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Subject[PATCH 08/16] GFS2: Resource group code
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[PATCH 08/16] GFS2: Resource group code

GFS2's resource group handling code and code for manipulating bitmaps.


Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>


fs/gfs2/bits.c | 182 +++++++
fs/gfs2/bits.h | 28 +
fs/gfs2/rgrp.c | 1369 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/gfs2/rgrp.h | 62 ++
4 files changed, 1641 insertions(+)

--- /dev/null
+++ b/fs/gfs2/rgrp.c
@@ -0,0 +1,1369 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/fs.h>
+#include <linux/gfs2_ondisk.h>
+#include <asm/semaphore.h>
+
+#include "gfs2.h"
+#include "lm_interface.h"
+#include "incore.h"
+#include "bits.h"
+#include "glock.h"
+#include "glops.h"
+#include "lops.h"
+#include "meta_io.h"
+#include "quota.h"
+#include "rgrp.h"
+#include "super.h"
+#include "trans.h"
+#include "ops_file.h"
+#include "util.h"
+
+/**
+ * gfs2_rgrp_verify - Verify that a resource group is consistent
+ * @sdp: the filesystem
+ * @rgd: the rgrp
+ *
+ */
+
+void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ struct gfs2_bitmap *bi = NULL;
+ uint32_t length = rgd->rd_ri.ri_length;
+ uint32_t count[4], tmp;
+ int buf, x;
+
+ memset(count, 0, 4 * sizeof(uint32_t));
+
+ /* Count # blocks in each of 4 possible allocation states */
+ for (buf = 0; buf < length; buf++) {
+ bi = rgd->rd_bits + buf;
+ for (x = 0; x < 4; x++)
+ count[x] += gfs2_bitcount(rgd,
+ bi->bi_bh->b_data +
+ bi->bi_offset,
+ bi->bi_len, x);
+ }
+
+ if (count[0] != rgd->rd_rg.rg_free) {
+ if (gfs2_consist_rgrpd(rgd))
+ fs_err(sdp, "free data mismatch: %u != %u\n",
+ count[0], rgd->rd_rg.rg_free);
+ return;
+ }
+
+ tmp = rgd->rd_ri.ri_data -
+ rgd->rd_rg.rg_free -
+ rgd->rd_rg.rg_dinodes;
+ if (count[1] != tmp) {
+ if (gfs2_consist_rgrpd(rgd))
+ fs_err(sdp, "used data mismatch: %u != %u\n",
+ count[1], tmp);
+ return;
+ }
+
+ if (count[2]) {
+ if (gfs2_consist_rgrpd(rgd))
+ fs_err(sdp, "free metadata mismatch: %u != 0\n",
+ count[2]);
+ return;
+ }
+
+ if (count[3] != rgd->rd_rg.rg_dinodes) {
+ if (gfs2_consist_rgrpd(rgd))
+ fs_err(sdp, "used metadata mismatch: %u != %u\n",
+ count[3], rgd->rd_rg.rg_dinodes);
+ return;
+ }
+}
+
+static inline int rgrp_contains_block(struct gfs2_rindex *ri, uint64_t block)
+{
+ uint64_t first = ri->ri_data0;
+ uint64_t last = first + ri->ri_data;
+ return !!(first <= block && block < last);
+}
+
+/**
+ * gfs2_blk2rgrpd - Find resource group for a given data/meta block number
+ * @sdp: The GFS2 superblock
+ * @n: The data block number
+ *
+ * Returns: The resource group, or NULL if not found
+ */
+
+struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, uint64_t blk)
+{
+ struct gfs2_rgrpd *rgd;
+
+ spin_lock(&sdp->sd_rindex_spin);
+
+ list_for_each_entry(rgd, &sdp->sd_rindex_mru_list, rd_list_mru) {
+ if (rgrp_contains_block(&rgd->rd_ri, blk)) {
+ list_move(&rgd->rd_list_mru, &sdp->sd_rindex_mru_list);
+ spin_unlock(&sdp->sd_rindex_spin);
+ return rgd;
+ }
+ }
+
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return NULL;
+}
+
+/**
+ * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
+ * @sdp: The GFS2 superblock
+ *
+ * Returns: The first rgrp in the filesystem
+ */
+
+struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
+{
+ gfs2_assert(sdp, !list_empty(&sdp->sd_rindex_list));
+ return list_entry(sdp->sd_rindex_list.next, struct gfs2_rgrpd, rd_list);
+}
+
+/**
+ * gfs2_rgrpd_get_next - get the next RG
+ * @rgd: A RG
+ *
+ * Returns: The next rgrp
+ */
+
+struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
+{
+ if (rgd->rd_list.next == &rgd->rd_sbd->sd_rindex_list)
+ return NULL;
+ return list_entry(rgd->rd_list.next, struct gfs2_rgrpd, rd_list);
+}
+
+static void clear_rgrpdi(struct gfs2_sbd *sdp)
+{
+ struct list_head *head;
+ struct gfs2_rgrpd *rgd;
+ struct gfs2_glock *gl;
+
+ spin_lock(&sdp->sd_rindex_spin);
+ sdp->sd_rindex_forward = NULL;
+ head = &sdp->sd_rindex_recent_list;
+ while (!list_empty(head)) {
+ rgd = list_entry(head->next, struct gfs2_rgrpd, rd_recent);
+ list_del(&rgd->rd_recent);
+ }
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ head = &sdp->sd_rindex_list;
+ while (!list_empty(head)) {
+ rgd = list_entry(head->next, struct gfs2_rgrpd, rd_list);
+ gl = rgd->rd_gl;
+
+ list_del(&rgd->rd_list);
+ list_del(&rgd->rd_list_mru);
+
+ if (gl) {
+ gl->gl_object = NULL;
+ gfs2_glock_put(gl);
+ }
+
+ kfree(rgd->rd_bits);
+ kfree(rgd);
+ }
+}
+
+void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
+{
+ mutex_lock(&sdp->sd_rindex_mutex);
+ clear_rgrpdi(sdp);
+ mutex_unlock(&sdp->sd_rindex_mutex);
+}
+
+/**
+ * gfs2_compute_bitstructs - Compute the bitmap sizes
+ * @rgd: The resource group descriptor
+ *
+ * Calculates bitmap descriptors, one for each block that contains bitmap data
+ *
+ * Returns: errno
+ */
+
+static int compute_bitstructs(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ struct gfs2_bitmap *bi;
+ uint32_t length = rgd->rd_ri.ri_length; /* # blocks in hdr & bitmap */
+ uint32_t bytes_left, bytes;
+ int x;
+
+ rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_KERNEL);
+ if (!rgd->rd_bits)
+ return -ENOMEM;
+
+ bytes_left = rgd->rd_ri.ri_bitbytes;
+
+ for (x = 0; x < length; x++) {
+ bi = rgd->rd_bits + x;
+
+ /* small rgrp; bitmap stored completely in header block */
+ if (length == 1) {
+ bytes = bytes_left;
+ bi->bi_offset = sizeof(struct gfs2_rgrp);
+ bi->bi_start = 0;
+ bi->bi_len = bytes;
+ /* header block */
+ } else if (x == 0) {
+ bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
+ bi->bi_offset = sizeof(struct gfs2_rgrp);
+ bi->bi_start = 0;
+ bi->bi_len = bytes;
+ /* last block */
+ } else if (x + 1 == length) {
+ bytes = bytes_left;
+ bi->bi_offset = sizeof(struct gfs2_meta_header);
+ bi->bi_start = rgd->rd_ri.ri_bitbytes - bytes_left;
+ bi->bi_len = bytes;
+ /* other blocks */
+ } else {
+ bytes = sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_meta_header);
+ bi->bi_offset = sizeof(struct gfs2_meta_header);
+ bi->bi_start = rgd->rd_ri.ri_bitbytes - bytes_left;
+ bi->bi_len = bytes;
+ }
+
+ bytes_left -= bytes;
+ }
+
+ if (bytes_left) {
+ gfs2_consist_rgrpd(rgd);
+ return -EIO;
+ }
+ bi = rgd->rd_bits + (length - 1);
+ if ((bi->bi_start + bi->bi_len) * GFS2_NBBY != rgd->rd_ri.ri_data) {
+ if (gfs2_consist_rgrpd(rgd)) {
+ gfs2_rindex_print(&rgd->rd_ri);
+ fs_err(sdp, "start=%u len=%u offset=%u\n",
+ bi->bi_start, bi->bi_len, bi->bi_offset);
+ }
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * gfs2_ri_update - Pull in a new resource index from the disk
