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([2a02:8109:bd40:1414:c91d:59c1:64e:937b]) by smtp.gmail.com with ESMTPSA id o11-20020a17090637cb00b00926f89e2213sm1711388ejc.190.2023.03.13.06.07.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Mar 2023 06:07:43 -0700 (PDT) From: Alexander Mikhalitsyn To: corbet@lwn.net Cc: Alexander Mikhalitsyn , Eric Biggers , Miklos Szeredi , Al Viro , Christian Brauner , linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH v3 1/2] docs: filesystems: vfs: actualize struct file_system_type description Date: Mon, 13 Mar 2023 14:07:17 +0100 Message-Id: <20230313130718.253708-2-aleksandr.mikhalitsyn@canonical.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230313130718.253708-1-aleksandr.mikhalitsyn@canonical.com> References: <20230313130718.253708-1-aleksandr.mikhalitsyn@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Added descriptions for: - fscontext API ('init_fs_context' method, 'parameters' field) - 'fs_supers' field Cc: Eric Biggers Cc: Miklos Szeredi Cc: Al Viro Cc: Christian Brauner Cc: linux-fsdevel@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Alexander Mikhalitsyn Reviewed-by: Christian Brauner --- Documentation/filesystems/vfs.rst | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index 2c15e7053113..f8905ff070d0 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -107,7 +107,7 @@ file /proc/filesystems. struct file_system_type ----------------------- -This describes the filesystem. As of kernel 2.6.39, the following +This describes the filesystem. The following members are defined: .. code-block:: c @@ -115,14 +115,24 @@ members are defined: struct file_system_type { const char *name; int fs_flags; + int (*init_fs_context)(struct fs_context *); + const struct fs_parameter_spec *parameters; struct dentry *(*mount) (struct file_system_type *, int, - const char *, void *); + const char *, void *); void (*kill_sb) (struct super_block *); struct module *owner; struct file_system_type * next; - struct list_head fs_supers; + struct hlist_head fs_supers; + struct lock_class_key s_lock_key; struct lock_class_key s_umount_key; + struct lock_class_key s_vfs_rename_key; + struct lock_class_key s_writers_key[SB_FREEZE_LEVELS]; + + struct lock_class_key i_lock_key; + struct lock_class_key i_mutex_key; + struct lock_class_key invalidate_lock_key; + struct lock_class_key i_mutex_dir_key; }; ``name`` @@ -132,6 +142,15 @@ members are defined: ``fs_flags`` various flags (i.e. FS_REQUIRES_DEV, FS_NO_DCACHE, etc.) +``init_fs_context`` + Initializes 'struct fs_context' ->ops and ->fs_private fields with + filesystem-specific data. + +``parameters`` + Pointer to the array of filesystem parameters descriptors + 'struct fs_parameter_spec'. + More info in Documentation/filesystems/mount_api.rst. + ``mount`` the method to call when a new instance of this filesystem should be mounted @@ -148,7 +167,11 @@ members are defined: ``next`` for internal VFS use: you should initialize this to NULL - s_lock_key, s_umount_key: lockdep-specific +``fs_supers`` + for internal VFS use: hlist of filesystem instances (superblocks) + + s_lock_key, s_umount_key, s_vfs_rename_key, s_writers_key, + i_lock_key, i_mutex_key, invalidate_lock_key, i_mutex_dir_key: lockdep-specific The mount() method has the following arguments: