Date: Thu, 26 Jan 2017 10:49:45 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r312803 - stable/10/sys/fs/tmpfs Message-ID: <201701261049.v0QAnj4p046078@repo.freebsd.org>
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Author: kib Date: Thu Jan 26 10:49:45 2017 New Revision: 312803 URL: https://svnweb.freebsd.org/changeset/base/312803 Log: MFC r312409: Style fixes and comment updates. MFC r312435: Remove mistakenly merged field. Modified: stable/10/sys/fs/tmpfs/tmpfs.h stable/10/sys/fs/tmpfs/tmpfs_subr.c stable/10/sys/fs/tmpfs/tmpfs_vfsops.c stable/10/sys/fs/tmpfs/tmpfs_vnops.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/fs/tmpfs/tmpfs.h ============================================================================== --- stable/10/sys/fs/tmpfs/tmpfs.h Thu Jan 26 10:47:05 2017 (r312802) +++ stable/10/sys/fs/tmpfs/tmpfs.h Thu Jan 26 10:49:45 2017 (r312803) @@ -80,8 +80,10 @@ struct tmpfs_dirent { uint32_t td_hash; u_int td_namelen; - /* Pointer to the node this entry refers to. In case this field - * is NULL, the node is a whiteout. */ + /* + * Pointer to the node this entry refers to. In case this field + * is NULL, the node is a whiteout. + */ struct tmpfs_node * td_node; union { @@ -94,21 +96,24 @@ struct tmpfs_dirent { } ud; }; -/* A directory in tmpfs holds a list of directory entries, which in - * turn point to other files (which can be directories themselves). +/* + * A directory in tmpfs holds a collection of directory entries, which + * in turn point to other files (which can be directories themselves). * - * In tmpfs, this list is managed by a RB-Tree, whose head is defined by - * the struct tmpfs_dir type. + * In tmpfs, this collection is managed by a RB-Tree, whose head is + * defined by the struct tmpfs_dir type. * * It is important to notice that directories do not have entries for . and * .. as other file systems do. These can be generated when requested * based on information available by other means, such as the pointer to * the node itself in the former case or the pointer to the parent directory * in the latter case. This is done to simplify tmpfs's code and, more - * importantly, to remove redundancy. */ + * importantly, to remove redundancy. + */ RB_HEAD(tmpfs_dir, tmpfs_dirent); -/* Each entry in a directory has a cookie that identifies it. Cookies +/* + * Each entry in a directory has a cookie that identifies it. Cookies * supersede offsets within directories because, given how tmpfs stores * directories in memory, there is no such thing as an offset. * @@ -139,51 +144,65 @@ RB_HEAD(tmpfs_dir, tmpfs_dirent); * a particular type. The code must be careful to only access those * attributes that are actually allowed by the node's type. * - * * Below is the key of locks used to protected the fields in the following * structures. - * + * (v) vnode lock in exclusive mode + * (vi) vnode lock in exclusive mode, or vnode lock in shared vnode and + * tn_interlock + * (i) tn_interlock + * (m) tmpfs_mount allnode_lock + * (c) stable after creation */ struct tmpfs_node { - /* Doubly-linked list entry which links all existing nodes for a - * single file system. This is provided to ease the removal of - * all nodes during the unmount operation. */ - LIST_ENTRY(tmpfs_node) tn_entries; + /* + * Doubly-linked list entry which links all existing nodes for + * a single file system. This is provided to ease the removal + * of all nodes during the unmount operation, and to support + * the implementation of VOP_VNTOCNP(). + */ + LIST_ENTRY(tmpfs_node) tn_entries; /* (m) */ - /* The node's