
goto out_put_neighbor;
}
if (gang != neighbor->gang) {
err = ERR_PTR(-EINVAL);
goto out_put_neighbor;
}
count = 1;
list_for_each_entry(tmp, &gang->aff_list_head, aff_list)
count++;
if (list_empty(&neighbor->aff_list))
count++;
for (node = 0; node < MAX_NUMNODES; node++) {
if ((cbe_spu_info[node].n_spus - atomic_read(
&cbe_spu_info[node].reserved_spus)) >= count)
break;
}
if (node == MAX_NUMNODES) {
err = ERR_PTR(-EEXIST);
goto out_put_neighbor;
}
}
return neighbor;
out_put_neighbor:
put_spu_context(neighbor);
return err;
}
static void
spufs_set_affinity(unsigned int flags, struct spu_context *ctx,
struct spu_context *neighbor)
{
if (flags & SPU_CREATE_AFFINITY_MEM)
ctx->gang->aff_ref_ctx = ctx;
if (flags & SPU_CREATE_AFFINITY_SPU) {
if (list_empty(&neighbor->aff_list)) {
list_add_tail(&neighbor->aff_list,
&ctx->gang->aff_list_head);
neighbor->aff_head = 1;
}
if (list_is_last(&neighbor->aff_list, &ctx->gang->aff_list_head)
|| list_entry(neighbor->aff_list.next, struct spu_context,
aff_list)->aff_head) {
list_add(&ctx->aff_list, &neighbor->aff_list);
} else {
list_add_tail(&ctx->aff_list, &neighbor->aff_list);
if (neighbor->aff_head) {
neighbor->aff_head = 0;
ctx->aff_head = 1;
}
}
if (!ctx->gang->aff_ref_ctx)
ctx->gang->aff_ref_ctx = ctx;
}
}
static int
spufs_create_context(struct inode *inode, struct dentry *dentry,
struct vfsmount *mnt, int flags, umode_t mode,
struct file *aff_filp)
{
int ret;
int affinity;
struct spu_gang *gang;
struct spu_context *neighbor;
struct path path = {.mnt = mnt, .dentry = dentry};
if ((flags & SPU_CREATE_NOSCHED) &&
!capable(CAP_SYS_NICE))
return -EPERM;
if ((flags & (SPU_CREATE_NOSCHED | SPU_CREATE_ISOLATE))
== SPU_CREATE_ISOLATE)
return -EINVAL;
if ((flags & SPU_CREATE_ISOLATE) && !isolated_loader)
return -ENODEV;
gang = NULL;
neighbor = NULL;
affinity = flags & (SPU_CREATE_AFFINITY_MEM | SPU_CREATE_AFFINITY_SPU);
if (affinity) {
gang = SPUFS_I(inode)->i_gang;
if (!gang)
return -EINVAL;
mutex_lock(&gang->aff_mutex);
neighbor = spufs_assert_affinity(flags, gang, aff_filp);
if (IS_ERR(neighbor)) {
ret = PTR_ERR(neighbor);
goto out_aff_unlock;
}
}
ret = spufs_mkdir(inode, dentry, flags, mode & 0777);
if (ret)
goto out_aff_unlock;
if (affinity) {
spufs_set_affinity(flags, SPUFS_I(d_inode(dentry))->i_ctx,
neighbor);
if (neighbor)
put_spu_context(neighbor);
}
ret = spufs_context_open(&path);
if (ret < 0)
WARN_ON(spufs_rmdir(inode, dentry));
out_aff_unlock:
if (affinity)
mutex_unlock(&gang->aff_mutex);
return ret;
}
static int
spufs_mkgang(struct inode *dir, struct dentry *dentry, umode_t mode)
{
int ret;
struct inode *inode;
struct spu_gang *gang;
ret = -ENOSPC;
inode = spufs_new_inode(dir->i_sb, mode | S_IFDIR);
if (!inode)
goto out;
ret = 0;
inode_init_owner(&init_user_ns, inode, dir, mode | S_IFDIR);
gang = alloc_spu_gang();
SPUFS_I(inode)->i_ctx = NULL;
SPUFS_I(inode)->i_gang = gang;
if (!gang) {
ret = -ENOMEM;
goto out_iput;
}
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
d_instantiate(dentry, inode);
inc_nlink(dir);
inc_nlink(d_inode(dentry));
return ret;
out_iput:
iput(inode);
out:
return ret;
}
static int spufs_gang_open(struct path *path)
{
int ret;
struct file *filp;
ret = get_unused_fd_flags(0);
if (ret < 0)
return ret;
/*
* get references for dget and mntget, will be released
* in error path of *_open().
