smb_tree.c revision 55bf511df53aad0fdb7eb3fa349f0308cc05234c
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * CDDL HEADER START
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da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * CDDL HEADER END
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Use is subject to license terms.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw#pragma ident "%Z%%M% %I% %E% SMI"
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * General Structures Layout
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * -------------------------
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This is a simplified diagram showing the relationship between most of the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * main structures.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | SMB_INFO |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | SESSION |<----->| SESSION |......| SESSION |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | USER |<----->| USER |......| USER |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | TREE |<----->| TREE |......| TREE |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------------------+ +-------------------+ +-------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | +-------+ +-------+ +-------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | | OFILE |<----->| OFILE |......| OFILE |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | +-------+ +-------+ +-------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------+ +------+ +------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | ODIR |<----->| ODIR |......| ODIR |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-------+ +------+ +------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Tree State Machine
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * ------------------
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-----------------------------+ T0
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | SMB_TREE_STATE_CONNECTED |<----------- Creation/Allocation
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-----------------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +------------------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | SMB_TREE_STATE_DISCONNECTING |
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +------------------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-----------------------------+ T3
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * | SMB_TREE_STATE_DISCONNECTED |----------> Deletion/Free
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * +-----------------------------+
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * SMB_TREE_STATE_CONNECTED
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * While in this state:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The tree is queued in the list of trees of its user.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - References will be given out if the tree is looked up.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - Files under that tree can be accessed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * SMB_TREE_STATE_DISCONNECTING
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * While in this state:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The tree is queued in the list of trees of its user.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - References will not be given out if the tree is looked up.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The files and directories open under the tree are being closed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The resources associated with the tree remain.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * SMB_TREE_STATE_DISCONNECTED
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * While in this state:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The tree is queued in the list of trees of its user.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - References will not be given out if the tree is looked up.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The tree has no more files and directories opened.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The resources associated with the tree remain.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Transition T0
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This transition occurs in smb_tree_connect(). A new tree is created and
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * added to the list of trees of a user.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Transition T1
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This transition occurs in smb_tree_disconnect().
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Transition T2
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This transition occurs in smb_tree_release(). The resources associated
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * with the tree are freed as well as the tree structure. For the transition
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * to occur, the tree must be in the SMB_TREE_STATE_DISCONNECTED state and
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the reference count be zero.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Comments
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * --------
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The state machine of the tree structures is controlled by 3 elements:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The list of trees of the user it belongs to.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The mutex embedded in the structure itself.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * - The reference count.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * There's a mutex embedded in the tree structure used to protect its fields
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * and there's a lock embedded in the list of trees of a user. To
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * increment or to decrement the reference count the mutex must be entered.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * To insert the tree into the list of trees of the user and to remove
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the tree from it, the lock must be entered in RW_WRITER mode.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Rules of access to a tree structure:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * 1) In order to avoid deadlocks, when both (mutex and lock of the user
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * list) have to be entered, the lock must be entered first.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * 2) All actions applied to a tree require a reference count.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * 3) There are 2 ways of getting a reference count. One is when the tree
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * is connected. The other when the user is looked up. This translates
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * into 2 functions: smb_tree_connect() and smb_tree_lookup_by_tid().
