+++ /dev/null
-/*
- * This Cplant(TM) source code is the property of Sandia National
- * Laboratories.
- *
- * This Cplant(TM) source code is copyrighted by Sandia National
- * Laboratories.
- *
- * The redistribution of this Cplant(TM) source code is subject to the
- * terms of the GNU Lesser General Public License
- * (see cit/LGPL or http://www.gnu.org/licenses/lgpl.html)
- *
- * Cplant(TM) Copyright 1998-2006 Sandia Corporation.
- * Under the terms of Contract DE-AC04-94AL85000, there is a non-exclusive
- * license for use of this work by or on behalf of the US Government.
- * Export of this program may require a license from the United States
- * Government.
- */
-
-/*
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * Questions or comments about this library should be sent to:
- *
- * Lee Ward
- * Sandia National Laboratories, New Mexico
- * P.O. Box 5800
- * Albuquerque, NM 87185-1110
- *
- * lee@sandia.gov
- */
-
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <assert.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/queue.h>
-
-#include "sysio.h"
-#include "fs.h"
-#include "mount.h"
-#include "inode.h"
-#include "dev.h"
-
-/*
- * Support for path and index nodes.
- */
-
-/*
- * Size of all names bucket-hash table.
- */
-#ifndef NAMES_TABLE_LEN
-#define NAMES_TABLE_LEN 251
-#endif
-
-/*
- * Desired i-nodes cache size is MAX_INODES_MULTIPLIER times the number
- * of slots in the names hash table.
- */
-#define MAX_INODES_MULTIPLIER 3
-
-/*
- * Active i-nodes in the system and the number of same.
- */
-struct inodes_head _sysio_inodes;
-static size_t n_inodes = 0;
-/*
- * Desired number of active i-nodes.
- */
-static size_t max_inodes = (MAX_INODES_MULTIPLIER * NAMES_TABLE_LEN);
-
-/*
- * System table for rapid access to component names.
- */
-static LIST_HEAD(, pnode_base) names[NAMES_TABLE_LEN];
-/*
- * Number of names tracked by the system.
- */
-static size_t n_names = 0;
-/*
- * Desired number of base path nodes to maintain.
- */
-static size_t max_names = (2 * NAMES_TABLE_LEN);
-
-/*
- * Number of pnodes to grab per memory allocation when filling the
- * free list.
- */
-#define PNODES_PER_CHUNK ((8 * 1024) / sizeof(struct pnode) - 2)
-
-#ifdef ZERO_SUM_MEMORY
-/*
- * Allocation information for pnodes bulk allocation.
- */
-struct pnodes_block {
- LIST_ENTRY(pnodes_block) pnblk_links;
- struct pnode pnblk_nodes[PNODES_PER_CHUNK];
-};
-
-static LIST_HEAD( ,pnodes_block) pnblocks;
-#endif
-
-/*
- * List of all path-nodes (aliases) referenced by any tree.
- */
-struct pnodes_head _sysio_pnodes;
-
-/*
- * Free path-nodes -- Not referenced by any tree for fas reuse.
- */
-static LIST_HEAD( ,pnode) free_pnodes;
-
-/*
- * The system root -- Aka `/'.
- */
-struct pnode *_sysio_root = NULL;
-
-/*
- * Initialize path and i-node support. Must be called before any other
- * routine in this module.
- */
-int
-_sysio_i_init()
-{
- unsigned i;
-
- TAILQ_INIT(&_sysio_inodes);
-
- for (i = 0; i < NAMES_TABLE_LEN; i++)
- LIST_INIT(&names[i]);
-
-#ifdef ZERO_SUM_MEMORY
- LIST_INIT(&pnblocks);
-#endif
- TAILQ_INIT(&_sysio_pnodes);
- LIST_INIT(&free_pnodes);
-
- return 0;
-}
-
-/*
- * Garbage-collect idle i-nodes. We try to keep resource use limited to
- * MAX_INODES_MULTIPLIER * max_names.