*/
filp = dentry_open(path, O_RDONLY, current_cred());
if (IS_ERR(filp)) {
put_unused_fd(ret);
return PTR_ERR(filp);
}
filp->f_op = &simple_dir_operations;
fd_install(ret, filp);
return ret;
}
static int spufs_create_gang(struct inode *inode,
struct dentry *dentry,
struct vfsmount *mnt, umode_t mode)
{
struct path path = {.mnt = mnt, .dentry = dentry};
int ret;
ret = spufs_mkgang(inode, dentry, mode & 0777);
if (!ret) {
ret = spufs_gang_open(&path);
if (ret < 0) {
int err = simple_rmdir(inode, dentry);
WARN_ON(err);
}
}
return ret;
}
static struct file_system_type spufs_type;
long spufs_create(struct path *path, struct dentry *dentry,
unsigned int flags, umode_t mode, struct file *filp)
{
struct inode *dir = d_inode(path->dentry);
int ret;
/* check if we are on spufs */
if (path->dentry->d_sb->s_type != &spufs_type)
return -EINVAL;
/* don't accept undefined flags */
if (flags & (~SPU_CREATE_FLAG_ALL))
return -EINVAL;
/* only threads can be underneath a gang */
if (path->dentry != path->dentry->d_sb->s_root)
if ((flags & SPU_CREATE_GANG) || !SPUFS_I(dir)->i_gang)
return -EINVAL;
mode &= ~current_umask();
if (flags & SPU_CREATE_GANG)
ret = spufs_create_gang(dir, dentry, path->mnt, mode);
else
ret = spufs_create_context(dir, dentry, path->mnt, flags, mode,
filp);
if (ret >= 0)
fsnotify_mkdir(dir, dentry);
return ret;
}
/* File system initialization */
struct spufs_fs_context {
kuid_t uid;
kgid_t gid;
umode_t mode;
};
enum {
Opt_uid, Opt_gid, Opt_mode, Opt_debug,
};
static const struct fs_parameter_spec spufs_fs_parameters[] = {
fsparam_u32 ("gid", Opt_gid),
fsparam_u32oct ("mode", Opt_mode),
fsparam_u32 ("uid", Opt_uid),
fsparam_flag ("debug", Opt_debug),
{}
};
static int spufs_show_options(struct seq_file *m, struct dentry *root)
{
struct spufs_sb_info *sbi = spufs_get_sb_info(root->d_sb);
struct inode *inode = root->d_inode;
if (!uid_eq(inode->i_uid, GLOBAL_ROOT_UID))
seq_printf(m, ",uid=%u",
from_kuid_munged(&init_user_ns, inode->i_uid));
if (!gid_eq(inode->i_gid, GLOBAL_ROOT_GID))
seq_printf(m, ",gid=%u",
from_kgid_munged(&init_user_ns, inode->i_gid));
if ((inode->i_mode & S_IALLUGO) != 0775)
seq_printf(m, ",mode=%o", inode->i_mode);
if (sbi->debug)
seq_puts(m, ",debug");
return 0;
}
static int spufs_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
struct spufs_fs_context *ctx = fc->fs_private;
struct spufs_sb_info *sbi = fc->s_fs_info;
struct fs_parse_result result;
kuid_t uid;
kgid_t gid;
int opt;
opt = fs_parse(fc, spufs_fs_parameters, param, &result);
if (opt < 0)
return opt;
switch (opt) {
case Opt_uid:
uid = make_kuid(current_user_ns(), result.uint_32);
if (!uid_valid(uid))
return invalf(fc, "Unknown uid");
ctx->uid = uid;
break;
case Opt_gid:
gid = make_kgid(current_user_ns(), result.uint_32);
if (!gid_valid(gid))
return invalf(fc, "Unknown gid");
ctx->gid = gid;
break;
case Opt_mode:
ctx->mode = result.uint_32 & S_IALLUGO;
break;
case Opt_debug:
sbi->debug = true;
break;
}
return 0;
}
static void spufs_exit_isolated_loader(void)
{
free_pages((unsigned long) isolated_loader,
get_order(isolated_loader_size));
}
static void
spufs_init_isolated_loader(void)
{
struct device_node *dn;
const char *loader;
int size;
dn = of_find_node_by_path("/spu-isolation");
if (!dn)
return;
loader = of_get_property(dn, "loader", &size);
if (!loader)
return;
/* the loader must be align on a 16 byte boundary */
isolated_loader = (char *)__get_free_pages(GFP_KERNEL, get_order(size));
if (!isolated_loader)
return;
isolated_loader_size = size;
memcpy(isolated_loader, loader, size);
printk(KERN_INFO "spufs: SPU isolation mode enabled\n");
}
static int spufs_create_root(struct super_block *sb, struct fs_context *fc)
{
struct spufs_fs_context *ctx = fc->fs_private;
struct inode *inode;
if (!spu_management_ops)
return -ENODEV;
inode = spufs_new_inode(sb, S_IFDIR | ctx->mode);
if (!inode)
return -ENOMEM;
inode->i_uid = ctx->uid;
inode->i_gid = ctx->gid;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
SPUFS_I(inode)->i_ctx = NULL;
inc_nlink(inode);
sb->s_root = d_make_root(inode);
if (!sb->s_root)
return -ENOMEM;
return 0;
}
static const struct super_operations spufs_ops = {
.alloc_inode = spufs_alloc_inode,
.free_inode = spufs_free_inode,
.statfs = simple_statfs,
.evict_inode = spufs_evict_inode,
.show_options = spufs_show_options,
};
static int spufs_fill_super(struct super_block *sb, struct fs_context *fc)
{
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_blocksize = PAGE_SIZE;
sb->s_blocksize_bits = PAGE_SHIFT;
sb->s_magic = SPUFS_MAGIC;
sb->s_op = &spufs_ops;
return spufs_create_root(sb, fc);
}
static int spufs_get_tree(struct fs_context *fc)
{
return get_tree_single(fc, spufs_fill_super);
}
static void spufs_free_fc(struct fs_context *fc)
{
kfree(fc->s_fs_info);
}
static const struct fs_context_operations spufs_context_ops = {
.free = spufs_free_fc,
.parse_param = spufs_parse_param,
.get_tree = spufs_get_tree,
};
static int spufs_init_fs_context(struct fs_context *fc)
{
struct spufs_fs_context *ctx;
struct spufs_sb_info *sbi;
ctx = kzalloc(sizeof(struct spufs_fs_context), GFP_KERNEL);
if (!ctx)
goto nomem;
sbi = kzalloc(sizeof(struct spufs_sb_info), GFP_KERNEL);
if (!sbi)
goto nomem_ctx;
ctx->uid = current_uid();
ctx->gid = current_gid();
ctx->mode = 0755;
fc->fs_private = ctx;
fc->s_fs_info = sbi;
fc->ops = &spufs_context_ops;
return 0;
nomem_ctx:
kfree(ctx);
nomem:
return -ENOMEM;
}
static struct file_system_type spufs_type = {
.owner = THIS_MODULE,
.name = "spufs",
.init_fs_context = spufs_init_fs_context,
.parameters = spufs_fs_parameters,
.kill_sb = kill_litter_super,
};
MODULE_ALIAS_FS("spufs");
static int __init spufs_init(void)
{
int ret;
ret = -ENODEV;
if (!spu_management_ops)
goto out;
ret = -ENOMEM;
spufs_inode_cache = kmem_cache_create("spufs_inode_cache",
sizeof(struct spufs_inode_info), 0,
SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT, spufs_init_once);
if (!spufs_inode_cache)
goto out;
ret = spu_sched_init();
if (ret)
goto out_cache;
ret = register_spu_syscalls(&spufs_calls);
if (ret)
goto out_sched;
ret = register_filesystem(&spufs_type);
if (ret)
goto out_syscalls;
spufs_init_isolated_loader();
return 0;
out_syscalls:
unregister_spu_syscalls(&spufs_calls);
out_sched:
spu_sched_exit();
out_cache:
kmem_cache_destroy(spufs_inode_cache);
out:
return ret;
}
module_init(spufs_init);
static void __exit spufs_exit(void)
{
spu_sched_exit();
spufs_exit_isolated_loader();
unregister_spu_syscalls(&spufs_calls);
unregister_filesystem(&spufs_type);
kmem_cache_destroy(spufs_inode_cache);
}
module_exit(spufs_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");