+ * @gl: The glock covering the rindex inode
+ *
+ * Returns: 0 on successful update, error code otherwise
+ */
+
+static int gfs2_ri_update(struct gfs2_inode *ip)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct inode *inode = ip->i_vnode;
+ struct gfs2_rgrpd *rgd;
+ char buf[sizeof(struct gfs2_rindex)];
+ struct file_ra_state ra_state;
+ uint64_t junk = ip->i_di.di_size;
+ int error;
+
+ if (do_div(junk, sizeof(struct gfs2_rindex))) {
+ gfs2_consist_inode(ip);
+ return -EIO;
+ }
+
+ clear_rgrpdi(sdp);
+
+ file_ra_state_init(&ra_state, inode->i_mapping);
+ for (sdp->sd_rgrps = 0;; sdp->sd_rgrps++) {
+ loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
+ error = gfs2_internal_read(ip, &ra_state, buf, &pos,
+ sizeof(struct gfs2_rindex));
+ if (!error)
+ break;
+ if (error != sizeof(struct gfs2_rindex)) {
+ if (error > 0)
+ error = -EIO;
+ goto fail;
+ }
+
+ rgd = kzalloc(sizeof(struct gfs2_rgrpd), GFP_KERNEL);
+ error = -ENOMEM;
+ if (!rgd)
+ goto fail;
+
+ mutex_init(&rgd->rd_mutex);
+ lops_init_le(&rgd->rd_le, &gfs2_rg_lops);
+ rgd->rd_sbd = sdp;
+
+ list_add_tail(&rgd->rd_list, &sdp->sd_rindex_list);
+ list_add_tail(&rgd->rd_list_mru, &sdp->sd_rindex_mru_list);
+
+ gfs2_rindex_in(&rgd->rd_ri, buf);
+
+ error = compute_bitstructs(rgd);
+ if (error)
+ goto fail;
+
+ error = gfs2_glock_get(sdp, rgd->rd_ri.ri_addr,
+ &gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
+ if (error)
+ goto fail;
+
+ rgd->rd_gl->gl_object = rgd;
+ rgd->rd_rg_vn = rgd->rd_gl->gl_vn - 1;
+ }
+
+ sdp->sd_rindex_vn = ip->i_gl->gl_vn;
+
+ return 0;
+
+ fail:
+ clear_rgrpdi(sdp);
+
+ return error;
+}
+
+/**
+ * gfs2_rindex_hold - Grab a lock on the rindex
+ * @sdp: The GFS2 superblock
+ * @ri_gh: the glock holder
+ *
+ * We grab a lock on the rindex inode to make sure that it doesn't
+ * change whilst we are performing an operation. We keep this lock
+ * for quite long periods of time compared to other locks. This
+ * doesn't matter, since it is shared and it is very, very rarely
+ * accessed in the exclusive mode (i.e. only when expanding the filesystem).
+ *
+ * This makes sure that we're using the latest copy of the resource index
+ * special file, which might have been updated if someone expanded the
+ * filesystem (via gfs2_grow utility), which adds new resource groups.
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+
+int gfs2_rindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ri_gh)
+{
+ struct gfs2_inode *ip = sdp->sd_rindex->u.generic_ip;
+ struct gfs2_glock *gl = ip->i_gl;
+ int error;
+
+ error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, ri_gh);
+ if (error)
+ return error;
+
+ /* Read new copy from disk if we don't have the latest */
+ if (sdp->sd_rindex_vn != gl->gl_vn) {
+ mutex_lock(&sdp->sd_rindex_mutex);
+ if (sdp->sd_rindex_vn != gl->gl_vn) {
+ error = gfs2_ri_update(ip);
+ if (error)
+ gfs2_glock_dq_uninit(ri_gh);
+ }
+ mutex_unlock(&sdp->sd_rindex_mutex);
+ }
+
+ return error;
+}
+
+/**
+ * gfs2_rgrp_bh_get - Read in a RG's header and bitmaps
+ * @rgd: the struct gfs2_rgrpd describing the RG to read in
+ *
+ * Read in all of a Resource Group's header and bitmap blocks.
+ * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps.
