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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * Copyright (c) 2024 Paulo Alcantara <pc@manguebit.com>4 */5 6#ifndef _CIFS_REPARSE_H7#define _CIFS_REPARSE_H8 9#include <linux/fs.h>10#include <linux/stat.h>11#include <linux/uidgid.h>12#include "fs_context.h"13#include "cifsglob.h"14 15/*16 * Used only by cifs.ko to ignore reparse points from files when client or17 * server doesn't support FSCTL_GET_REPARSE_POINT.18 */19#define IO_REPARSE_TAG_INTERNAL ((__u32)~0U)20 21static inline dev_t reparse_mkdev(void *ptr)22{23 u64 v = le64_to_cpu(*(__le64 *)ptr);24 25 return MKDEV(v & 0xffffffff, v >> 32);26}27 28static inline kuid_t wsl_make_kuid(struct cifs_sb_info *cifs_sb,29 void *ptr)30{31 u32 uid = le32_to_cpu(*(__le32 *)ptr);32 33 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)34 return cifs_sb->ctx->linux_uid;35 return make_kuid(current_user_ns(), uid);36}37 38static inline kgid_t wsl_make_kgid(struct cifs_sb_info *cifs_sb,39 void *ptr)40{41 u32 gid = le32_to_cpu(*(__le32 *)ptr);42 43 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)44 return cifs_sb->ctx->linux_gid;45 return make_kgid(current_user_ns(), gid);46}47 48static inline u64 reparse_mode_nfs_type(mode_t mode)49{50 switch (mode & S_IFMT) {51 case S_IFBLK: return NFS_SPECFILE_BLK;52 case S_IFCHR: return NFS_SPECFILE_CHR;53 case S_IFIFO: return NFS_SPECFILE_FIFO;54 case S_IFSOCK: return NFS_SPECFILE_SOCK;55 }56 return 0;57}58 59static inline u32 reparse_mode_wsl_tag(mode_t mode)60{61 switch (mode & S_IFMT) {62 case S_IFBLK: return IO_REPARSE_TAG_LX_BLK;63 case S_IFCHR: return IO_REPARSE_TAG_LX_CHR;64 case S_IFIFO: return IO_REPARSE_TAG_LX_FIFO;65 case S_IFSOCK: return IO_REPARSE_TAG_AF_UNIX;66 }67 return 0;68}69 70/*71 * Match a reparse point inode if reparse tag and ctime haven't changed.72 *73 * Windows Server updates ctime of reparse points when their data have changed.74 * The server doesn't allow changing reparse tags from existing reparse points,75 * though it's worth checking.76 */77static inline bool reparse_inode_match(struct inode *inode,78 struct cifs_fattr *fattr)79{80 struct cifsInodeInfo *cinode = CIFS_I(inode);81 struct timespec64 ctime = inode_get_ctime(inode);82 83 /*84 * Do not match reparse tags when client or server doesn't support85 * FSCTL_GET_REPARSE_POINT. @fattr->cf_cifstag should contain correct86 * reparse tag from query dir response but the client won't be able to87 * read the reparse point data anyway. This spares us a revalidation.88 */89 if (cinode->reparse_tag != IO_REPARSE_TAG_INTERNAL &&90 cinode->reparse_tag != fattr->cf_cifstag)91 return false;92 return (cinode->cifsAttrs & ATTR_REPARSE) &&93 timespec64_equal(&ctime, &fattr->cf_ctime);94}95 96static inline bool cifs_open_data_reparse(struct cifs_open_info_data *data)97{98 struct smb2_file_all_info *fi = &data->fi;99 u32 attrs = le32_to_cpu(fi->Attributes);100 bool ret;101 102 ret = data->reparse_point || (attrs & ATTR_REPARSE);103 if (ret)104 attrs |= ATTR_REPARSE;105 fi->Attributes = cpu_to_le32(attrs);106 return ret;107}108 109bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,110 struct cifs_fattr *fattr,111 struct cifs_open_info_data *data);112int smb2_create_reparse_symlink(const unsigned int xid, struct inode *inode,113 struct dentry *dentry, struct cifs_tcon *tcon,114 const char *full_path, const char *symname);115int smb2_mknod_reparse(unsigned int xid, struct inode *inode,116 struct dentry *dentry, struct cifs_tcon *tcon,117 const char *full_path, umode_t mode, dev_t dev);118int smb2_parse_reparse_point(struct cifs_sb_info *cifs_sb, struct kvec *rsp_iov,119 struct cifs_open_info_data *data);120 121#endif /* _CIFS_REPARSE_H */122