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-rw-r--r--fs/nfsd/nfsfh.h326
1 files changed, 326 insertions, 0 deletions
diff --git a/fs/nfsd/nfsfh.h b/fs/nfsd/nfsfh.h
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--- /dev/null
+++ b/fs/nfsd/nfsfh.h
@@ -0,0 +1,326 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
+ *
+ * This file describes the layout of the file handles as passed
+ * over the wire.
+ */
+#ifndef _LINUX_NFSD_NFSFH_H
+#define _LINUX_NFSD_NFSFH_H
+
+#include <linux/crc32.h>
+#include <linux/sunrpc/svc.h>
+#include <uapi/linux/nfsd/nfsfh.h>
+#include <linux/iversion.h>
+
+static inline __u32 ino_t_to_u32(ino_t ino)
+{
+ return (__u32) ino;
+}
+
+static inline ino_t u32_to_ino_t(__u32 uino)
+{
+ return (ino_t) uino;
+}
+
+/*
+ * This is the internal representation of an NFS handle used in knfsd.
+ * pre_mtime/post_version will be used to support wcc_attr's in NFSv3.
+ */
+typedef struct svc_fh {
+ struct knfsd_fh fh_handle; /* FH data */
+ int fh_maxsize; /* max size for fh_handle */
+ struct dentry * fh_dentry; /* validated dentry */
+ struct svc_export * fh_export; /* export pointer */
+
+ bool fh_locked; /* inode locked by us */
+ bool fh_want_write; /* remount protection taken */
+ int fh_flags; /* FH flags */
+#ifdef CONFIG_NFSD_V3
+ bool fh_post_saved; /* post-op attrs saved */
+ bool fh_pre_saved; /* pre-op attrs saved */
+
+ /* Pre-op attributes saved during fh_lock */
+ __u64 fh_pre_size; /* size before operation */
+ struct timespec64 fh_pre_mtime; /* mtime before oper */
+ struct timespec64 fh_pre_ctime; /* ctime before oper */
+ /*
+ * pre-op nfsv4 change attr: note must check IS_I_VERSION(inode)
+ * to find out if it is valid.
+ */
+ u64 fh_pre_change;
+
+ /* Post-op attributes saved in fh_unlock */
+ struct kstat fh_post_attr; /* full attrs after operation */
+ u64 fh_post_change; /* nfsv4 change; see above */
+#endif /* CONFIG_NFSD_V3 */
+
+} svc_fh;
+#define NFSD4_FH_FOREIGN (1<<0)
+#define SET_FH_FLAG(c, f) ((c)->fh_flags |= (f))
+#define HAS_FH_FLAG(c, f) ((c)->fh_flags & (f))
+
+enum nfsd_fsid {
+ FSID_DEV = 0,
+ FSID_NUM,
+ FSID_MAJOR_MINOR,
+ FSID_ENCODE_DEV,
+ FSID_UUID4_INUM,
+ FSID_UUID8,
+ FSID_UUID16,
+ FSID_UUID16_INUM,
+};
+
+enum fsid_source {
+ FSIDSOURCE_DEV,
+ FSIDSOURCE_FSID,
+ FSIDSOURCE_UUID,
+};
+extern enum fsid_source fsid_source(struct svc_fh *fhp);
+
+
+/*
+ * This might look a little large to "inline" but in all calls except
+ * one, 'vers' is constant so moste of the function disappears.
+ *
+ * In some cases the values are considered to be host endian and in
+ * others, net endian. fsidv is always considered to be u32 as the
+ * callers don't know which it will be. So we must use __force to keep
+ * sparse from complaining. Since these values are opaque to the
+ * client, that shouldn't be a problem.
+ */
+static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
+ u32 fsid, unsigned char *uuid)
+{
+ u32 *up;
+ switch(vers) {
+ case FSID_DEV:
+ fsidv[0] = (__force __u32)htonl((MAJOR(dev)<<16) |
+ MINOR(dev));
+ fsidv[1] = ino_t_to_u32(ino);
+ break;
+ case FSID_NUM:
+ fsidv[0] = fsid;
+ break;
+ case FSID_MAJOR_MINOR:
+ fsidv[0] = (__force __u32)htonl(MAJOR(dev));
+ fsidv[1] = (__force __u32)htonl(MINOR(dev));
+ fsidv[2] = ino_t_to_u32(ino);
+ break;
+
+ case FSID_ENCODE_DEV:
+ fsidv[0] = new_encode_dev(dev);
+ fsidv[1] = ino_t_to_u32(ino);
+ break;
+
+ case FSID_UUID4_INUM:
+ /* 4 byte fsid and inode number */
+ up = (u32*)uuid;
+ fsidv[0] = ino_t_to_u32(ino);
+ fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
+ break;
+
+ case FSID_UUID8:
+ /* 8 byte fsid */
+ up = (u32*)uuid;
+ fsidv[0] = up[0] ^ up[2];
+ fsidv[1] = up[1] ^ up[3];
+ break;
+
+ case FSID_UUID16:
+ /* 16 byte fsid - NFSv3+ only */
+ memcpy(fsidv, uuid, 16);
+ break;
+
+ case FSID_UUID16_INUM:
+ /* 8 byte inode and 16 byte fsid */
+ *(u64*)fsidv = (u64)ino;
+ memcpy(fsidv+2, uuid, 16);
+ break;
+ default: BUG();
+ }
+}
+
+static inline int key_len(int type)
+{
+ switch(type) {
+ case FSID_DEV: return 8;
+ case FSID_NUM: return 4;
+ case FSID_MAJOR_MINOR: return 12;
+ case FSID_ENCODE_DEV: return 8;
+ case FSID_UUID4_INUM: return 8;