type. Any of 'VBLK', 'VCHR', 'VDIR', 'VFIFO', + /* + * The node's type. Any of 'VBLK', 'VCHR', 'VDIR', 'VFIFO', * 'VLNK', 'VREG' and 'VSOCK' is allowed. The usage of vnode * types instead of a custom enumeration is to make things simpler - * and faster, as we do not need to convert between two types. */ - enum vtype tn_type; + * and faster, as we do not need to convert between two types. + */ + enum vtype tn_type; /* (c) */ /* Node identifier. */ - ino_t tn_id; + ino_t tn_id; /* (c) */ - /* Node's internal status. This is used by several file system + /* + * Node's internal status. This is used by several file system * operations to do modifications to the node in a delayed - * fashion. */ - int tn_status; + * fashion. + */ + int tn_status; /* (vi) */ #define TMPFS_NODE_ACCESSED (1 << 1) #define TMPFS_NODE_MODIFIED (1 << 2) #define TMPFS_NODE_CHANGED (1 << 3) - /* The node size. It does not necessarily match the real amount - * of memory consumed by it. */ - off_t tn_size; + /* + * The node size. It does not necessarily match the real amount + * of memory consumed by it. + */ + off_t tn_size; /* (v) */ /* Generic node attributes. */ - uid_t tn_uid; - gid_t tn_gid; - mode_t tn_mode; - u_long tn_flags; - nlink_t tn_links; - struct timespec tn_atime; - struct timespec tn_mtime; - struct timespec tn_ctime; - struct timespec tn_birthtime; - unsigned long tn_gen; + uid_t tn_uid; /* (v) */ + gid_t tn_gid; /* (v) */ + mode_t tn_mode; /* (v) */ + u_long tn_flags; /* (v) */ + nlink_t tn_links; /* (v) */ + struct timespec tn_atime; /* (vi) */ + struct timespec tn_mtime; /* (vi) */ + struct timespec tn_ctime; /* (vi) */ + struct timespec tn_birthtime; /* (v) */ + unsigned long tn_gen; /* (c) */ - /* As there is a single vnode for each active file within the + /* + * As there is a single vnode for each active file within the * system, care has to be taken to avoid allocating more than one * vnode per file. In order to do this, a bidirectional association * is kept between vnodes and nodes. @@ -196,70 +215,81 @@ struct tmpfs_node { * tn_vnode. * * May be NULL when the node is unused (that is, no vnode has been - * allocated for it or it has been reclaimed). */ - struct vnode * tn_vnode; + * allocated for it or it has been reclaimed). + */ + struct vnode * tn_vnode; /* (i) */ - /* Interlock to protect tn_vpstate, and tn_status under shared + /* + * Interlock to protect tn_vpstate, and tn_status under shared * vnode lock. */ struct mtx tn_interlock; - /* Identify if current node has vnode assiocate with + /* + * Identify if current node has vnode assiocate with * or allocating vnode. */ - int tn_vpstate; + int tn_vpstate; /* (i) */ /* misc data field for different tn_type node */ union { /* Valid when tn_type == VBLK || tn_type == VCHR. */ - dev_t tn_rdev; + dev_t tn_rdev; /* (c) */ /* Valid when tn_type == VDIR. */ struct tn_dir { - /* Pointer to the parent directory. The root + /* + * Pointer to the parent directory. The root * directory has a pointer to itself in this field; - * this property identifies the root node. */ + * this property identifies the root node. + */ struct tmpfs_node * tn_parent; - /* Head of a tree that links the contents of - * the directory together. */ + /* + * Head of a tree that links the contents of + * the directory together. + */ struct tmpfs_dir tn_dirhead; - /* Head of a list the contains fake directory entries + /* + * Head of a list the contains fake directory entries * heads, i.e. entries with TMPFS_DIRCOOKIE_DUPHEAD - * flag. */ + * flag. + */ struct tmpfs_dir_duphead