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1// SPDX-License-Identifier: GPL-2.02/* cnode related routines for the coda kernel code3 (C) 1996 Peter Braam4 */5 6#include <linux/types.h>7#include <linux/string.h>8#include <linux/time.h>9 10#include <linux/coda.h>11#include <linux/pagemap.h>12#include "coda_psdev.h"13#include "coda_linux.h"14 15static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2)16{17 return memcmp(fid1, fid2, sizeof(*fid1)) == 0;18}19 20static const struct inode_operations coda_symlink_inode_operations = {21 .get_link = page_get_link,22 .setattr = coda_setattr,23};24 25/* cnode.c */26static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr)27{28 coda_vattr_to_iattr(inode, attr);29 30 if (S_ISREG(inode->i_mode)) {31 inode->i_op = &coda_file_inode_operations;32 inode->i_fop = &coda_file_operations;33 } else if (S_ISDIR(inode->i_mode)) {34 inode->i_op = &coda_dir_inode_operations;35 inode->i_fop = &coda_dir_operations;36 } else if (S_ISLNK(inode->i_mode)) {37 inode->i_op = &coda_symlink_inode_operations;38 inode_nohighmem(inode);39 inode->i_data.a_ops = &coda_symlink_aops;40 inode->i_mapping = &inode->i_data;41 } else42 init_special_inode(inode, inode->i_mode, huge_decode_dev(attr->va_rdev));43}44 45static int coda_test_inode(struct inode *inode, void *data)46{47 struct CodaFid *fid = (struct CodaFid *)data;48 struct coda_inode_info *cii = ITOC(inode);49 return coda_fideq(&cii->c_fid, fid);50}51 52static int coda_set_inode(struct inode *inode, void *data)53{54 struct CodaFid *fid = (struct CodaFid *)data;55 struct coda_inode_info *cii = ITOC(inode);56 cii->c_fid = *fid;57 return 0;58}59 60struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,61 struct coda_vattr * attr)62{63 struct inode *inode;64 struct coda_inode_info *cii;65 unsigned long hash = coda_f2i(fid);66 umode_t inode_type = coda_inode_type(attr);67 68retry:69 inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);70 if (!inode)71 return ERR_PTR(-ENOMEM);72 73 if (inode->i_state & I_NEW) {74 cii = ITOC(inode);75 /* we still need to set i_ino for things like stat(2) */76 inode->i_ino = hash;77 /* inode is locked and unique, no need to grab cii->c_lock */78 cii->c_mapcount = 0;79 coda_fill_inode(inode, attr);80 unlock_new_inode(inode);81 } else if ((inode->i_mode & S_IFMT) != inode_type) {82 /* Inode has changed type, mark bad and grab a new one */83 remove_inode_hash(inode);84 coda_flag_inode(inode, C_PURGE);85 iput(inode);86 goto retry;87 }88 return inode;89}90 91/* this is effectively coda_iget:92 - get attributes (might be cached)93 - get the inode for the fid using vfs iget94 - link the two up if this is needed95 - fill in the attributes96*/97struct inode *coda_cnode_make(struct CodaFid *fid, struct super_block *sb)98{99 struct coda_vattr attr;100 struct inode *inode;101 int error;102 103 /* We get inode numbers from Venus -- see venus source */104 error = venus_getattr(sb, fid, &attr);105 if (error)106 return ERR_PTR(error);107 108 inode = coda_iget(sb, fid, &attr);109 if (IS_ERR(inode))110 pr_warn("%s: coda_iget failed\n", __func__);111 return inode;112}113 114 115/* Although we treat Coda file identifiers as immutable, there is one116 * special case for files created during a disconnection where they may117 * not be globally unique. When an identifier collision is detected we118 * first try to flush the cached inode from the kernel and finally119 * resort to renaming/rehashing in-place. Userspace remembers both old120 * and new values of the identifier to handle any in-flight upcalls.121 * The real solution is to use globally unique UUIDs as identifiers, but122 * retrofitting the existing userspace code for this is non-trivial. */123void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid, 124 struct CodaFid *newfid)125{126 struct coda_inode_info *cii = ITOC(inode);127 unsigned long hash = coda_f2i(newfid);128 129 BUG_ON(!coda_fideq(&cii->c_fid, oldfid));130 131 /* replace fid and rehash inode */132 /* XXX we probably need to hold some lock here! */133 remove_inode_hash(inode);134 cii->c_fid = *newfid;135 inode->i_ino = hash;136 __insert_inode_hash(inode, hash);137}138 139/* convert a fid to an inode. */140struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb) 141{142 struct inode *inode;143 unsigned long hash = coda_f2i(fid);144 145 inode = ilookup5(sb, hash, coda_test_inode, fid);146 if ( !inode )147 return NULL;148 149 /* we should never see newly created inodes because we intentionally150 * fail in the initialization callback */151 BUG_ON(inode->i_state & I_NEW);152 153 return inode;154}155 156struct coda_file_info *coda_ftoc(struct file *file)157{158 struct coda_file_info *cfi = file->private_data;159 160 BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);161 162 return cfi;163 164}165 166/* the CONTROL inode is made without asking attributes from Venus */167struct inode *coda_cnode_makectl(struct super_block *sb)168{169 struct inode *inode = new_inode(sb);170 if (inode) {171 inode->i_ino = CTL_INO;172 inode->i_op = &coda_ioctl_inode_operations;173 inode->i_fop = &coda_ioctl_operations;174 inode->i_mode = 0444;175 return inode;176 }177 return ERR_PTR(-ENOMEM);178}179 180