+ *
+ * Returns: errno
+ */
+
+int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ struct gfs2_glock *gl = rgd->rd_gl;
+ unsigned int length = rgd->rd_ri.ri_length;
+ struct gfs2_bitmap *bi;
+ unsigned int x, y;
+ int error;
+
+ mutex_lock(&rgd->rd_mutex);
+
+ spin_lock(&sdp->sd_rindex_spin);
+ if (rgd->rd_bh_count) {
+ rgd->rd_bh_count++;
+ spin_unlock(&sdp->sd_rindex_spin);
+ mutex_unlock(&rgd->rd_mutex);
+ return 0;
+ }
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ for (x = 0; x < length; x++) {
+ bi = rgd->rd_bits + x;
+ error = gfs2_meta_read(gl, rgd->rd_ri.ri_addr + x, DIO_START,
+ &bi->bi_bh);
+ if (error)
+ goto fail;
+ }
+
+ for (y = length; y--;) {
+ bi = rgd->rd_bits + y;
+ error = gfs2_meta_reread(sdp, bi->bi_bh, DIO_WAIT);
+ if (error)
+ goto fail;
+ if (gfs2_metatype_check(sdp, bi->bi_bh,
+ (y) ? GFS2_METATYPE_RB :
+ GFS2_METATYPE_RG)) {
+ error = -EIO;
+ goto fail;
+ }
+ }
+
+ if (rgd->rd_rg_vn != gl->gl_vn) {
+ gfs2_rgrp_in(&rgd->rd_rg, (rgd->rd_bits[0].bi_bh)->b_data);
+ rgd->rd_rg_vn = gl->gl_vn;
+ }
+
+ spin_lock(&sdp->sd_rindex_spin);
+ rgd->rd_free_clone = rgd->rd_rg.rg_free;
+ rgd->rd_bh_count++;
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ mutex_unlock(&rgd->rd_mutex);
+
+ return 0;
+
+ fail:
+ while (x--) {
+ bi = rgd->rd_bits + x;
+ brelse(bi->bi_bh);
+ bi->bi_bh = NULL;
+ gfs2_assert_warn(sdp, !bi->bi_clone);
+ }
+ mutex_unlock(&rgd->rd_mutex);
+
+ return error;
+}
+
+void gfs2_rgrp_bh_hold(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+
+ spin_lock(&sdp->sd_rindex_spin);
+ gfs2_assert_warn(rgd->rd_sbd, rgd->rd_bh_count);
+ rgd->rd_bh_count++;
+ spin_unlock(&sdp->sd_rindex_spin);
+}
+
+/**
+ * gfs2_rgrp_bh_put - Release RG bitmaps read in with gfs2_rgrp_bh_get()
+ * @rgd: the struct gfs2_rgrpd describing the RG to read in
+ *
+ */
+
+void gfs2_rgrp_bh_put(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ int x, length = rgd->rd_ri.ri_length;
+
+ spin_lock(&sdp->sd_rindex_spin);
+ gfs2_assert_warn(rgd->rd_sbd, rgd->rd_bh_count);
+ if (--rgd->rd_bh_count) {
+ spin_unlock(&sdp->sd_rindex_spin);
+ return;
+ }
+
+ for (x = 0; x < length; x++) {
+ struct gfs2_bitmap *bi = rgd->rd_bits + x;
+ kfree(bi->bi_clone);
+ bi->bi_clone = NULL;
+ brelse(bi->bi_bh);
+ bi->bi_bh = NULL;
+ }
+
+ spin_unlock(&sdp->sd_rindex_spin);
+}
+
+void gfs2_rgrp_repolish_clones(struct gfs2_rgrpd *rgd)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ unsigned int length = rgd->rd_ri.ri_length;
+ unsigned int x;
+
+ for (x = 0; x < length; x++) {
+ struct gfs2_bitmap *bi = rgd->rd_bits + x;
+ if (!bi->bi_clone)
+ continue;
+ memcpy(bi->bi_clone + bi->bi_offset,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len);
+ }
+
+ spin_lock(&sdp->sd_rindex_spin);
+ rgd->rd_free_clone = rgd->rd_rg.rg_free;
+ spin_unlock(&sdp->sd_rindex_spin);
+}
+
+/**
+ * gfs2_alloc_get - get the struct gfs2_alloc structure for an inode
+ * @ip: the incore GFS2 inode structure
+ *
+ * Returns: the struct gfs2_alloc
+ */
+
+struct gfs2_alloc *gfs2_alloc_get(struct gfs2_inode *ip)
+{
+ struct gfs2_alloc *al = &ip->i_alloc;
+
+ /* FIXME: Should assert that the correct locks are held here... */
+ memset(al, 0, sizeof(*al));
+ return al;
+}
+
+/**
+ * gfs2_alloc_put - throw away the struct gfs2_alloc for an inode
+ * @ip: the inode
+ *
+ */
+
+void gfs2_alloc_put(struct gfs2_inode *ip)
+{
+ return;
+}
+
+/**
+ * try_rgrp_fit - See if a given reservation will fit in a given RG
+ * @rgd: the RG data
+ * @al: the struct gfs2_alloc structure describing the reservation
+ *
+ * If there's room for the requested blocks to be allocated from the RG:
+ * Sets the $al_reserved_data field in @al.
+ * Sets the $al_reserved_meta field in @al.
+ * Sets the $al_rgd field in @al.
