1 // SPDX-License-Identifier: LGPL-2.1 2 /* 3 * CIFS filesystem cache interface 4 * 5 * Copyright (c) 2010 Novell, Inc. 6 * Author(s): Suresh Jayaraman <sjayaraman@suse.de> 7 * 8 */ 9 #include "fscache.h" 10 #include "cifsglob.h" 11 #include "cifs_debug.h" 12 #include "cifs_fs_sb.h" 13 #include "cifsproto.h" 14 15 /* 16 * Key for fscache inode. [!] Contents must match comparisons in cifs_find_inode(). 17 */ 18 struct cifs_fscache_inode_key { 19 20 __le64 uniqueid; /* server inode number */ 21 __le64 createtime; /* creation time on server */ 22 u8 type; /* S_IFMT file type */ 23 } __packed; 24 25 static void cifs_fscache_fill_volume_coherency( 26 struct cifs_tcon *tcon, 27 struct cifs_fscache_volume_coherency_data *cd) 28 { 29 memset(cd, 0, sizeof(*cd)); 30 cd->resource_id = cpu_to_le64(tcon->resource_id); 31 cd->vol_create_time = tcon->vol_create_time; 32 cd->vol_serial_number = cpu_to_le32(tcon->vol_serial_number); 33 } 34 35 int cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) 36 { 37 struct cifs_fscache_volume_coherency_data cd; 38 struct TCP_Server_Info *server = tcon->ses->server; 39 struct fscache_volume *vcookie; 40 const struct sockaddr *sa = (struct sockaddr *)&server->dstaddr; 41 char *sharename; 42 char *key; 43 int ret = -ENOMEM; 44 45 if (tcon->fscache_acquired) 46 return 0; 47 48 mutex_lock(&tcon->fscache_lock); 49 if (tcon->fscache_acquired) { 50 mutex_unlock(&tcon->fscache_lock); 51 return 0; 52 } 53 tcon->fscache_acquired = true; 54 55 tcon->fscache = NULL; 56 switch (sa->sa_family) { 57 case AF_INET: 58 case AF_INET6: 59 break; 60 default: 61 mutex_unlock(&tcon->fscache_lock); 62 cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family); 63 return -EINVAL; 64 } 65 66 memset(&key, 0, sizeof(key)); 67 68 sharename = extract_sharename(tcon->tree_name); 69 if (IS_ERR(sharename)) { 70 mutex_unlock(&tcon->fscache_lock); 71 cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__); 72 return PTR_ERR(sharename); 73 } 74 75 strreplace(sharename, '/', ';'); 76 77 key = kasprintf(GFP_KERNEL, "cifs,%pISpc,%s", sa, sharename); 78 if (!key) 79 goto out; 80 81 cifs_fscache_fill_volume_coherency(tcon, &cd); 82 vcookie = fscache_acquire_volume(key, 83 NULL, /* preferred_cache */ 84 &cd, sizeof(cd)); 85 cifs_dbg(FYI, "%s: (%s/0x%p)\n", __func__, key, vcookie); 86 if (IS_ERR(vcookie)) { 87 if (vcookie != ERR_PTR(-EBUSY)) { 88 ret = PTR_ERR(vcookie); 89 goto out_2; 90 } 91 pr_err("Cache volume key already in use (%s)\n", key); 92 vcookie = NULL; 93 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, 94 netfs_trace_tcon_ref_see_fscache_collision); 95 } else { 96 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, 97 netfs_trace_tcon_ref_see_fscache_okay); 98 } 99 100 tcon->fscache = vcookie; 101 ret = 0; 102 out_2: 103 kfree(key); 104 out: 105 kfree(sharename); 106 mutex_unlock(&tcon->fscache_lock); 107 return ret; 108 } 109 110 void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) 111 { 112 struct cifs_fscache_volume_coherency_data cd; 113 114 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache); 115 116 cifs_fscache_fill_volume_coherency(tcon, &cd); 117 fscache_relinquish_volume(tcon->fscache, &cd, false); 118 tcon->fscache = NULL; 119 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, 120 netfs_trace_tcon_ref_see_fscache_relinq); 121 } 122 123 void cifs_fscache_get_inode_cookie(struct inode *inode) 124 { 125 struct cifs_fscache_inode_coherency_data cd; 126 struct cifs_fscache_inode_key key; 127 struct cifsInodeInfo *cifsi = CIFS_I(inode); 128 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); 129 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb); 130 131 key.uniqueid = cpu_to_le64(cifsi->uniqueid); 132 key.createtime = cpu_to_le64(cifsi->createtime); 133 key.type = (inode->i_mode & S_IFMT) >> 12; 134 cifs_fscache_fill_coherency(&cifsi->netfs.inode, &cd); 135 136 cifsi->netfs.cache = 137 fscache_acquire_cookie(tcon->fscache, 0, 138 &key, sizeof(key), 139 &cd, sizeof(cd), 140 i_size_read(&cifsi->netfs.inode)); 141 if (cifsi->netfs.cache) 142 mapping_set_release_always(inode->i_mapping); 143 } 144 145 void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update) 146 { 147 if (update) { 148 struct cifs_fscache_inode_coherency_data cd; 149 loff_t i_size = i_size_read(inode); 150 151 cifs_fscache_fill_coherency(inode, &cd); 152 fscache_unuse_cookie(cifs_inode_cookie(inode), &cd, &i_size); 153 } else { 154 fscache_unuse_cookie(cifs_inode_cookie(inode), NULL, NULL); 155 } 156 } 157 158 void cifs_fscache_release_inode_cookie(struct inode *inode) 159 { 160 struct cifsInodeInfo *cifsi = CIFS_I(inode); 161 struct fscache_cookie *cookie = cifs_inode_cookie(inode); 162 163 if (cookie) { 164 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cookie); 165 fscache_relinquish_cookie(cookie, false); 166 cifsi->netfs.cache = NULL; 167 } 168 } 169