On Fri, 2016-12-02 at 14:40 -0800, Roper, Matthew D wrote: > On Thu, Dec 01, 2016 at 01:44:15PM +0530, swati.dhingra@xxxxxxxxx wrote: > > From: Swati Dhingra <swati.dhingra@xxxxxxxxx> > > > > The patch introduces a new pseudo filesystem type, named 'drmfs' which is > > intended to house the files for the data generated by drm subsystem that > > cannot be accommodated by any of the existing filesystems. > > The filesystem is modelled on the lines of existing pseudo-filesystems such > > as debugfs/tracefs, and borrows ideas from their implementation. > > This filesystem will be appearing at sys/kernel/drm. > > > > A new config 'CONFIG_DRMFS' is introduced to enable/disable the filesystem, > > which is dependent on CONFIG_DRM. > > The filesystem will not be registered standalone during kernel init time, > > instead it is intended to be initialized/registered during drm initialization. > > > > The intent for introduction of the filesystem is to act as a location to hold > > various kinds of data output from Linux DRM subsystems, which can't really fit > > anywhere else into the existing filesystems such as debugfs/sysfs etc. All these > > filesystems have their own constraints and are intended to output a particular > > type of data such as attributes and small debug parameter data. Due to these > > constraints, there is a need for a new pseudo filesytem, customizable to DRM > > specific requirements and catering to the needs to DRM subsystem components > > Am I correct in assuming the data made available via drmfs is not > considered ABI? If we're not going to guarantee a stable ABI and > backward compatibility forever for the items exposed here, then it's > important to state that very explicitly up front so that no userspace > software gets written with the wrong assumption. I'd suggest making an > explicit note one way or the other in the commit message here and > probably in the Kconfig help text as well. > > > Matt > We've intended for drmfs to be ABI as Chris mentioned here: https://lists.freedesktop.org/archives/intel-gfx/2016-December/113245.html The intent is for drmfs to be a stable ABI for the files it's holding. This can be ensured moresoever since it'll be under sole control of drm. Chris, can you correct me if i'm wrong. -sourab > > > > Signed-off-by: Sourab Gupta <sourab.gupta@xxxxxxxxx> > > Signed-off-by: Swati Dhingra <swati.dhingra@xxxxxxxxx> > > --- > > drivers/gpu/drm/drm_drv.c | 1 + > > fs/Kconfig | 9 + > > fs/Makefile | 1 + > > fs/drmfs/Makefile | 3 + > > fs/drmfs/inode.c | 561 +++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/drmfs.h | 56 +++++ > > include/uapi/linux/magic.h | 3 + > > 7 files changed, 634 insertions(+) > > create mode 100644 fs/drmfs/Makefile > > create mode 100644 fs/drmfs/inode.c > > create mode 100644 include/linux/drmfs.h > > > > diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c > > index 6dbb986..84fcfcb 100644 > > --- a/drivers/gpu/drm/drm_drv.c > > +++ b/drivers/gpu/drm/drm_drv.c > > @@ -27,6 +27,7 @@ > > */ > > > > #include <linux/debugfs.h> > > +#include <linux/drmfs.h> > > #include <linux/fs.h> > > #include <linux/module.h> > > #include <linux/moduleparam.h> > > diff --git a/fs/Kconfig b/fs/Kconfig > > index 4bd03a2..7d0ac20 100644 > > --- a/fs/Kconfig > > +++ b/fs/Kconfig > > @@ -200,6 +200,15 @@ config HUGETLBFS > > config HUGETLB_PAGE > > def_bool HUGETLBFS > > > > +config DRMFS > > + bool "Drmfs file system support" > > + depends on DRM > > + help > > + Drmfs is a pseudo file system for drm subsystem output data. > > + > > + drmfs is a filesystem to hold miscellaneous output data from drm > > + subsystems. > > + > > config ARCH_HAS_GIGANTIC_PAGE > > bool > > > > diff --git a/fs/Makefile b/fs/Makefile > > index ed2b632..b34a96e 100644 > > --- a/fs/Makefile > > +++ b/fs/Makefile > > @@ -120,6 +120,7 @@ obj-$(CONFIG_BEFS_FS) += befs/ > > obj-$(CONFIG_HOSTFS) += hostfs/ > > obj-$(CONFIG_CACHEFILES) += cachefiles/ > > obj-$(CONFIG_DEBUG_FS) += debugfs/ > > +obj-$(CONFIG_DRMFS) += drmfs/ > > obj-$(CONFIG_TRACING) += tracefs/ > > obj-$(CONFIG_OCFS2_FS) += ocfs2/ > > obj-$(CONFIG_BTRFS_FS) += btrfs/ > > diff --git a/fs/drmfs/Makefile b/fs/drmfs/Makefile > > new file mode 100644 > > index 0000000..ac87e497 > > --- /dev/null > > +++ b/fs/drmfs/Makefile > > @@ -0,0 +1,3 @@ > > +drmfs-objs := inode.o > > + > > +obj-$(CONFIG_DRMFS) += drmfs.o > > diff --git a/fs/drmfs/inode.c b/fs/drmfs/inode.c > > new file mode 100644 > > index 0000000..9220705 > > --- /dev/null > > +++ b/fs/drmfs/inode.c > > @@ -0,0 +1,561 @@ > > +/* > > + * Copyright © 2014 Intel Corporation > > + * > > + * Permission is hereby granted, free of charge, to any person obtaining a > > + * copy of this software and associated documentation files (the "Software"), > > + * to deal in the Software without restriction, including without limitation > > + * the rights to use, copy, modify, merge, publish, distribute, sublicense, > > + * and/or sell copies of the Software, and to permit persons to whom the > > + * Software is furnished to do so, subject to the following conditions: > > + * > > + * The above copyright notice and this permission notice (including the next > > + * paragraph) shall be included in all copies or substantial portions of the > > + * Software. > > + * > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL > > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER > > + * DEALINGS IN THE SOFTWARE. > > + * > > + * Authors: > > + * Swati Dhingra <swati.dhingra@xxxxxxxxx> > > + * Sourab Gupta <sourab.gupta@xxxxxxxxx> > > + * Akash Goel <akash.goel@xxxxxxxxx> > > + */ > > + > > +/* > > + * drmfs is the filesystem used for output of drm subsystem data > > + */ > > + > > +#include <linux/module.h> > > +#include <linux/fs.h> > > +#include <linux/mount.h> > > +#include <linux/kobject.h> > > +#include <linux/namei.h> > > +#include <linux/drmfs.h> > > +#include <linux/fsnotify.h> > > +#include <linux/seq_file.h> > > +#include <linux/parser.h> > > +#include <linux/magic.h> > > +#include <linux/slab.h> > > + > > +#define DRMFS_DEFAULT_MODE 0700 > > + > > +static struct vfsmount *drmfs_mount; > > +static int drmfs_mount_count; > > +static bool drmfs_registered; > > + > > +static ssize_t default_read_file(struct file *file, char __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + return 0; > > +} > > + > > +static ssize_t default_write_file(struct file *file, const char __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + return count; > > +} > > + > > +static const struct file_operations drmfs_default_file_operations = { > > + .read = default_read_file, > > + .write = default_write_file, > > + .open = simple_open, > > + .llseek = noop_llseek, > > +}; > > + > > +static struct inode *drmfs_get_inode(struct super_block *sb) > > +{ > > + struct inode *inode = new_inode(sb); > > + > > + if (inode) { > > + inode->i_ino = get_next_ino(); > > + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; > > + } > > + return inode; > > +} > > + > > +struct drmfs_mount_opts { > > + kuid_t uid; > > + kgid_t gid; > > + umode_t mode; > > +}; > > + > > +enum { > > + Opt_uid, > > + Opt_gid, > > + Opt_mode, > > + Opt_err > > +}; > > + > > +static const match_table_t tokens = { > > + {Opt_uid, "uid=%u"}, > > + {Opt_gid, "gid=%u"}, > > + {Opt_mode, "mode=%o"}, > > + {Opt_err, NULL} > > +}; > > + > > +struct drmfs_fs_info { > > + struct drmfs_mount_opts mount_opts; > > +}; > > + > > +static int drmfs_parse_options(char *data, struct drmfs_mount_opts *opts) > > +{ > > + substring_t args[MAX_OPT_ARGS]; > > + int option; > > + int token; > > + kuid_t uid; > > + kgid_t gid; > > + char *p; > > + > > + opts->mode = DRMFS_DEFAULT_MODE; > > + > > + while ((p = strsep(&data, ",")) != NULL) { > > + if (!