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * It should be noted that the reference count of a tree registers the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * number of references to the tree in other structures (such as an smb
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * request). The reference count is not incremented in these 2 instances:
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * 1) The tree is connected. An tree is anchored by his state. If there's
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * no activity involving a tree currently connected, the reference
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * count of that tree is zero.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * 2) The tree is queued in the list of trees of the user. The fact of
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * being queued in that list is NOT registered by incrementing the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * reference count.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw/* Static functions defined further down this file. */
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amwstatic smb_tree_t *smb_tree_lookup_next(smb_llist_t *, smb_tree_t *);
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_connect
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw tree = kmem_cache_alloc(smb_info.si_cache_tree, KM_SLEEP);
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw smb_llist_constructor(&tree->t_ofile_list, sizeof (smb_ofile_t),
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw smb_llist_constructor(&tree->t_odir_list, sizeof (smb_odir_t),
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw (void) strlcpy(tree->t_resource, resource, sizeof (tree->t_resource));
55bf511df53aad0fdb7eb3fa349f0308cc05234cas if (strncasecmp(tree->t_typename, NFS, sizeof (NFS)) == 0)
55bf511df53aad0fdb7eb3fa349f0308cc05234cas if (strncasecmp(tree->t_typename, "UFS", sizeof ("UFS")) == 0)
55bf511df53aad0fdb7eb3fa349f0308cc05234cas if (vfs_has_feature(snode->vp->v_vfsp, VFSFT_ACLONCREATE))
55bf511df53aad0fdb7eb3fa349f0308cc05234cas if (vfs_has_feature(snode->vp->v_vfsp, VFSFT_ACEMASKONACCESS))
55bf511df53aad0fdb7eb3fa349f0308cc05234cas if (vfs_has_feature(snode->vp->v_vfsp, VFSFT_CASEINSENSITIVE))
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_disconnect
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The tree is moved into a state indicating that the disconnect
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * process has started.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The files opened under this tree are closed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The directories opened under this tree are closed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw /*FALLTHRU*/
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_disconnect_all
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_close_all_by_pid
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_release
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Find the appropriate tree for this request. The request credentials
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * set here override those set during uid lookup. In domain mode, the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * user and tree credentials should be the same. In share mode, the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * tree credentials (defined in the share definition) should override
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the user credentials.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw /* The tree exists and is still connected. */
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The tree exists but is diconnected or is in
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the process of being destroyed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_lookup_first_by_name
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This function returns the first tree in the connected state that matches the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * sharename passed in. If the tree provided is NULL the search starts from
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the beginning of the list of trees of the user. It a tree is provided the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * search starts just after that tree.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw /* The tree exists and is still connected. */
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The tree exists but is diconnected or is in
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the process of being destroyed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_lookup_first_by_fsd
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This function returns the first tree in the connected state that matches the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * fsd passed in. If the tree provided is NULL the search starts from
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the beginning of the list of trees of the user. It a tree is provided the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * search starts just after that tree.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw /* The tree exists and is still connected. */
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The tree exists but is diconnected or is in
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * the process of being destroyed.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw/* *************************** Static Functions ***************************** */
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_delete
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This function releases all the resources associated with a tree. It also
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * removes the tree the caller passes from the list of trees of the user.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The tree to destroy must be in the "destroying state" and the reference count
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * must be zero. This function assumes it's single threaded i.e. only one
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * thread will attempt to destroy a specific tree (this condition should be met
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * if the tree is is the "destroying state" and has a reference count of zero).
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * tree Tree to destroy
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amwstatic void
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * Let's remove the tree from the list of trees of the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * user. This has to be done before any resources
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * associated with the tree are released.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw smb_idpool_free(&tree->t_user->u_tid_pool, tree->t_tid);
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * The list of open files and open directories should be empty.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_lookup_head
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This function returns the first tree in the list that is in the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * SMB_TREE_STATE_CONNECTED. A reference is taken on the tree and
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_release() will have to be called for the tree returned.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * lst List of trees (usually the list of trees of a user)
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * NULL No tree in the SMB_TREE_STATE_CONNECTED state was found.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * !NULL First tree in the list in the SMB_TREE_STATE_CONNECTED state.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw } else if ((tree->t_state == SMB_TREE_STATE_DISCONNECTING) ||
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_lookup_next
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * This function returns the next tree in the list that is in the
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * SMB_TREE_STATE_CONNECTED. A reference is taken on the tree and
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * smb_tree_release() will have to be called for the tree returned.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * lst List of trees (usually the list of trees of a user).
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * tree Starting tree.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * NULL No tree in the SMB_TREE_STATE_CONNECTED state was found.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw * !NULL Next tree in the list in the SMB_TREE_STATE_CONNECTED state.
da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0amw } else if ((next->t_state == SMB_TREE_STATE_DISCONNECTING) ||