/* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU General Public License version 2. */ #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/buffer_head.h> #include <linux/exportfs.h> #include <linux/gfs2_ondisk.h> #include <linux/crc32.h> #include "gfs2.h" #include "incore.h" #include "dir.h" #include "glock.h" #include "glops.h" #include "inode.h" #include "super.h" #include "rgrp.h" #include "util.h" #define GFS2_SMALL_FH_SIZE 4 #define GFS2_LARGE_FH_SIZE 8 #define GFS2_OLD_FH_SIZE 10 static int gfs2_encode_fh(struct inode *inode, __u32 *p, int *len, struct inode *parent) { __be32 *fh = (__force __be32 *)p; struct super_block *sb = inode->i_sb; struct gfs2_inode *ip = GFS2_I(inode); if (parent && (*len < GFS2_LARGE_FH_SIZE)) { *len = GFS2_LARGE_FH_SIZE; return 255; } else if (*len < GFS2_SMALL_FH_SIZE) { *len = GFS2_SMALL_FH_SIZE; return 255; } fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32); fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF); fh[2] = cpu_to_be32(ip->i_no_addr >> 32); fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF); *len = GFS2_SMALL_FH_SIZE; if (!parent || inode == sb->s_root->d_inode) return *len; ip = GFS2_I(parent); fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32); fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF); fh[6] = cpu_to_be32(ip->i_no_addr >> 32); fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF); *len = GFS2_LARGE_FH_SIZE; return *len; } struct get_name_filldir { struct gfs2_inum_host inum; char *name; }; static int get_name_filldir(void *opaque, const char *name, int length, loff_t offset, u64 inum, unsigned int type) { struct get_name_filldir *gnfd = opaque; if (inum != gnfd->inum.no_addr) return 0; memcpy(gnfd->name, name, length); gnfd->name[length] = 0; return 1; } static int gfs2_get_name(struct dentry *parent, char *name, struct dentry *child) { struct inode *dir = parent->d_inode; struct inode *inode = child->d_inode; struct gfs2_inode *dip, *ip; struct get_name_filldir gnfd; struct gfs2_holder gh; u64 offset = 0; int error; struct file_ra_state f_ra = { .start = 0 }; if (!dir) return -EINVAL; if (!S_ISDIR(dir->i_mode) || !inode) return -EINVAL; dip = GFS2_I(dir); ip = GFS2_I(inode); *name = 0; gnfd.inum.no_addr = ip->i_no_addr; gnfd.inum.no_formal_ino = ip->i_no_formal_ino; gnfd.name = name; error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh); if (error) return error; error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir, &f_ra); gfs2_glock_dq_uninit(&gh); if (!error && !*name) error = -ENOENT; return error; } static struct dentry *gfs2_get_parent(struct dentry *child) { return d_obtain_alias(gfs2_lookupi(child->d_inode, &gfs2_qdotdot, 1)); } static struct dentry *gfs2_get_dentry(struct super_block *sb, struct gfs2_inum_host *inum) { struct gfs2_sbd *sdp = sb->s_fs_info; struct inode *inode; inode = gfs2_ilookup(sb, inum->no_addr, 0); if (inode) { if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) { iput(inode); return ERR_PTR(-ESTALE); } goto out_inode; } inode = gfs2_lookup_by_inum(sdp, inum->no_addr, &inum->no_formal_ino, GFS2_BLKST_DINODE); if (IS_ERR(inode)) return ERR_CAST(inode); out_inode: return d_obtain_alias(inode); } static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { struct gfs2_inum_host this; __be32 *fh = (__force __be32 *)fid->raw; switch (fh_type) { case GFS2_SMALL_FH_SIZE: case GFS2_LARGE_FH_SIZE: case GFS2_OLD_FH_SIZE: this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32; this.no_formal_ino |= be32_to_cpu(fh[1]); this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32; this.no_addr |= be32_to_cpu(fh[3]); return gfs2_get_dentry(sb, &this); default: return NULL; } } static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { struct gfs2_inum_host parent; __be32 *fh = (__force __be32 *)fid->raw; switch (fh_type) { case GFS2_LARGE_FH_SIZE: case GFS2_OLD_FH_SIZE: parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32; parent.no_formal_ino |= be32_to_cpu(fh[5]); parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32; parent.no_addr |= be32_to_cpu(fh[7]); return gfs2_get_dentry(sb, &parent); default: return NULL; } } const struct export_operations gfs2_export_ops = { .encode_fh = gfs2_encode_fh, .fh_to_dentry = gfs2_fh_to_dentry, .fh_to_parent = gfs2_fh_to_parent, .get_name = gfs2_get_name, .get_parent = gfs2_get_parent, };