Add cifs_match_super to use in sget to share superblock between mounts that have the same //server/sharename, credentials and mount options. It helps us to improve performance on work with future SMB2.1 leases.
Signed-off-by: Pavel Shilovsky <[email protected]> --- fs/cifs/cifsfs.c | 18 ++++++++++- fs/cifs/cifsglob.h | 5 +++ fs/cifs/connect.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 112 insertions(+), 1 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 446b5c2..ba0b7ae 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -644,6 +644,7 @@ cifs_do_mount(struct file_system_type *fs_type, struct super_block *sb; struct cifs_sb_info *cifs_sb; struct smb_vol *volume_info; + struct cifs_mnt_data mnt_data; struct dentry *root; char *copied_data = NULL; @@ -661,13 +662,21 @@ cifs_do_mount(struct file_system_type *fs_type, cifs_setup_cifs_sb(volume_info, cifs_sb); - sb = sget(fs_type, NULL, set_anon_super, NULL); + mnt_data.vol = volume_info; + mnt_data.cifs_sb = cifs_sb; + + sb = sget(fs_type, cifs_match_super, set_anon_super, &mnt_data); if (IS_ERR(sb)) { kfree(cifs_sb); root = ERR_CAST(sb); goto out; } + if (sb->s_fs_info) { + cFYI(1, "Use existing superblock"); + goto out_shared; + } + sb->s_flags = flags; /* @@ -700,6 +709,13 @@ out: cifs_cleanup_volume_info(&volume_info); return root; +out_shared: + root = cifs_get_root(volume_info, sb); + if (root) + cFYI(1, "dentry root is: %p", root); + cifs_cleanup_volume_info(&volume_info); + return root; + err_out: kfree(cifs_sb); deactivate_locked_super(sb); diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 7ad7d69..55901b0 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -211,6 +211,11 @@ struct smb_vol { struct nls_table *local_nls; }; +struct cifs_mnt_data { + struct cifs_sb_info *cifs_sb; + struct smb_vol *vol; +}; + struct TCP_Server_Info { struct list_head tcp_ses_list; struct list_head smb_ses_list; diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 1cacfaa..1d39dcf 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2135,6 +2135,96 @@ cifs_put_tlink(struct tcon_link *tlink) return; } +static inline struct tcon_link * +cifs_sb_master_tlink(struct cifs_sb_info *cifs_sb); + +static const u32 ACTUAL_MOUNT_FLAGS = CIFS_MOUNT_NO_PERM | CIFS_MOUNT_SET_UID | + CIFS_MOUNT_SERVER_INUM | CIFS_MOUNT_DIRECT_IO | CIFS_MOUNT_NO_XATTR | + CIFS_MOUNT_MAP_SPECIAL_CHR | CIFS_MOUNT_UNX_EMUL | CIFS_MOUNT_NO_BRL | + CIFS_MOUNT_CIFS_ACL | CIFS_MOUNT_OVERR_UID | CIFS_MOUNT_OVERR_GID | + CIFS_MOUNT_DYNPERM | CIFS_MOUNT_NOPOSIXBRL | CIFS_MOUNT_NOSSYNC | + CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | CIFS_MOUNT_MULTIUSER | + CIFS_MOUNT_STRICT_IO; + +static int +compare_mount_options(struct cifs_sb_info *old, struct cifs_sb_info *new) +{ + if ((old->mnt_cifs_flags & ACTUAL_MOUNT_FLAGS) != + (new->mnt_cifs_flags & ACTUAL_MOUNT_FLAGS)) + return 0; + + if (old->rsize != new->rsize || old->wsize != new->wsize) + return 0; + + if (old->mnt_uid != new->mnt_uid || old->mnt_gid != new->mnt_gid) + return 0; + + if (old->mnt_file_mode != new->mnt_file_mode || + old->mnt_dir_mode != new->mnt_dir_mode) + return 0; + + if (strcmp(old->local_nls->charset, new->local_nls->charset)) + return 0; + + if (old->actimeo != new->actimeo) + return 0; + + return 1; +} + +int +cifs_match_super(struct super_block *sb, void *data) +{ + struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data; + struct smb_vol *volume_info; + struct cifs_sb_info *cifs_sb, *new_cifs_sb; + struct TCP_Server_Info *tcp_srv; + struct cifsSesInfo *ses; + struct cifsTconInfo *tcon; + struct tcon_link *tlink; + struct sockaddr_storage addr; + int rc = 0; + + memset(&addr, 0, sizeof(struct sockaddr_storage)); + + spin_lock(&cifs_tcp_ses_lock); + cifs_sb = CIFS_SB(sb); + tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb)); + if (IS_ERR(tlink)) { + spin_unlock(&cifs_tcp_ses_lock); + return rc; + } + tcon = tlink_tcon(tlink); + ses = tcon->ses; + tcp_srv = ses->server; + + volume_info = mnt_data->vol; + new_cifs_sb = mnt_data->cifs_sb; + + if (!volume_info->UNCip || !volume_info->UNC) + goto out; + + rc = cifs_fill_sockaddr((struct sockaddr *)&addr, + volume_info->UNCip, + strlen(volume_info->UNCip), + volume_info->port); + if (!rc) + goto out; + + if (!match_server(tcp_srv, (struct sockaddr *)&addr, volume_info) || + !match_session(ses, volume_info) || + !match_tcon(tcon, volume_info->UNC)) { + rc = 0; + goto out; + } + + rc = compare_mount_options(cifs_sb, new_cifs_sb); +out: + cifs_put_tlink(tlink); + spin_unlock(&cifs_tcp_ses_lock); + return rc; +} + int get_dfs_path(int xid, struct cifsSesInfo *pSesInfo, const char *old_path, const struct nls_table *nls_codepage, unsigned int *pnum_referrals, -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