*p) > > + continue; > > + > > + token = match_token(p, tokens, args); > > + switch (token) { > > + case Opt_uid: > > + if (match_int(&args[0], &option)) > > + return -EINVAL; > > + uid = make_kuid(current_user_ns(), option); > > + if (!uid_valid(uid)) > > + return -EINVAL; > > + opts->uid = uid; > > + break; > > + case Opt_gid: > > + if (match_int(&args[0], &option)) > > + return -EINVAL; > > + gid = make_kgid(current_user_ns(), option); > > + if (!gid_valid(gid)) > > + return -EINVAL; > > + opts->gid = gid; > > + break; > > + case Opt_mode: > > + if (match_octal(&args[0], &option)) > > + return -EINVAL; > > + opts->mode = option & S_IALLUGO; > > + break; > > + /* > > + * We might like to report bad mount options here > > + */ > > + } > > + } > > + > > + return 0; > > +} > > + > > +static int drmfs_apply_options(struct super_block *sb) > > +{ > > + struct drmfs_fs_info *fsi = sb->s_fs_info; > > + struct inode *inode = sb->s_root->d_inode; > > + struct drmfs_mount_opts *opts = &fsi->mount_opts; > > + > > + inode->i_mode &= ~S_IALLUGO; > > + inode->i_mode |= opts->mode; > > + > > + inode->i_uid = opts->uid; > > + inode->i_gid = opts->gid; > > + > > + return 0; > > +} > > + > > +static int drmfs_remount(struct super_block *sb, int *flags, char *data) > > +{ > > + int err; > > + struct drmfs_fs_info *fsi = sb->s_fs_info; > > + > > + sync_filesystem(sb); > > + err = drmfs_parse_options(data, &fsi->mount_opts); > > + if (err) > > + goto fail; > > + > > + drmfs_apply_options(sb); > > + > > +fail: > > + return err; > > +} > > + > > +static int drmfs_show_options(struct seq_file *m, struct dentry *root) > > +{ > > + struct drmfs_fs_info *fsi = root->d_sb->s_fs_info; > > + struct drmfs_mount_opts *opts = &fsi->mount_opts; > > + > > + if (!uid_eq(opts->uid, GLOBAL_ROOT_UID)) > > + seq_printf(m, ",uid=%u", > > + from_kuid_munged(&init_user_ns, opts->uid)); > > + if (!gid_eq(opts->gid, GLOBAL_ROOT_GID)) > > + seq_printf(m, ",gid=%u", > > + from_kgid_munged(&init_user_ns, opts->gid)); > > + if (opts->mode != DRMFS_DEFAULT_MODE) > > + seq_printf(m, ",mode=%o", opts->mode); > > + > > + return 0; > > +} > > + > > +static const struct super_operations drmfs_super_operations = { > > + .statfs = simple_statfs, > > + .remount_fs = drmfs_remount, > > + .show_options = drmfs_show_options, > > +}; > > + > > +static int drm_fill_super(struct super_block *sb, void *data, int silent) > > +{ > > + static struct tree_descr drm_files[] = { {""} }; > > + struct drmfs_fs_info *fsi; > > + int err; > > + > > + save_mount_options(sb, data); > > + > > + fsi = kzalloc(sizeof(struct drmfs_fs_info), GFP_KERNEL); > > + sb->s_fs_info = fsi; > > + if (!fsi) { > > + err = -ENOMEM; > > + goto fail; > > + } > > + > > + err = drmfs_parse_options(data, &fsi->mount_opts); > > + if (err) > > + goto fail; > > + > > + err = simple_fill_super(sb, DRMFS_MAGIC, drm_files); > > + if (err) > > + goto fail; > > + > > + sb->s_op = &drmfs_super_operations; > > + > > + drmfs_apply_options(sb); > > + > > + return 0; > > + > > +fail: > > + kfree(fsi); > > + sb->s_fs_info = NULL; > > + return err; > > +} > > + > > +static struct dentry *drm_mount(struct file_system_type *fs_type, > > + int flags, const char *dev_name, > > + void *data) > > +{ > > + return mount_single(fs_type, flags, data, drm_fill_super); > > +} > > + > > +static struct file_system_type drm_fs_type = { > > + .owner = THIS_MODULE, > > + .name = "drmfs", > > + .mount = drm_mount, > > + .kill_sb = kill_litter_super, > > +}; > > +MODULE_ALIAS_FS("drmfs"); > > + > > +static struct dentry *start_creating(const char *name, struct dentry *parent) > > +{ > > + struct dentry *dentry; > > + int error; > > + > > + pr_debug("drmfs: creating file '%s'\n", name); > > + > > + error = simple_pin_fs(&drm_fs_type, &drmfs_mount, > > + &drmfs_mount_count); > > + if (error) > > + return ERR_PTR(error); > > + > > + /* If the parent is not specified, we create it