--- /dev/null
+/*
+ * Copyright (c) 2000-2003 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like. Any license provided herein, whether implied or
+ * otherwise, applies only to this software file. Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA 94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+
+
+uint64_t vn_generation; /* vnode generation number */
+spinlock_t vnumber_lock = SPIN_LOCK_UNLOCKED;
+
+/*
+ * Dedicated vnode inactive/reclaim sync semaphores.
+ * Prime number of hash buckets since address is used as the key.
+ */
+#define NVSYNC 37
+#define vptosync(v) (&vsync[((unsigned long)v) % NVSYNC])
+sv_t vsync[NVSYNC];
+
+/*
+ * Translate stat(2) file types to vnode types and vice versa.
+ * Aware of numeric order of S_IFMT and vnode type values.
+ */
+enum vtype iftovt_tab[] = {
+ VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
+ VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON
+};
+
+u_short vttoif_tab[] = {
+ 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFIFO, 0, S_IFSOCK
+};
+
+
+void
+vn_init(void)
+{
+ register sv_t *svp;
+ register int i;
+
+ for (svp = vsync, i = 0; i < NVSYNC; i++, svp++)
+ init_sv(svp, SV_DEFAULT, "vsy", i);
+}
+
+/*
+ * Clean a vnode of filesystem-specific data and prepare it for reuse.
+ */
+STATIC int
+vn_reclaim(
+ struct vnode *vp)
+{
+ int error;
+
+ XFS_STATS_INC(vn_reclaim);
+ vn_trace_entry(vp, "vn_reclaim", (inst_t *)__return_address);
+
+ /*
+ * Only make the VOP_RECLAIM call if there are behaviors
+ * to call.
+ */
+ if (vp->v_fbhv) {
+ VOP_RECLAIM(vp, error);
+ if (error)
+ return -error;
+ }
+ ASSERT(vp->v_fbhv == NULL);
+
+ VN_LOCK(vp);
+ vp->v_flag &= (VRECLM|VWAIT);
+ VN_UNLOCK(vp, 0);
+
+ vp->v_type = VNON;
+ vp->v_fbhv = NULL;
+
+#ifdef XFS_VNODE_TRACE
+ ktrace_free(vp->v_trace);
+ vp->v_trace = NULL;
+#endif
+
+ return 0;
+}
+
+STATIC void
+vn_wakeup(
+ struct vnode *vp)
+{
+ VN_LOCK(vp);
+ if (vp->v_flag & VWAIT)
+ sv_broadcast(vptosync(vp));
+ vp->v_flag &= ~(VRECLM|VWAIT|VMODIFIED);
+ VN_UNLOCK(vp, 0);
+}
+
+int
+vn_wait(
+ struct vnode *vp)
+{
+ VN_LOCK(vp);
+ if (vp->v_flag & (VINACT | VRECLM)) {
+ vp->v_flag |= VWAIT;
+ sv_wait(vptosync(vp), PINOD, &vp->v_lock, 0);
+ return 1;
+ }
+ VN_UNLOCK(vp, 0);
+ return 0;
+}
+
+struct vnode *
+vn_initialize(
+ struct inode *inode)
+{
+ struct vnode *vp = LINVFS_GET_VP(inode);
+
+ XFS_STATS_INC(vn_active);
+ XFS_STATS_INC(vn_alloc);
+
+ vp->v_flag = VMODIFIED;
+ spinlock_init(&vp->v_lock, "v_lock");
+
+ spin_lock(&vnumber_lock);
+ if (!++vn_generation) /* v_number shouldn't be zero */
+ vn_generation++;
+ vp->v_number = vn_generation;
+ spin_unlock(&vnumber_lock);
+
+ ASSERT(VN_CACHED(vp) == 0);
+
+ /* Initialize the first behavior and the behavior chain head. */
+ vn_bhv_head_init(VN_BHV_HEAD(vp), "vnode");
+
+#ifdef XFS_VNODE_TRACE
+ vp->v_trace = ktrace_alloc(VNODE_TRACE_SIZE, KM_SLEEP);
+ printk("Allocated VNODE_TRACE at 0x%p\n", vp->v_trace);
+#endif /* XFS_VNODE_TRACE */
+
+ vn_trace_exit(vp, "vn_initialize", (inst_t *)__return_address);
+ return vp;
+}
+
+/*
+ * Get a reference on a vnode.