- */
-static void
-i_reclaim()
-{
- struct inode *next, *ino;
- size_t t;
-
- /*
- * I just can't figure out a good way to reclaim these well without
- * getting really fancy and using complex algorithms. The
- * base nodes hold references on them for a long time and then
- * release them. Those will age to the front of the queue and
- * we have to skip over them. Oh well...
- */
- t = MAX_INODES_MULTIPLIER * max_names;
- if (max_inodes < t) {
- /*
- * Oops. Nope. We want more inodes than names entries.
- */
- max_inodes = t;
- return;
- }
- next = _sysio_inodes.tqh_first;
- if (!next)
- return;
- t = max_inodes / 2;
- do {
- ino = next;
- next = ino->i_nodes.tqe_next;
- if (ino->i_ref || ino->i_immune)
- continue;
- _sysio_i_gone(ino);
- } while (next && n_inodes > t);
-
- if (n_inodes > t)
- max_inodes += t;
-}
-
-static unsigned
-hash(struct file_identifier *fid)
-{
- size_t n;
- unsigned char *ucp;
- unsigned hkey;
-
- n = fid->fid_len;
- ucp = fid->fid_data;
- hkey = 0;
- do {
- hkey <<= 1;
- hkey += *ucp++;
- } while (--n);
- return hkey;
-}
-
-/*
- * Allocate and initialize a new i-node. Returned i-node is referenced.
- *
- * NB: The passed file identifier is not copied. It is, therefor, up to the
- * caller to assure that the value is static until the inode is destroyed.
- */
-struct inode *
-_sysio_i_new(struct filesys *fs,
- struct file_identifier *fid,
- struct intnl_stat *stat,
- unsigned immunity,
- struct inode_ops *ops,
- void *private)
-{
- struct inode *ino;
- struct itable_entry *head;
- struct inode_ops operations;
-
- if (n_inodes > max_inodes) {
- /*
- * Try to limit growth.
- */
- i_reclaim();
- }
-
- ino = malloc(sizeof(struct inode));
- if (!ino)
- return NULL;
- ino->i_ops = *ops;
- operations = *ops;
- if (S_ISBLK(stat->st_mode) ||
- S_ISCHR(stat->st_mode) ||
- S_ISFIFO(stat->st_mode)) {
- struct inode_ops *o;
-
- /*
- * Replace some operations sent with
- * those from the device table.
- */
- o = _sysio_dev_lookup(stat->st_mode, stat->st_rdev);
- operations.inop_open = o->inop_open;
- operations.inop_close = o->inop_close;
- operations.inop_read = o->inop_read;
- operations.inop_write = o->inop_write;
- operations.inop_pos = o->inop_pos;
- operations.inop_iodone = o->inop_iodone;
- operations.inop_fcntl = o->inop_fcntl;
- operations.inop_datasync = o->inop_datasync;
- operations.inop_ioctl = o->inop_ioctl;
- }
- I_INIT(ino, fs, stat, &operations, fid, immunity, private);
- ino->i_ref = 1;
- TAILQ_INSERT_TAIL(&_sysio_inodes, ino, i_nodes);
- head = &fs->fs_itbl[hash(fid) % FS_ITBLSIZ];
- LIST_INSERT_HEAD(head, ino, i_link);
-
- n_inodes++;
- assert(n_inodes);
-
- return ino;
-}
-
-/*
- * Find existing i-node given i-number and pointers to FS record
- * and identifier.
- */
-struct inode *
-_sysio_i_find(struct filesys *fs, struct file_identifier *fid)
-{
- struct inode *ino;
- struct itable_entry *head;
-
- head = &fs->fs_itbl[hash(fid) % FS_ITBLSIZ];
- /*
- * Look for existing.
- */
- for (ino = head->lh_first; ino; ino = ino->i_link.le_next)
- if (ino->i_fid->fid_len == fid->fid_len &&
- memcmp(ino->i_fid->fid_data,
- fid->fid_data,
- fid->fid_len) == 0) {
- I_REF(ino);
- break;
- }
-
- return ino;
-}
-
-/*
- * Force reclaim of idle i-node.