tn_dupindex; - /* Number and pointer of the first directory entry + /* + * Number and pointer of the first directory entry * returned by the readdir operation if it were * called again to continue reading data from the * same directory as before. This is used to speed * up reads of long directories, assuming that no * more than one read is in progress at a given time. - * Otherwise, these values are discarded. */ + * Otherwise, these values are discarded. + */ off_t tn_readdir_lastn; struct tmpfs_dirent * tn_readdir_lastp; } tn_dir; /* Valid when tn_type == VLNK. */ /* The link's target, allocated from a string pool. */ - char * tn_link; + char * tn_link; /* (c) */ /* Valid when tn_type == VREG. */ struct tn_reg { - /* The contents of regular files stored in a tmpfs - * file system are represented by a single anonymous - * memory object (aobj, for short). The aobj provides - * direct access to any position within the file, - * because its contents are always mapped in a - * contiguous region of virtual memory. It is a task - * of the memory management subsystem (see uvm(9)) to - * issue the required page ins or page outs whenever - * a position within the file is accessed. */ - vm_object_t tn_aobj; - - }tn_reg; - }tn_spec; + /* + * The contents of regular files stored in a + * tmpfs file system are represented by a + * single anonymous memory object (aobj, for + * short). The aobj provides direct access to + * any position within the file. It is a task + * of the memory management subsystem to issue + * the required page ins or page outs whenever + * a position within the file is accessed. + */ + vm_object_t tn_aobj; /* (c) */ + } tn_reg; + } tn_spec; /* (v) */ }; LIST_HEAD(tmpfs_node_list, tmpfs_node); @@ -303,26 +333,32 @@ LIST_HEAD(tmpfs_node_list, tmpfs_node); * Internal representation of a tmpfs mount point. */ struct tmpfs_mount { - /* Maximum number of memory pages available for use by the file + /* + * Maximum number of memory pages available for use by the file * system, set during mount time. This variable must never be * used directly as it may be bigger than the current amount of * free memory; in the extreme case, it will hold the ULONG_MAX - * value. */ + * value. + */ u_long tm_pages_max; /* Number of pages in use by the file system. */ u_long tm_pages_used; - /* Pointer to the node representing the root directory of this - * file system. */ + /* + * Pointer to the node representing the root directory of this + * file system. + */ struct tmpfs_node * tm_root; - /* Maximum number of possible nodes for this file system; set + /* + * Maximum number of possible nodes for this file system; set * during mount time. We need a hard limit on the maximum number * of nodes to avoid allocating too much of them; their objects * cannot be released until the file system is unmounted. * Otherwise, we could easily run out of memory by creating lots - * of empty files and then simply removing them. */ + * of empty files and then simply removing them. + */ ino_t tm_nodes_max; /* unrhdr used to allocate inode numbers */ @@ -334,27 +370,16 @@ struct tmpfs_mount { /* maximum representable file size */ u_int64_t tm_maxfilesize; - /* Nodes are organized in two different lists. The used list - * contains all nodes that are currently used by the file system; - * i.e., they refer to existing files. The available list contains - * all nodes that are currently available for use by new files. - * Nodes must be kept in this list (instead of deleting them) - * because we need to keep track of their generation number (tn_gen - * field). - * - * Note that nodes are lazily allocated: if the available list is - * empty and we have enough space to create more nodes, they will be - * created and inserted in the used list. Once these are released, - * they will go into the available list, remaining alive until the - * file system is unmounted. */ + /* + * The used list contains all nodes that are currently used by + * the file system; i.e., they refer to existing files. + */ struct tmpfs_node_list tm_nodes_used; - /* All node lock to protect the node list and tmp_pages_used */ + /* All node lock to protect the node list and tmp_pages_used. */ struct mtx allnode_lock; - /* Pools used to store file system meta data. These are not shared - * across several instances of tmpfs for the reasons described in - * tmpfs_pool.c. */ + /* Zones used to store file system meta data, per tmpfs mount. */ uma_zone_t tm_dirent_pool; uma_zone_t tm_node_pool; @@ -444,10 +469,6 @@ int tmpfs_truncate(struct vnode *, off_t } while (0) /* - * Memory management stuff. - */ - -/* * Amount of memory pages to reserve for the system (e.g., to not use by * tmpfs). */ @@ -464,37 +485,34 @@ size_t tmpfs_pages_used(struct tmpfs_mou * specific ones. */ -static inline -struct tmpfs_mount * +static inline struct tmpfs_mount * VFS_TO_TMPFS(struct mount *mp) { struct tmpfs_mount *tmp; - MPASS((mp) != NULL && (mp)->mnt_data != NULL); - tmp = (struct tmpfs_mount *)(mp)->mnt_data; - return tmp; + MPASS(mp != NULL && mp->mnt_data != NULL); + tmp = (struct tmpfs_mount *)mp->mnt_data; + return (tmp); } -static inline -struct tmpfs_node * +static inline struct tmpfs_node * VP_TO_TMPFS_NODE(struct vnode *vp) { struct tmpfs_node *node; - MPASS((vp) != NULL && (vp)->v_data != NULL); + MPASS(vp != NULL && vp->v_data != NULL); node = (struct tmpfs_node *)vp->v_data; - return node; + return (node); } -static inline -struct tmpfs_node * +static inline struct tmpfs_node * VP_TO_TMPFS_DIR(struct vnode *vp) { struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); TMPFS_VALIDATE_DIR(node); - return node; + return (node); } #endif /* _FS_TMPFS_TMPFS_H_ */ Modified: stable/10/sys/fs/tmpfs/tmpfs_subr.c ============================================================================== --- stable/10/sys/fs/tmpfs/tmpfs_subr.c Thu Jan 26 10:47:05 2017 (r312802) +++ stable/10/sys/fs/tmpfs/tmpfs_subr.c Thu Jan 26 10:49:45 2017 (r312803) @@ -198,8 +198,8 @@ tmpfs_alloc_node(struct mount *mp, struc return (EBUSY); } - nnode = (struct tmpfs_node *)uma_zalloc_arg( - tmp->tm_node_pool, tmp, M_WAITOK); + nnode = (struct tmpfs_node *)uma_zalloc_arg(tmp->tm_node_pool, tmp, + M_WAITOK); /* Generic initialization. */ nnode->tn_type = type; @@ -257,7 +257,8 @@ tmpfs_alloc_node(struct mount *mp, struc break; default: - panic("tmpfs_alloc_node: type %p %d", nnode, (int)nnode->tn_type); + panic("tmpfs_alloc_node: type %p %d", nnode, + (int)nnode->tn_type); } TMPFS_LOCK(tmp); @@ -266,25 +267,12 @@ tmpfs_alloc_node(struct mount *mp, struc TMPFS_UNLOCK(tmp); *node = nnode; - return 0; + return (0); } /* * Destroys the node pointed to by node from the file system 'tmp'. - * If the node does not belong to the given mount point, the results are - * unpredicted. - * - * If the node references a directory; no entries are allowed because - * their removal could need a recursive algorithm, something forbidden in - * kernel space. Furthermore, there is not need to provide such - * functionality (recursive removal) because the only primitives offered - * to the user are the removal of empty directories and the deletion