+ */
+vnode_t *
+vn_get(
+ struct vnode *vp,
+ vmap_t *vmap)
+{
+ struct inode *inode;
+
+ XFS_STATS_INC(vn_get);
+ inode = LINVFS_GET_IP(vp);
+ if (inode->i_state & I_FREEING)
+ return NULL;
+
+ inode = ilookup(vmap->v_vfsp->vfs_super, vmap->v_ino);
+ if (!inode) /* Inode not present */
+ return NULL;
+
+ vn_trace_exit(vp, "vn_get", (inst_t *)__return_address);
+
+ return vp;
+}
+
+/*
+ * Revalidate the Linux inode from the vnode.
+ */
+int
+vn_revalidate(
+ struct vnode *vp)
+{
+ struct inode *inode;
+ vattr_t va;
+ int error;
+
+ vn_trace_entry(vp, "vn_revalidate", (inst_t *)__return_address);
+ ASSERT(vp->v_fbhv != NULL);
+
+ va.va_mask = XFS_AT_STAT|XFS_AT_XFLAGS;
+ VOP_GETATTR(vp, &va, 0, NULL, error);
+ if (!error) {
+ inode = LINVFS_GET_IP(vp);
+ inode->i_mode = VTTOIF(va.va_type) | va.va_mode;
+ inode->i_nlink = va.va_nlink;
+ inode->i_uid = va.va_uid;
+ inode->i_gid = va.va_gid;
+ inode->i_blocks = va.va_nblocks;
+ inode->i_mtime = va.va_mtime;
+ inode->i_ctime = va.va_ctime;
+ inode->i_atime = va.va_atime;
+ if (va.va_xflags & XFS_XFLAG_IMMUTABLE)
+ inode->i_flags |= S_IMMUTABLE;
+ else
+ inode->i_flags &= ~S_IMMUTABLE;
+ if (va.va_xflags & XFS_XFLAG_APPEND)
+ inode->i_flags |= S_APPEND;
+ else
+ inode->i_flags &= ~S_APPEND;
+ if (va.va_xflags & XFS_XFLAG_SYNC)
+ inode->i_flags |= S_SYNC;
+ else
+ inode->i_flags &= ~S_SYNC;
+ if (va.va_xflags & XFS_XFLAG_NOATIME)
+ inode->i_flags |= S_NOATIME;
+ else
+ inode->i_flags &= ~S_NOATIME;
+ VUNMODIFY(vp);
+ }
+ return -error;
+}
+
+/*
+ * purge a vnode from the cache
+ * At this point the vnode is guaranteed to have no references (vn_count == 0)
+ * The caller has to make sure that there are no ways someone could
+ * get a handle (via vn_get) on the vnode (usually done via a mount/vfs lock).
+ */
+void
+vn_purge(
+ struct vnode *vp,
+ vmap_t *vmap)
+{
+ vn_trace_entry(vp, "vn_purge", (inst_t *)__return_address);
+
+again:
+ /*
+ * Check whether vp has already been reclaimed since our caller
+ * sampled its version while holding a filesystem cache lock that
+ * its VOP_RECLAIM function acquires.
+ */
+ VN_LOCK(vp);
+ if (vp->v_number != vmap->v_number) {
+ VN_UNLOCK(vp, 0);
+ return;
+ }
+
+ /*
+ * If vp is being reclaimed or inactivated, wait until it is inert,
+ * then proceed. Can't assume that vnode is actually reclaimed
+ * just because the reclaimed flag is asserted -- a vn_alloc
+ * reclaim can fail.
+ */
+ if (vp->v_flag & (VINACT | VRECLM)) {
+ ASSERT(vn_count(vp) == 0);
+ vp->v_flag |= VWAIT;
+ sv_wait(vptosync(vp), PINOD, &vp->v_lock, 0);
+ goto again;
+ }
+
+ /*
+ * Another process could have raced in and gotten this vnode...
+ */
+ if (vn_count(vp) > 0) {
+ VN_UNLOCK(vp, 0);
+ return;
+ }
+
+ XFS_STATS_DEC(vn_active);
+ vp->v_flag |= VRECLM;
+ VN_UNLOCK(vp, 0);
+
+ /*
+ * Call VOP_RECLAIM and clean vp. The FSYNC_INVAL flag tells
+ * vp's filesystem to flush and invalidate all cached resources.
+ * When vn_reclaim returns, vp should have no private data,
+ * either in a system cache or attached to v_data.
+ */
+ if (vn_reclaim(vp) != 0)
+ panic("vn_purge: cannot reclaim");
+
+ /*
+ * Wakeup anyone waiting for vp to be reclaimed.