- */
-void
-_sysio_i_gone(struct inode *ino)
-{
-
- if (ino->i_ref)
- abort();
- if (!ino->i_zombie)
- LIST_REMOVE(ino, i_link);
- TAILQ_REMOVE(&_sysio_inodes, ino, i_nodes);
- (*ino->i_ops.inop_gone)(ino);
- free(ino);
-
- assert(n_inodes);
- n_inodes--;
-}
-
-/*
- * Stale inode, zombie it and move it out of the way
- */
-void
-_sysio_i_undead(struct inode *ino)
-{
-
- if (ino->i_zombie)
- return;
- LIST_REMOVE(ino, i_link);
- ino->i_zombie = 1;
-}
-
-/*
- * Garbage collect idle path (and base path) nodes tracked by the system.
- */
-static void
-p_reclaim()
-{
- struct pnode *next, *pno;
- size_t t;
-
- next = _sysio_pnodes.tqh_first;
- if (!next)
- return;
- t = max_names / 2;
- do {
- pno = next;
- if (pno->p_ref) {
- next = pno->p_nodes.tqe_next;
- continue;
- }
- pno->p_ref++;
- assert(pno->p_ref);
- (void )_sysio_p_prune(pno);
- next = pno->p_nodes.tqe_next;
- assert(pno->p_ref);
- pno->p_ref--;
- if (pno->p_ref)
- continue;
- (void )_sysio_p_prune(pno);
- } while (n_names > t && next);
-
- if (n_names > t)
- max_names += t;
-}
-
-/*
- * Allocate and initialize a new base path node.
- */
-struct pnode_base *
-_sysio_pb_new(struct qstr *name, struct pnode_base *parent, struct inode *ino)
-{
- struct pnode_base *pb;
-
- if (n_names > max_names) {
- /*
- * Try to limit growth.
- */
- p_reclaim();
- }
-
- pb = malloc(sizeof(struct pnode_base) + name->len);
- if (!pb)
- return NULL;
-
- pb->pb_name.name = NULL;
- pb->pb_name.len = name->len;
- if (pb->pb_name.len) {
- char *cp;
-
- /*
- * Copy the passed name.
- *
- * We have put the space for the name immediately behind
- * the record in order to maximize spatial locality.
- */
- cp = (char *)pb + sizeof(struct pnode_base);
- (void )strncpy(cp, name->name, name->len);
- pb->pb_name.name = cp;
- assert(name->hashval);
- pb->pb_name.hashval = name->hashval;
- LIST_INSERT_HEAD(&names[name->hashval % NAMES_TABLE_LEN],
- pb,
- pb_names);
- }
- pb->pb_ino = ino;
- LIST_INIT(&pb->pb_children);
- LIST_INIT(&pb->pb_aliases);
- if (parent)
- LIST_INSERT_HEAD(&parent->pb_children, pb, pb_sibs);
- pb->pb_parent = parent;
-
- n_names++;
- assert(n_names);
-
- return pb;
-}
-
-/*
- * Destroy base path node, releasing resources back to the system.
- *
- * NB: Caller must release the inode referenced by the record.
- */
-static void
-pb_destroy(struct pnode_base *pb)
-{
-
- assert(n_names);
- n_names--;
-
- assert(!pb->pb_aliases.lh_first);
- assert(!pb->pb_children.lh_first);
- assert(!pb->pb_ino);
- if (pb->pb_name.len)
- LIST_REMOVE(pb, pb_names);
- if (pb->pb_parent)
- LIST_REMOVE(pb, pb_sibs);
-
-#ifndef NDEBUG
- /*
- * This can help us catch pb-nodes that are free'd redundantly.
- */
- pb->pb_name.hashval = 0;
-#endif
- free(pb);
-}
-
-/*
- * Force reclaim of idle base path node.
- */
-void
-_sysio_pb_gone(struct pnode_base *pb)
-{
-
- if (pb->pb_ino)
- I_RELE(pb->pb_ino);
- pb->pb_ino = NULL;
-
- pb_destroy(pb);
-}
-
-/*
- * Generate more path (alias) nodes for the fast allocator.