in the root. > > + * We need the root dentry to do this, which is in the super > > + * block. A pointer to that is in the struct vfsmount that we > > + * have around. > > + */ > > + if (!parent) > > + parent = drmfs_mount->mnt_root; > > + > > + inode_lock(parent->d_inode); > > + dentry = lookup_one_len(name, parent, strlen(name)); > > + if (!IS_ERR(dentry) && dentry->d_inode) { > > + dput(dentry); > > + dentry = ERR_PTR(-EEXIST); > > + } > > + > > + if (IS_ERR(dentry)) { > > + inode_unlock(parent->d_inode); > > + simple_release_fs(&drmfs_mount, &drmfs_mount_count); > > + } > > + > > + return dentry; > > +} > > + > > +static struct dentry *failed_creating(struct dentry *dentry) > > +{ > > + inode_unlock(dentry->d_parent->d_inode); > > + dput(dentry); > > + simple_release_fs(&drmfs_mount, &drmfs_mount_count); > > + return NULL; > > +} > > + > > +static struct dentry *end_creating(struct dentry *dentry) > > +{ > > + inode_unlock(dentry->d_parent->d_inode); > > + return dentry; > > +} > > + > > +/** > > + * drmfs_create_file - create a file in the drmfs filesystem > > + * @name: a pointer to a string containing the name of the file to create. > > + * @mode: the permission that the file should have. > > + * @parent: a pointer to the parent dentry for this file. This should be a > > + * directory dentry if set. If this parameter is NULL, then the > > + * file will be created in the root of the drmfs filesystem. > > + * @data: a pointer to something that the caller will want to get to later > > + * on. The inode.i_private pointer will point to this value on > > + * the open() call. > > + * @fops: a pointer to a struct file_operations that should be used for > > + * this file. > > + * > > + * This is the basic "create a file" function for drmfs. It allows for a > > + * wide range of flexibility in creating a file, or a directory (if you want > > + * to create a directory, the drmfs_create_dir() function is > > + * recommended to be used instead.) > > + * > > + * This function will return a pointer to a dentry if it succeeds. This > > + * pointer must be passed to the drmfs_remove() function when the file is > > + * to be removed (no automatic cleanup happens if your module is unloaded, > > + * you are responsible here.) If an error occurs, %NULL will be returned. > > + * > > + */ > > +struct dentry *drmfs_create_file(const char *name, umode_t mode, > > + struct dentry *parent, void *data, > > + const struct file_operations *fops) > > +{ > > + struct dentry *dentry; > > + struct inode *inode; > > + > > + if (!(mode & S_IFMT)) > > + mode |= S_IFREG; > > + > > + if (WARN_ON(!S_ISREG(mode))) > > + return NULL; > > + > > + dentry = start_creating(name, parent); > > + > > + if (IS_ERR(dentry)) > > + return NULL; > > + > > + inode = drmfs_get_inode(dentry->d_sb); > > + if (unlikely(!inode)) > > + return failed_creating(dentry); > > + > > + inode->i_mode = mode; > > + inode->i_fop = fops ? fops : &drmfs_default_file_operations; > > + inode->i_private = data; > > + d_instantiate(dentry, inode); > > + fsnotify_create(dentry->d_parent->d_inode, dentry); > > + return end_creating(dentry); > > +} > > +EXPORT_SYMBOL(drmfs_create_file); > > + > > +static struct dentry *__create_dir(const char *name, struct dentry *parent, > > + const struct inode_operations *ops) > > +{ > > + struct dentry *dentry = start_creating(name, parent); > > + struct inode *inode; > > + > > + if (IS_ERR(dentry)) > > + return NULL; > > + > > + inode = drmfs_get_inode(dentry->d_sb); > > + if (unlikely(!inode)) > > + return failed_creating(dentry); > > + > > + inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; > > + inode->i_op = ops; > > + inode->i_fop = &simple_dir_operations; > > + > > + /* directory inodes start off with i_nlink == 2 (for "." entry) */ > > + inc_nlink(inode); > > + d_instantiate(dentry, inode); > > + inc_nlink(dentry->d_parent->d_inode); > > + fsnotify_mkdir(dentry->d_parent->d_inode, dentry); > > + return