of - * individual files. - * - * Note that nodes are not really deleted; in fact, when a node has been - * allocated, it cannot be deleted during the whole life of the file - * system. Instead, they are moved to the available list and remain there - * until reused. + * If the node references a directory, no entries are allowed. */ void tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node) @@ -609,7 +597,7 @@ loop1: VN_LOCK_ASHARE(vp); error = insmntque1(vp, mp, tmpfs_insmntque_dtr, NULL); - if (error) + if (error != 0) vp = NULL; unlock: @@ -638,7 +626,7 @@ out: } #endif - return error; + return (error); } /* @@ -706,8 +694,8 @@ tmpfs_alloc_file(struct vnode *dvp, stru /* Allocate a node that represents the new file. */ error = tmpfs_alloc_node(dvp->v_mount, tmp, vap->va_type, - cnp->cn_cred->cr_uid, - dnode->tn_gid, vap->va_mode, parent, target, vap->va_rdev, &node); + cnp->cn_cred->cr_uid, dnode->tn_gid, vap->va_mode, parent, + target, vap->va_rdev, &node); if (error != 0) return (error); @@ -1115,9 +1103,8 @@ tmpfs_dir_getdotdotdent(struct tmpfs_nod * Return ENOENT if the current node is already removed. */ TMPFS_ASSERT_LOCKED(node); - if (node->tn_dir.tn_parent == NULL) { + if (node->tn_dir.tn_parent == NULL) return (ENOENT); - } TMPFS_NODE_LOCK(node->tn_dir.tn_parent); dent.d_fileno = node->tn_dir.tn_parent->tn_id; Modified: stable/10/sys/fs/tmpfs/tmpfs_vfsops.c ============================================================================== --- stable/10/sys/fs/tmpfs/tmpfs_vfsops.c Thu Jan 26 10:47:05 2017 (r312802) +++ stable/10/sys/fs/tmpfs/tmpfs_vfsops.c Thu Jan 26 10:49:45 2017 (r312803) @@ -189,7 +189,7 @@ tmpfs_mount(struct mount *mp) /* Do not allow mounts if we do not have enough memory to preserve * the minimum reserved pages. */ if (tmpfs_mem_avail() < TMPFS_PAGES_MINRESERVED) - return ENOSPC; + return (ENOSPC); /* Get the maximum number of memory pages this file system is * allowed to use, based on the maximum size the user passed in @@ -228,27 +228,23 @@ tmpfs_mount(struct mount *mp) tmp->tm_pages_used = 0; tmp->tm_ino_unr = new_unrhdr(2, INT_MAX, &tmp->allnode_lock); tmp->tm_dirent_pool = uma_zcreate("TMPFS dirent", - sizeof(struct tmpfs_dirent), - NULL, NULL, NULL, NULL, + sizeof(struct tmpfs_dirent), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); tmp->tm_node_pool = uma_zcreate("TMPFS node", - sizeof(struct tmpfs_node), - tmpfs_node_ctor, tmpfs_node_dtor, - tmpfs_node_init, tmpfs_node_fini, - UMA_ALIGN_PTR, 0); + sizeof(struct tmpfs_node), tmpfs_node_ctor, tmpfs_node_dtor, + tmpfs_node_init, tmpfs_node_fini, UMA_ALIGN_PTR, 0); tmp->tm_ronly = (mp->mnt_flag & MNT_RDONLY) != 0; /* Allocate the root node. */ - error = tmpfs_alloc_node(mp, tmp, VDIR, root_uid, - root_gid, root_mode & ALLPERMS, NULL, NULL, - VNOVAL, &root); + error = tmpfs_alloc_node(mp, tmp, VDIR, root_uid, root_gid, + root_mode & ALLPERMS, NULL, NULL, VNOVAL, &root); if (error != 0 || root == NULL) { - uma_zdestroy(tmp->tm_node_pool); - uma_zdestroy(tmp->tm_dirent_pool); - delete_unrhdr(tmp->tm_ino_unr); - free(tmp, M_TMPFSMNT); - return error; + uma_zdestroy(tmp->tm_node_pool); + uma_zdestroy(tmp->tm_dirent_pool); + delete_unrhdr(tmp->tm_ino_unr); + free(tmp, M_TMPFSMNT); + return (error); } KASSERT(root->tn_id == 2, ("tmpfs root with invalid ino: %ju", (uintmax_t)root->tn_id)); @@ -338,12 +334,11 @@ static int tmpfs_root(struct mount *mp, int flags, struct vnode **vpp) { int error; - error = tmpfs_alloc_vp(mp, VFS_TO_TMPFS(mp)->tm_root, flags, vpp); - if (!error) + error = tmpfs_alloc_vp(mp, VFS_TO_TMPFS(mp)->tm_root, flags, vpp); + if (error == 0) (*vpp)->v_vflag |= VV_ROOT; - - return error; + return (error); } static int Modified: stable/10/sys/fs/tmpfs/tmpfs_vnops.c ============================================================================== --- stable/10/sys/fs/tmpfs/tmpfs_vnops.c Thu Jan 26 10:47:05 2017 (r312802) +++ stable/10/sys/fs/tmpfs/tmpfs_vnops.c Thu Jan 26 10:49:45 2017 (r312803) @@ -117,10 +117,12 @@ tmpfs_lookup(struct vop_cachedlookup_arg if (de != NULL && de->td_node == NULL) cnp->cn_flags |= ISWHITEOUT; if (de == NULL || de->td_node == NULL) { - /* The entry was not found in the directory. + /* + * The entry was not found in the directory. * This is OK if we are creating or renaming an * entry and are working on the last component of - * the path name. */ + * the path name. + */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == CREATE || \ cnp->cn_nameiop == RENAME || @@ -132,8 +134,10 @@ tmpfs_lookup(struct vop_cachedlookup_arg if (error != 0) goto out; - /* Keep the component name in the buffer for - * future uses. */ + /* + * Keep the component name in the buffer for + * future uses. + */ cnp->cn_flags |= SAVENAME; error = EJUSTRETURN; @@ -142,14 +146,18 @@ tmpfs_lookup(struct vop_cachedlookup_arg } else { struct tmpfs_node *tnode; - /* The entry was found, so get its associated - * tmpfs_node. */ + /* + * The entry was found, so get its associated + * tmpfs_node. + */ tnode = de->td_node; - /* If we are not at the last path component and + /* + * If we are not at the last path component and * found a non-directory or non-link entry (which * may itself be pointing to a directory), raise - * an error. */ + * an error. + */ if ((tnode->tn_type != VDIR && tnode->tn_type != VLNK) && !(cnp->cn_flags & ISLASTCN)) { @@ -157,9 +165,11 @@ tmpfs_lookup(struct vop_cachedlookup_arg goto out; } - /* If we are deleting or renaming the entry, keep + /* + * If we are deleting or renaming the entry, keep * track of its tmpfs_dirent so that it can be - * easily deleted later. */ + * easily deleted later. + */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { @@ -175,8 +185,9 @@ tmpfs_lookup(struct vop_cachedlookup_arg goto out; if ((dnode->tn_mode & S_ISTXT) && - VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, cnp->cn_thread) && - VOP_ACCESS(*vpp, VADMIN, cnp->cn_cred, cnp->cn_thread)) { + VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, + cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN, + cnp->cn_cred, cnp->cn_thread)) { error = EPERM; vput(*vpp); *vpp = NULL; @@ -192,18 +203,22 @@ tmpfs_lookup(struct vop_cachedlookup_arg } } - /* Store the result of this lookup in the cache. Avoid this if the + /* + * Store the result of this lookup in the cache. Avoid this if the * request was for creation, as it does not improve timings on - * emprical tests. */ + * emprical tests. + */ if ((cnp->cn_flags & MAKEENTRY) != 0) cache_enter(dvp, *vpp, cnp); out: - /* If there were no errors, *vpp cannot be null and it must be - * locked. */ + /* + * If there were no errors, *vpp cannot be null and it must be + * locked. + */ MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp))); - return error; + return (error); } static int @@ -1386,7 +1401,7 @@ tmpfs_whiteout(struct vop_whiteout_args } /* - * vnode operations vector used for files stored in a tmpfs file system. + * Vnode operations vector used for files stored in a tmpfs file system. */ struct vop_vector tmpfs_vnodeop_entries = { .vop_default = &default_vnodeops,
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