- */
-static void
-more_pnodes()
-{
- size_t n;
-#ifdef ZERO_SUM_MEMORY
- struct pnodes_block *pnblk;
-#endif
- struct pnode *pno;
-
-#ifdef ZERO_SUM_MEMORY
- pnblk = malloc(sizeof(struct pnodes_block));
- pno = NULL;
- if (pnblk) {
- LIST_INSERT_HEAD(&pnblocks, pnblk, pnblk_links);
- pno = pnblk->pnblk_nodes;
- }
-#else
- pno = malloc(PNODES_PER_CHUNK * sizeof(struct pnode));
-#endif
- if (!pno)
- return;
- n = PNODES_PER_CHUNK;
- do {
- LIST_INSERT_HEAD(&free_pnodes, pno, p_links);
- pno++;
- } while (--n);
-}
-
-#ifdef ZERO_SUM_MEMORY
-/*
- * Shutdown
- */
-void
-_sysio_i_shutdown()
-{
- struct pnodes_block *pnblk;
-
- while ((pnblk = pnblocks.lh_first)) {
- LIST_REMOVE(pnblk, pnblk_links);
- free(pnblk);
- }
-}
-#endif
-
-/*
- * Allocate, initialize and establish appropriate links for new path (alias)
- * node.
- */
-struct pnode *
-_sysio_p_new_alias(struct pnode *parent,
- struct pnode_base *pb,
- struct mount *mnt)
-{
- struct pnode *pno;
-
- assert(!pb->pb_name.name || pb->pb_name.hashval);
-
- pno = free_pnodes.lh_first;
- if (!pno) {
- more_pnodes();
- pno = free_pnodes.lh_first;
- }
- if (!pno)
- return NULL;
- LIST_REMOVE(pno, p_links);
-
- pno->p_ref = 1;
- pno->p_parent = parent;
- if (!pno->p_parent)
- pno->p_parent = pno;
- pno->p_base = pb;
- pno->p_mount = mnt;
- pno->p_cover = NULL;
- LIST_INSERT_HEAD(&pb->pb_aliases, pno, p_links);
- TAILQ_INSERT_TAIL(&_sysio_pnodes, pno, p_nodes);
-
- return pno;
-}
-
-/*
- * For reclamation of idle path (alias) node.
- */
-void
-_sysio_p_gone(struct pnode *pno)
-{
- struct pnode_base *pb;
-
- assert(!pno->p_ref);
- assert(!pno->p_cover);
-
- TAILQ_REMOVE(&_sysio_pnodes, pno, p_nodes);
- LIST_REMOVE(pno, p_links);
-
- pb = pno->p_base;
- if (!(pb->pb_aliases.lh_first || pb->pb_children.lh_first))
- _sysio_pb_gone(pb);
-
- LIST_INSERT_HEAD(&free_pnodes, pno, p_links);
-}
-
-/*
- * (Re)Validate passed path node.
- */
-int
-_sysio_p_validate(struct pnode *pno, struct intent *intnt, const char *path)
-{
- struct inode *ino;
- struct pnode_base *rootpb;
- int err;
-
- ino = pno->p_base->pb_ino;
- /*
- * An invalid pnode will not have an associated inode. We'll use
- * the FS root inode, then -- It *must* be valid.
- */
- rootpb = pno->p_mount->mnt_root->p_base;
- assert(rootpb->pb_ino);
- err =
- rootpb->pb_ino->i_ops.inop_lookup(pno,
- &ino,
- intnt,
- path);
- /*
- * If the inode lookup returns a different inode, release the old if
- * present and point to the new.
- */
- if (err || pno->p_base->pb_ino != ino) {
- if (pno->p_base->pb_ino)
- I_RELE(pno->p_base->pb_ino);
- pno->p_base->pb_ino = ino;
- }
- return err;
-}
-
-/*
- * Find (or create!) an alias for the given parent and name. A misnomer,
- * really -- This is a "get". Returned path node is referenced.
- */
-int
-_sysio_p_find_alias(struct pnode *parent,
- struct qstr *name,
- struct pnode **pnop)
-{
- struct pnode_base *pb;
- int err;
- struct pnode *pno;
-
- /*
- * Find the named child.