+ case FSID_UUID8: return 8;
+ case FSID_UUID16: return 16;
+ case FSID_UUID16_INUM: return 24;
+ default: return 0;
+ }
+}
+
+/*
+ * Shorthand for dprintk()'s
+ */
+extern char * SVCFH_fmt(struct svc_fh *fhp);
+
+/*
+ * Function prototypes
+ */
+__be32 fh_verify(struct svc_rqst *, struct svc_fh *, umode_t, int);
+__be32 fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *);
+__be32 fh_update(struct svc_fh *);
+void fh_put(struct svc_fh *);
+
+static __inline__ struct svc_fh *
+fh_copy(struct svc_fh *dst, struct svc_fh *src)
+{
+ WARN_ON(src->fh_dentry || src->fh_locked);
+
+ *dst = *src;
+ return dst;
+}
+
+static inline void
+fh_copy_shallow(struct knfsd_fh *dst, struct knfsd_fh *src)
+{
+ dst->fh_size = src->fh_size;
+ memcpy(&dst->fh_base, &src->fh_base, src->fh_size);
+}
+
+static __inline__ struct svc_fh *
+fh_init(struct svc_fh *fhp, int maxsize)
+{
+ memset(fhp, 0, sizeof(*fhp));
+ fhp->fh_maxsize = maxsize;
+ return fhp;
+}
+
+static inline bool fh_match(struct knfsd_fh *fh1, struct knfsd_fh *fh2)
+{
+ if (fh1->fh_size != fh2->fh_size)
+ return false;
+ if (memcmp(fh1->fh_base.fh_pad, fh2->fh_base.fh_pad, fh1->fh_size) != 0)
+ return false;
+ return true;
+}
+
+static inline bool fh_fsid_match(struct knfsd_fh *fh1, struct knfsd_fh *fh2)
+{
+ if (fh1->fh_fsid_type != fh2->fh_fsid_type)
+ return false;
+ if (memcmp(fh1->fh_fsid, fh2->fh_fsid, key_len(fh1->fh_fsid_type)) != 0)
+ return false;
+ return true;
+}
+
+#ifdef CONFIG_CRC32
+/**
+ * knfsd_fh_hash - calculate the crc32 hash for the filehandle
+ * @fh - pointer to filehandle
+ *
+ * returns a crc32 hash for the filehandle that is compatible with
+ * the one displayed by "wireshark".
+ */
+
+static inline u32
+knfsd_fh_hash(struct knfsd_fh *fh)
+{
+ return ~crc32_le(0xFFFFFFFF, (unsigned char *)&fh->fh_base, fh->fh_size);
+}
+#else
+static inline u32
+knfsd_fh_hash(struct knfsd_fh *fh)
+{
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_NFSD_V3
+/*
+ * The wcc data stored in current_fh should be cleared
+ * between compound ops.
+ */
+static inline void
+fh_clear_wcc(struct svc_fh *fhp)
+{
+ fhp->fh_post_saved = false;
+ fhp->fh_pre_saved = false;
+}
+
+/*
+ * We could use i_version alone as the change attribute. However,
+ * i_version can go backwards after a reboot. On its own that doesn't
+ * necessarily cause a problem, but if i_version goes backwards and then
+ * is incremented again it could reuse a value that was previously used
+ * before boot, and a client who queried the two values might
+ * incorrectly assume nothing changed.
+ *
+ * By using both ctime and the i_version counter we guarantee that as
+ * long as time doesn't go backwards we never reuse an old value.
+ */
+static inline u64 nfsd4_change_attribute(struct kstat *stat,
+ struct inode *inode)
+{
+ u64 chattr;
+
+ chattr = stat->ctime.tv_sec;
+ chattr <<= 30;
+ chattr += stat->ctime.tv_nsec;
+ chattr += inode_query_iversion(inode);
+ return chattr;
+}
+
+extern void fill_pre_wcc(struct svc_fh *fhp);
+extern void fill_post_wcc(struct svc_fh *fhp);
+#else
+#define fh_clear_wcc(ignored)
+#define fill_pre_wcc(ignored)
+#define fill_post_wcc(notused)
+#endif /* CONFIG_NFSD_V3 */
+
+
+/*
+ * Lock a file handle/inode
+ * NOTE: both fh_lock and fh_unlock are done "by hand" in
+ * vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
+ * so, any changes here should be reflected there.
+ */
+
+static inline void
+fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
+{
+ struct dentry *dentry = fhp->fh_dentry;
+ struct inode *inode;
+
+ BUG_ON(!dentry);
+
+ if (fhp->fh_locked) {
+ printk(KERN_WARNING "fh_lock: %pd2 already locked!\n",
+ dentry);
+ return;
+ }
+
+ inode = d_inode(dentry);
+ inode_lock_nested(inode, subclass);
+ fill_pre_wcc(fhp);
+ fhp->fh_locked = true;
+}
+
+static inline void
+fh_lock(struct svc_fh *fhp)
+{
+ fh_lock_nested(fhp, I_MUTEX_NORMAL);
+}
+
+/*
+ * Unlock a file handle/inode
+ */
+static inline void
+fh_unlock(struct svc_fh *fhp)
+{
+ if (fhp->fh_locked) {
+ fill_post_wcc(fhp);
+ inode_unlock(d_inode(fhp->fh_dentry));
+ fhp->fh_locked = false;
+ }
+}
+
+#endif /* _LINUX_NFSD_NFSFH_H */