end_creating(dentry); > > +} > > + > > +/** > > + * drmfs_create_dir - create a directory in the drmfs filesystem > > + * @name: a pointer to a string containing the name of the directory to > > + * create. > > + * @parent: a pointer to the parent dentry for this file. This should be a > > + * directory dentry if set. If this parameter is NULL, then the > > + * directory will be created in the root of the drmfs filesystem. > > + * > > + * This function creates a directory in drmfs with the given name. > > + * > > + * This function will return a pointer to a dentry if it succeeds. This > > + * pointer must be passed to the drmfs_remove() function when the file is > > + * to be removed. If an error occurs, %NULL will be returned. > > + * > > + */ > > +struct dentry *drmfs_create_dir(const char *name, struct dentry *parent) > > +{ > > + return __create_dir(name, parent, &simple_dir_inode_operations); > > +} > > +EXPORT_SYMBOL(drmfs_create_dir); > > + > > +static int __drmfs_remove(struct dentry *dentry, struct dentry *parent) > > +{ > > + int ret = 0; > > + > > + if (simple_positive(dentry)) { > > + if (dentry->d_inode) { > > + dget(dentry); > > + switch (dentry->d_inode->i_mode & S_IFMT) { > > + case S_IFDIR: > > + ret = simple_rmdir(parent->d_inode, dentry); > > + break; > > + default: > > + simple_unlink(parent->d_inode, dentry); > > + break; > > + } > > + if (!ret) > > + d_delete(dentry); > > + dput(dentry); > > + } > > + } > > + return ret; > > +} > > + > > + > > +/** > > + * drmfs_remove - removes a file or directory from the drmfs filesystem > > + * @dentry: a pointer to a the dentry of the file or directory to be > > + * removed. > > + * > > + * This function removes a file or directory in drmfs that was previously > > + * created with a call to another drmfs function (like > > + * drmfs_create_file() or variants thereof.) > > + */ > > +void drmfs_remove(struct dentry *dentry) > > +{ > > + struct dentry *parent; > > + int ret; > > + > > + if (IS_ERR_OR_NULL(dentry)) > > + return; > > + > > + parent = dentry->d_parent; > > + inode_lock(parent->d_inode); > > + ret = __drmfs_remove(dentry, parent); > > + inode_unlock(parent->d_inode); > > + if (!ret) > > + simple_release_fs(&drmfs_mount, &drmfs_mount_count); > > +} > > +EXPORT_SYMBOL(drmfs_remove); > > + > > +/** > > + * drmfs_remove_recursive - recursively removes a directory > > + * @dentry: a pointer to a the dentry of the directory to be removed. > > + * > > + * This function recursively removes a directory tree in drmfs that > > + * was previously created with a call to another drmfs function > > + * (like drmfs_create_file() or variants thereof.) > > + */ > > +void drmfs_remove_recursive(struct dentry *dentry) > > +{ > > + struct dentry *child, *parent; > > + > > + if (IS_ERR_OR_NULL(dentry)) > > + return; > > + > > + parent = dentry; > > + down: > > + inode_lock(parent->d_inode); > > + loop: > > + /* > > + * The parent->d_subdirs is protected by the d_lock. Outside that > > + * lock, the child can be unlinked and set to be freed which can > > + * use the d_u.d_child as the rcu head and corrupt this list. > > + */ > > + spin_lock(&parent->d_lock); > > + list_for_each_entry(child, &parent->d_subdirs, d_child) { > > + if (!simple_positive(child)) > > + continue; > > + > > + /* perhaps simple_empty(child) makes more sense */ > > + if (!list_empty(&child->d_subdirs)) { > > + spin_unlock(&parent->d_lock); > > + inode_unlock(parent->d_inode); > > + parent = child; > > + goto down; > > + } > > + > > + spin_unlock(&parent->d_lock); > > + > > + if (!