- */
- if (name->len) {
- /*
- * Try the names table.
- */
- pb = names[name->hashval % NAMES_TABLE_LEN].lh_first;
- while (pb) {
- if (pb->pb_parent == parent->p_base &&
- pb->pb_name.len == name->len &&
- strncmp(pb->pb_name.name,
- name->name,
- name->len) == 0)
- break;
- pb = pb->pb_names.le_next;
- }
- } else {
- /*
- * Brute force through the parent's list of children.
- */
- pb = parent->p_base->pb_children.lh_first;
- while (pb) {
- if (pb->pb_parent == parent->p_base &&
- pb->pb_name.len == name->len &&
- strncmp(pb->pb_name.name,
- name->name,
- name->len) == 0)
- break;
- pb = pb->pb_sibs.le_next;
- }
- }
- if (!pb) {
- /*
- * None found, create new child.
- */
- pb = _sysio_pb_new(name, parent->p_base, NULL);
- if (!pb)
- return -ENOMEM;
- }
- /*
- * Now find the proper alias. It's the one with the passed
- * parent.
- */
- err = 0;
- pno = pb->pb_aliases.lh_first;
- while (pno) {
- if (pno->p_parent == parent) {
- P_REF(pno);
- break;
- }
- pno = pno->p_links.le_next;
- }
- if (!pno) {
- /*
- * Hmm. No alias. Just create an invalid one, to be
- * validated later.
- */
- pno = _sysio_p_new_alias(parent, pb, parent->p_mount);
- if (!pno)
- err = -ENOMEM;
- }
- if (!err)
- *pnop = pno;
- return err;
-}
-
-/*
- * Prune idle path base nodes freom the passed sub-tree, including the root.
- */
-static void
-_sysio_prune(struct pnode_base *rpb)
-{
- struct pnode_base *nxtpb, *pb;
-
- nxtpb = rpb->pb_children.lh_first;
- while ((pb = nxtpb)) {
- nxtpb = pb->pb_sibs.le_next;
- if (pb->pb_aliases.lh_first)
- continue;
- if (pb->pb_children.lh_first) {
- _sysio_prune(pb);
- continue;
- }
- _sysio_pb_gone(pb);
- }
- if (rpb->pb_children.lh_first)
- return;
- _sysio_pb_gone(rpb);
-}
-
-/*
- * Prune idle nodes from the passed sub-tree, including the root.
- *
- * Returns the number of aliases on the same mount that could not be pruned.
- * i.e. a zero return means the entire sub-tree is gone.
- */
-size_t
-_sysio_p_prune(struct pnode *root)
-{
- size_t count;
- struct pnode_base *nxtpb, *pb;
- struct pnode *nxtpno, *pno;
-
- count = 0;
- nxtpb = root->p_base->pb_children.lh_first;
- while ((pb = nxtpb)) {
- nxtpb = pb->pb_sibs.le_next;
- nxtpno = pb->pb_aliases.lh_first;
- if (!nxtpno) {
- _sysio_prune(pb);
- continue;
- }
- while ((pno = nxtpno)) {
- nxtpno = pno->p_links.le_next;
- if (pno->p_mount != root->p_mount) {
- /*
- * Not the alias we were looking for.
- */
- continue;
- }
- if (pno->p_base->pb_children.lh_first) {
- /*
- * Node is interior. Recurse.
- */
- count += _sysio_p_prune(pno);
- continue;
- }
- if (pno->p_ref) {
- /*
- * Can't prune; It's active.
- */
- count++;
- continue;
- }
- assert(!pno->p_cover); /* covered => ref'd! */
- assert(!pno->p_base->pb_name.name ||
- pno->p_base->pb_name.hashval);
- /*
- * Ok to prune.
- */
- if (pno->p_mount->mnt_root == pno) {
-#ifndef AUTOMOUNT_FILE_NAME
- count++;
- continue;
-#else
- /*
- * This is an automount-point. Must
- * unmount before relcaim.