+ */
+ vn_wakeup(vp);
+}
+
+/*
+ * Add a reference to a referenced vnode.
+ */
+struct vnode *
+vn_hold(
+ struct vnode *vp)
+{
+ struct inode *inode;
+
+ XFS_STATS_INC(vn_hold);
+
+ VN_LOCK(vp);
+ inode = igrab(LINVFS_GET_IP(vp));
+ ASSERT(inode);
+ VN_UNLOCK(vp, 0);
+
+ return vp;
+}
+
+/*
+ * Call VOP_INACTIVE on last reference.
+ */
+void
+vn_rele(
+ struct vnode *vp)
+{
+ int vcnt;
+ int cache;
+
+ XFS_STATS_INC(vn_rele);
+
+ VN_LOCK(vp);
+
+ vn_trace_entry(vp, "vn_rele", (inst_t *)__return_address);
+ vcnt = vn_count(vp);
+
+ /*
+ * Since we always get called from put_inode we know
+ * that i_count won't be decremented after we
+ * return.
+ */
+ if (!vcnt) {
+ /*
+ * As soon as we turn this on, noone can find us in vn_get
+ * until we turn off VINACT or VRECLM
+ */
+ vp->v_flag |= VINACT;
+ VN_UNLOCK(vp, 0);
+
+ /*
+ * Do not make the VOP_INACTIVE call if there
+ * are no behaviors attached to the vnode to call.
+ */
+ if (vp->v_fbhv)
+ VOP_INACTIVE(vp, NULL, cache);
+
+ VN_LOCK(vp);
+ if (vp->v_flag & VWAIT)
+ sv_broadcast(vptosync(vp));
+
+ vp->v_flag &= ~(VINACT|VWAIT|VRECLM|VMODIFIED);
+ }
+
+ VN_UNLOCK(vp, 0);
+
+ vn_trace_exit(vp, "vn_rele", (inst_t *)__return_address);
+}
+
+/*
+ * Finish the removal of a vnode.
+ */
+void
+vn_remove(
+ struct vnode *vp)
+{
+ vmap_t vmap;
+
+ /* Make sure we don't do this to the same vnode twice */
+ if (!(vp->v_fbhv))
+ return;
+
+ XFS_STATS_INC(vn_remove);
+ vn_trace_exit(vp, "vn_remove", (inst_t *)__return_address);
+
+ /*
+ * After the following purge the vnode
+ * will no longer exist.
+ */
+ VMAP(vp, vmap);
+ vn_purge(vp, &vmap);
+}
+
+
+#ifdef XFS_VNODE_TRACE
+
+#define KTRACE_ENTER(vp, vk, s, line, ra) \
+ ktrace_enter( (vp)->v_trace, \
+/* 0 */ (void *)(__psint_t)(vk), \
+/* 1 */ (void *)(s), \
+/* 2 */ (void *)(__psint_t) line, \
+/* 3 */ (void *)(vn_count(vp)), \
+/* 4 */ (void *)(ra), \
+/* 5 */ (void *)(__psunsigned_t)(vp)->v_flag, \
+/* 6 */ (void *)(__psint_t)smp_processor_id(), \
+/* 7 */ (void *)(__psint_t)(current->pid), \
+/* 8 */ (void *)__return_address, \
+/* 9 */ 0, 0, 0, 0, 0, 0, 0)
+
+/*
+ * Vnode tracing code.
+ */
+void
+vn_trace_entry(vnode_t *vp, char *func, inst_t *ra)
+{
+ KTRACE_ENTER(vp, VNODE_KTRACE_ENTRY, func, 0, ra);
+}
+
+void
+vn_trace_exit(vnode_t *vp, char *func, inst_t *ra)
+{
+ KTRACE_ENTER(vp, VNODE_KTRACE_EXIT, func, 0, ra);
+}
+
+void
+vn_trace_hold(vnode_t *vp, char *file, int line, inst_t *ra)
+{
+ KTRACE_ENTER(vp, VNODE_KTRACE_HOLD, file, line, ra);
+}
+
+void
+vn_trace_ref(vnode_t *vp, char *file, int line, inst_t *ra)
+{
+ KTRACE_ENTER(vp, VNODE_KTRACE_REF, file, line, ra);
+}
+
+void
+vn_trace_rele(vnode_t *vp, char *file, int line, inst_t *ra)
+{
+ KTRACE_ENTER(vp, VNODE_KTRACE_RELE, file, line, ra);
+}
+#endif /* XFS_VNODE_TRACE */
git://git.onelab.eu / linux-2.6.git / blobdiff