fpgafs/inode.c

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7.5 KiB
C
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/*********************************************
* Benjamin Krill <ben@codiert.org>
*********************************************/
#include <linux/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include "fpgafs.h"
static struct inode *fpgafs_alloc_inode(struct super_block *sb);
static void fpgafs_destroy_inode(struct inode *inode);
static void fpgafs_delete_inode(struct inode *inode);
static struct inode *fpgafs_new_inode(struct super_block *sb, int mode);
static void fpgafs_prune_dir(struct dentry *dir);
int fpgafs_mkdir(struct inode *dir, struct dentry *dentry, int mode);
static int fpgafs_rmdir(struct inode *dir, struct dentry *dentry);
static int fpgafs_new_file(struct super_block *sb, struct dentry *dentry,
const struct file_operations *fops, int mode,
struct fpga_context *ctx);
static int fpgafs_setattr(struct dentry *dentry, struct iattr *attr);
const struct file_operations fpgafs_context_foperations = {
.open = dcache_dir_open,
//.release = fpgafs_dir_close,
.llseek = dcache_dir_lseek,
.read = generic_read_dir,
.readdir = dcache_readdir,
.fsync = simple_sync_file,
};
const struct inode_operations fpgafs_simple_dir_inode_operations = {
.lookup = simple_lookup
};
const struct inode_operations fpgafs_dir_inode_operations = {
.lookup = simple_lookup,
.mkdir = fpgafs_mkdir,
.rmdir = fpgafs_rmdir
};
static struct kmem_cache *fpgafs_inode_cache;
/* basic inode operations */
static struct inode *fpgafs_alloc_inode(struct super_block *sb)
{
struct fpgafs_inode_info *fsi;
fsi = kmem_cache_alloc(fpgafs_inode_cache, GFP_KERNEL);
if (!fsi)
return NULL;
fsi->i_ctx = NULL;
return &fsi->vfs_inode;
}
static void fpgafs_destroy_inode(struct inode *inode)
{
kmem_cache_free(fpgafs_inode_cache, FPGAFS_I(inode));
}
static void fpgafs_delete_inode(struct inode *inode)
{
//struct fpgafs_inode_info *fsi = FPGAFS_I(inode);
// XXX: do some fpga interface operations....
// if (fsi->i_ctx)
// put_fpga_context(ei->i_ctx);
clear_inode(inode);
}
static struct inode *fpgafs_new_inode(struct super_block *sb, int mode)
{
struct inode *inode;
inode = new_inode(sb);
if (!inode)
return inode;
inode->i_mode = mode;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
return inode;
}
/* FPGA FS specific functions */
static int fpgafs_fill_dir(struct dentry *dir, struct tree_descr *files,
int mode, struct fpga_context *ctx)
{
struct dentry *dentry;
int ret;
while (files->name && files->name[0]) {
ret = -ENOMEM;
dentry = d_alloc_name(dir, files->name);
if (!dentry)
goto out;
ret = fpgafs_new_file(dir->d_sb, dentry, files->ops,
files->mode & mode, ctx);
if (ret)
goto out;
files++;
}
return 0;
out:
fpgafs_prune_dir(dir);
return ret;
}
/* specific operations */
static int fpgafs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
if ((attr->ia_valid & ATTR_SIZE) &&
(attr->ia_size != inode->i_size))
return -EINVAL;
return inode_setattr(inode, attr);
}
static int fpgafs_new_file(struct super_block *sb, struct dentry *dentry,
const struct file_operations *fops, int mode,
struct fpga_context *ctx)
{
static struct inode_operations fpgafs_file_iops = {
.setattr = fpgafs_setattr,
};
struct inode *inode;
int ret;
ret = -ENOSPC;
inode = fpgafs_new_inode(sb, S_IFREG | mode);
if (!inode)
goto out;
ret = 0;
inode->i_op = &fpgafs_file_iops;
inode->i_fop = fops;
//inode->i_private = SPUFS_I(inode)->i_ctx = get_spu_context(ctx);
d_add(dentry, inode);
out:
return ret;
}
int fpgafs_mkdir( struct inode *dir, struct dentry *dentry, int mode)
{
int ret;
struct inode *inode;
struct fpga_context *ctx = NULL;
ret = -ENOSPC;
inode = fpgafs_new_inode(dir->i_sb, mode | S_IFDIR);
if (!inode)
return ret;
mutex_lock(&inode->i_mutex);
if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
inode->i_mode &= S_ISGID;
}
// ctx = alloc fpga context ....
// FPGAFS_I(inode)->i_ctx = ctx;
//if (!ctx)
// goto unmutex;
inode->i_op = &fpgafs_simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
ret = fpgafs_fill_dir(dentry, fpgafs_dir_contents, mode, ctx);
ret = 0;
//if (ret) {
// FREEE CONTENT
// goto unmutex;
//}
d_instantiate(dentry, inode);
dget(dentry);
dir->i_nlink++;
dentry->d_inode->i_nlink++;
//unmutex:
mutex_unlock(&inode->i_mutex);
return ret;
}
static void fpgafs_prune_dir(struct dentry *dir)
{
struct dentry *dentry, *tmp;
mutex_lock(&dir->d_inode->i_mutex);
list_for_each_entry_safe(dentry, tmp, &dir->d_subdirs, d_u.d_child) {
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!(d_unhashed(dentry)) && dentry->d_inode) {
dget_locked(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
simple_unlink(dir->d_inode, dentry);
spin_unlock(&dcache_lock);
dput(dentry);
} else {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
}
}
shrink_dcache_parent(dir);
mutex_unlock(&dir->d_inode->i_mutex);
}
/* Caller must hold parent->i_mutex */
static int fpgafs_rmdir(struct inode *dir, struct dentry *dentry)
{
/* remove all entries */
fpgafs_prune_dir(dentry);
//fpgafs_remove_inode
return simple_rmdir(dir, dentry);
}
/* SUPERBLOCK operations */
int fpgafs_fill_sb(struct super_block *sb, void *data, int silent)
{
struct inode *inode;
int ret = -ENOMEM;
static struct super_operations fpgafs_ops = {
//.read_inode = fpgafs_read_inode,
//.put_super = fpgafs_put_super,
.alloc_inode = fpgafs_alloc_inode,
.destroy_inode = fpgafs_destroy_inode,
.statfs = simple_statfs,
.delete_inode = fpgafs_delete_inode,
.drop_inode = generic_delete_inode,
};
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = FPGAFS_MAGIC;
sb->s_op = &fpgafs_ops;
inode = fpgafs_new_inode(sb, S_IFDIR | 0775);
if (!inode)
return ret;
inode->i_op = &fpgafs_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
FPGAFS_I(inode)->i_ctx = NULL;
sb->s_root = d_alloc_root(inode);
if (!sb->s_root)
return ret;
return 0;
}
static int fpgafs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
return get_sb_nodev(fs_type, flags, data, fpgafs_fill_sb, mnt);
}
static struct file_system_type fpgafs_type = {
.owner = THIS_MODULE,
.name = "fpgafs",
.get_sb = fpgafs_get_sb,
.kill_sb = kill_anon_super
};
static void fpgafs_init_once(void *p, struct kmem_cache * cachep,
unsigned long flags)
{
struct fpgafs_inode_info *fsi = p;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR) {
inode_init_once(&fsi->vfs_inode);
}
}
/* init exit functions ... */
int __init fpgafs_init(void)
{
fpgafs_inode_cache = kmem_cache_create("fpgafs_inode_cache",
sizeof(struct fpgafs_inode_info), 0,
SLAB_HWCACHE_ALIGN, fpgafs_init_once, NULL);
if(!fpgafs_inode_cache)
return -ENOMEM;
register_filesystem(&fpgafs_type);
return 0;
}
void __exit fpgafs_exit(void)
{
kmem_cache_destroy(fpgafs_inode_cache);
unregister_filesystem(&fpgafs_type);
}
module_init(fpgafs_init);
module_exit(fpgafs_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Benjamin Krill <ben@codiert.org>");