- */
- P_REF(pno);
- if (_sysio_do_unmount(pno->p_mount) != 0) {
- P_RELE(pno);
- count++;
- }
- continue;
-#endif
- }
- _sysio_p_gone(pno);
- }
- }
-
- if (count) {
- /*
- * Can't get the root or we disconnect the sub-trees.
- */
- return count + (root->p_ref ? 1 : 0);
- }
-
- /*
- * All that is left is the root. Try for it too.
- */
- if (root->p_ref) {
- count++;
- } else if (root->p_mount->mnt_root == root) {
-#ifndef AUTOMOUNT_FILE_NAME
- count++;
-#else
- /*
- * This is an automount-point. Must
- * unmount before relcaim.
- */
- P_REF(root);
- if (_sysio_do_unmount(root->p_mount) != 0) {
- P_RELE(root);
- count++;
- }
-#endif
- } else
- _sysio_p_gone(root);
-
- return count;
-}
-
-/*
- * Return path tracked by the base path node ancestor chain.
- *
- * Remember, base path nodes track the path relative to the file system and
- * path (alias) nodes track path relative to our name space -- They cross
- * mount points.
- */
-char *
-_sysio_pb_path(struct pnode_base *pb, const char separator)
-{
- char *buf;
- size_t len, n;
- struct pnode_base *tmp;
- char *cp;
-
- /*
- * First pass: Traverse to the root of the sub-tree, remembering
- * lengths.
- */
- len = 0;
- tmp = pb;
- do {
- n = tmp->pb_name.len;
- len += tmp->pb_name.len;
- if (n)
- len++;
- tmp = tmp->pb_parent;
- } while (tmp);
- if (!len)
- len++;
- /*
- * Alloc space.
- */
- buf = malloc(len + 1);
- if (!buf)
- return NULL;
- /*
- * Fill in the path buffer -- Backwards, since we're starting
- * from the end.
- */
- cp = buf;
- *cp = separator;
- cp += len;
- *cp = '\0'; /* NUL term */
- tmp = pb;
- do {
- cp -= tmp->pb_name.len;
- n = tmp->pb_name.len;
- if (n) {
- (void )strncpy(cp, tmp->pb_name.name, n);
- *--cp = separator;
- }
- tmp = tmp->pb_parent;
- } while (tmp);
-
- return buf;
-}
-
-/*
- * Common set attributes routine.
- */
-int
-_sysio_setattr(struct pnode *pno,
- struct inode *ino,
- unsigned mask,
- struct intnl_stat *stbuf)
-{
- /*
- * It is possible that pno is null (for ftruncate call).
- */
-
- if (pno)
- assert(!ino || pno->p_base->pb_ino == ino);
- if (!ino)
- ino = pno->p_base->pb_ino;
- assert(ino);
-
- if (pno && IS_RDONLY(pno))
- return -EROFS;
-
- /*
- * Determining permission to change the attributes is
- * difficult, at best. Just try it.
- */
- return (*ino->i_ops.inop_setattr)(pno, ino, mask, stbuf);
-}
-
-/*
- * Do nothing.
- */
-void
-_sysio_do_noop()
-{
-
- return;
-}
-
-/*
- * Abort.
- */
-void
-_sysio_do_illop()
-{
-
- abort();
-}
-
-/*
- * Return -EBADF
- */
-int
-_sysio_do_ebadf()
-{
-
- return -EBADF;
-}
-
-/*
- * Return -EINVAL
- */
-int
-_sysio_do_einval()
-{
-
- return -EINVAL;
-}
-
-/*
- * Return -ENOENT
- */
-int
-_sysio_do_enoent()
-{
-
- return -ENOENT;
-}
-
-/*
- * Return -ESPIPE
- */
-int
-_sysio_do_espipe()
-{
-
- return -ESPIPE;
-}
-
-/*
- * Return -EISDIR
- */
-int
-_sysio_do_eisdir()
-{
-
- return -EISDIR;
-}
-
-/*
- * Return -ENOSYS
- */
-int
-_sysio_do_enosys()
-{
-
- return -ENOSYS;
-}
-
-
-/*
- * Return -ENODEV
- */
-int
-_sysio_do_enodev()
-{
-
- return -ENODEV;
-}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff