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1// SPDX-License-Identifier: LGPL-2.12/*3 * CIFS filesystem cache interface4 *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 */18struct 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 25static 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 35int 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 size_t slen, i;42 char *sharename;43 char *key;44 int ret = -ENOMEM;45 46 if (tcon->fscache_acquired)47 return 0;48 49 mutex_lock(&tcon->fscache_lock);50 if (tcon->fscache_acquired) {51 mutex_unlock(&tcon->fscache_lock);52 return 0;53 }54 tcon->fscache_acquired = true;55 56 tcon->fscache = NULL;57 switch (sa->sa_family) {58 case AF_INET:59 case AF_INET6:60 break;61 default:62 mutex_unlock(&tcon->fscache_lock);63 cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family);64 return -EINVAL;65 }66 67 memset(&key, 0, sizeof(key));68 69 sharename = extract_sharename(tcon->tree_name);70 if (IS_ERR(sharename)) {71 mutex_unlock(&tcon->fscache_lock);72 cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);73 return PTR_ERR(sharename);74 }75 76 slen = strlen(sharename);77 for (i = 0; i < slen; i++)78 if (sharename[i] == '/')79 sharename[i] = ';';80 81 key = kasprintf(GFP_KERNEL, "cifs,%pISpc,%s", sa, sharename);82 if (!key)83 goto out;84 85 cifs_fscache_fill_volume_coherency(tcon, &cd);86 vcookie = fscache_acquire_volume(key,87 NULL, /* preferred_cache */88 &cd, sizeof(cd));89 cifs_dbg(FYI, "%s: (%s/0x%p)\n", __func__, key, vcookie);90 if (IS_ERR(vcookie)) {91 if (vcookie != ERR_PTR(-EBUSY)) {92 ret = PTR_ERR(vcookie);93 goto out_2;94 }95 pr_err("Cache volume key already in use (%s)\n", key);96 vcookie = NULL;97 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,98 netfs_trace_tcon_ref_see_fscache_collision);99 } else {100 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,101 netfs_trace_tcon_ref_see_fscache_okay);102 }103 104 tcon->fscache = vcookie;105 ret = 0;106out_2:107 kfree(key);108out:109 kfree(sharename);110 mutex_unlock(&tcon->fscache_lock);111 return ret;112}113 114void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)115{116 struct cifs_fscache_volume_coherency_data cd;117 118 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);119 120 cifs_fscache_fill_volume_coherency(tcon, &cd);121 fscache_relinquish_volume(tcon->fscache, &cd, false);122 tcon->fscache = NULL;123 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,124 netfs_trace_tcon_ref_see_fscache_relinq);125}126 127void cifs_fscache_get_inode_cookie(struct inode *inode)128{129 struct cifs_fscache_inode_coherency_data cd;130 struct cifs_fscache_inode_key key;131 struct cifsInodeInfo *cifsi = CIFS_I(inode);132 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);133 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);134 135 key.uniqueid = cpu_to_le64(cifsi->uniqueid);136 key.createtime = cpu_to_le64(cifsi->createtime);137 key.type = (inode->i_mode & S_IFMT) >> 12;138 cifs_fscache_fill_coherency(&cifsi->netfs.inode, &cd);139 140 cifsi->netfs.cache =141 fscache_acquire_cookie(tcon->fscache, 0,142 &key, sizeof(key),143 &cd, sizeof(cd),144 i_size_read(&cifsi->netfs.inode));145 if (cifsi->netfs.cache)146 mapping_set_release_always(inode->i_mapping);147}148 149void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update)150{151 if (update) {152 struct cifs_fscache_inode_coherency_data cd;153 loff_t i_size = i_size_read(inode);154 155 cifs_fscache_fill_coherency(inode, &cd);156 fscache_unuse_cookie(cifs_inode_cookie(inode), &cd, &i_size);157 } else {158 fscache_unuse_cookie(cifs_inode_cookie(inode), NULL, NULL);159 }160}161 162void cifs_fscache_release_inode_cookie(struct inode *inode)163{164 struct cifsInodeInfo *cifsi = CIFS_I(inode);165 struct fscache_cookie *cookie = cifs_inode_cookie(inode);166 167 if (cookie) {168 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cookie);169 fscache_relinquish_cookie(cookie, false);170 cifsi->netfs.cache = NULL;171 }172}173