__drmfs_remove(child, parent)) > > + simple_release_fs(&drmfs_mount, &drmfs_mount_count); > > + > > + /* > > + * The parent->d_lock protects against child from unlinking > > + * from d_subdirs. When releasing the parent->d_lock we can > > + * no longer trust that the next pointer is valid. > > + * Restart the loop. We'll skip this one with the > > + * simple_positive() check. > > + */ > > + goto loop; > > + } > > + spin_unlock(&parent->d_lock); > > + > > + inode_unlock(parent->d_inode); > > + child = parent; > > + parent = parent->d_parent; > > + inode_lock(parent->d_inode); > > + > > + if (child != dentry) > > + /* go up */ > > + goto loop; > > + > > + if (!__drmfs_remove(child, parent)) > > + simple_release_fs(&drmfs_mount, &drmfs_mount_count); > > + inode_unlock(parent->d_inode); > > +} > > +EXPORT_SYMBOL(drmfs_remove_recursive); > > + > > +/** > > + * drmfs_initialized - Tells whether drmfs has been registered > > + */ > > +bool drmfs_initialized(void) > > +{ > > + return drmfs_registered; > > +} > > +EXPORT_SYMBOL(drmfs_initialized); > > + > > +int drmfs_init(void) > > +{ > > + int retval; > > + > > + retval = sysfs_create_mount_point(kernel_kobj, "drm"); > > + if (retval) > > + return -EINVAL; > > + > > + retval = register_filesystem(&drm_fs_type); > > + if (!retval) > > + drmfs_registered = true; > > + > > + return retval; > > +} > > +EXPORT_SYMBOL(drmfs_init); > > + > > +int drmfs_fini(void) > > +{ > > + int retval; > > + > > + retval = unregister_filesystem(&drm_fs_type); > > + if (retval) > > + return retval; > > + > > + drmfs_registered = false; > > + > > + sysfs_remove_mount_point(kernel_kobj, "drm"); > > +} > > +EXPORT_SYMBOL(drmfs_fini); > > diff --git a/include/linux/drmfs.h b/include/linux/drmfs.h > > new file mode 100644 > > index 0000000..3091480 > > --- /dev/null > > +++ b/include/linux/drmfs.h > > @@ -0,0 +1,56 @@ > > +/* > > + * Copyright © 2014 Intel Corporation > > + * > > + * Permission is hereby granted, free of charge, to any person obtaining a > > + * copy of this software and associated documentation files (the "Software"), > > + * to deal in the Software without restriction, including without limitation > > + * the rights to use, copy, modify, merge, publish, distribute, sublicense, > > + * and/or sell copies of the Software, and to permit persons to whom the > > + * Software is furnished to do so, subject to the following conditions: > > + * > > + * The above copyright notice and this permission notice (including the next > > + * paragraph) shall be included in all copies or substantial portions of the > > + * Software. > > + * > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL > > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER > > + * DEALINGS IN THE SOFTWARE. > > + * > > + * Authors: > > + * Swati Dhingra <swati.dhingra@xxxxxxxxx> > > + * Sourab Gupta <sourab.gupta@xxxxxxxxx> > > + * Akash Goel <akash.goel@xxxxxxxxx> > > + */ > > + > > +#ifndef _DRMFS_H_ > > +#define _DRMFS_H_ > > + > > +#include <linux/fs.h> > > +#include <linux/seq_file.h> > > + > > +#include <linux/types.h> > > + > > +struct file_operations; > > + > > +#ifdef CONFIG_DRMFS > > + > > +struct dentry *drmfs_create_file(const char *name, umode_t mode, > > + struct dentry *parent, void *data, > > + const struct file_operations *fops); > > + > > +struct dentry *drmfs_create_dir(const char *name, struct dentry *parent); > > + > > +void drmfs_remove(struct dentry *dentry); > > +void drmfs_remove_recursive(struct dentry *dentry); > > + > > +bool drmfs_initialized(void); > > +int drmfs_init(void); > > +int drmfs_fini(void); > > + > > +#endif /* CONFIG_DRMFS */ > > + > > +#endif > > diff --git a/include/uapi/linux/magic.h b/include/uapi/linux/magic.h > > index 9bd5594..ef01eb7 100644 > > --- a/include/uapi/linux/magic.h > > +++ b/include/uapi/linux/magic.h > > @@ -61,6 +61,9 @@ > > #define STACK_END_MAGIC 0x57AC6E9D > > > > #define TRACEFS_MAGIC 0x74726163 > > +#define DRMFS_MAGIC 0x84724143 /* some random number. > > + * Is there a better way? > > + */ > > > > #define V9FS_MAGIC 0x01021997 > > > > -- > > 2.7.4 > > > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