+ *
+ * Returns: 1 on success (it fits), 0 on failure (it doesn't fit)
+ */
+
+static int try_rgrp_fit(struct gfs2_rgrpd *rgd, struct gfs2_alloc *al)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ int ret = 0;
+
+ spin_lock(&sdp->sd_rindex_spin);
+ if (rgd->rd_free_clone >= al->al_requested) {
+ al->al_rgd = rgd;
+ ret = 1;
+ }
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return ret;
+}
+
+/**
+ * recent_rgrp_first - get first RG from "recent" list
+ * @sdp: The GFS2 superblock
+ * @rglast: address of the rgrp used last
+ *
+ * Returns: The first rgrp in the recent list
+ */
+
+static struct gfs2_rgrpd *recent_rgrp_first(struct gfs2_sbd *sdp,
+ uint64_t rglast)
+{
+ struct gfs2_rgrpd *rgd = NULL;
+
+ spin_lock(&sdp->sd_rindex_spin);
+
+ if (list_empty(&sdp->sd_rindex_recent_list))
+ goto out;
+
+ if (!rglast)
+ goto first;
+
+ list_for_each_entry(rgd, &sdp->sd_rindex_recent_list, rd_recent) {
+ if (rgd->rd_ri.ri_addr == rglast)
+ goto out;
+ }
+
+ first:
+ rgd = list_entry(sdp->sd_rindex_recent_list.next, struct gfs2_rgrpd,
+ rd_recent);
+
+ out:
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return rgd;
+}
+
+/**
+ * recent_rgrp_next - get next RG from "recent" list
+ * @cur_rgd: current rgrp
+ * @remove:
+ *
+ * Returns: The next rgrp in the recent list
+ */
+
+static struct gfs2_rgrpd *recent_rgrp_next(struct gfs2_rgrpd *cur_rgd,
+ int remove)
+{
+ struct gfs2_sbd *sdp = cur_rgd->rd_sbd;
+ struct list_head *head;
+ struct gfs2_rgrpd *rgd;
+
+ spin_lock(&sdp->sd_rindex_spin);
+
+ head = &sdp->sd_rindex_recent_list;
+
+ list_for_each_entry(rgd, head, rd_recent) {
+ if (rgd == cur_rgd) {
+ if (cur_rgd->rd_recent.next != head)
+ rgd = list_entry(cur_rgd->rd_recent.next,
+ struct gfs2_rgrpd, rd_recent);
+ else
+ rgd = NULL;
+
+ if (remove)
+ list_del(&cur_rgd->rd_recent);
+
+ goto out;
+ }
+ }
+
+ rgd = NULL;
+ if (!list_empty(head))
+ rgd = list_entry(head->next, struct gfs2_rgrpd, rd_recent);
+
+ out:
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return rgd;
+}
+
+/**
+ * recent_rgrp_add - add an RG to tail of "recent" list
+ * @new_rgd: The rgrp to add
+ *
+ */
+
+static void recent_rgrp_add(struct gfs2_rgrpd *new_rgd)
+{
+ struct gfs2_sbd *sdp = new_rgd->rd_sbd;
+ struct gfs2_rgrpd *rgd;
+ unsigned int count = 0;
+ unsigned int max = sdp->sd_rgrps / gfs2_jindex_size(sdp);
+
+ spin_lock(&sdp->sd_rindex_spin);
+
+ list_for_each_entry(rgd, &sdp->sd_rindex_recent_list, rd_recent) {
+ if (rgd == new_rgd)
+ goto out;
+
+ if (++count >= max)
+ goto out;
+ }
+ list_add_tail(&new_rgd->rd_recent, &sdp->sd_rindex_recent_list);
+
+ out:
+ spin_unlock(&sdp->sd_rindex_spin);
+}
+
+/**
+ * forward_rgrp_get - get an rgrp to try next from full list
+ * @sdp: The GFS2 superblock
+ *
+ * Returns: The rgrp to try next
+ */
+
+static struct gfs2_rgrpd *forward_rgrp_get(struct gfs2_sbd *sdp)
+{
+ struct gfs2_rgrpd *rgd;
+ unsigned int journals = gfs2_jindex_size(sdp);
+ unsigned int rg = 0, x;
+
+ spin_lock(&sdp->sd_rindex_spin);
+
+ rgd = sdp->sd_rindex_forward;
+ if (!rgd) {
+ if (sdp->sd_rgrps >= journals)
+ rg = sdp->sd_rgrps * sdp->sd_jdesc->jd_jid / journals;
+
+ for (x = 0, rgd = gfs2_rgrpd_get_first(sdp);
+ x < rg;
+ x++, rgd = gfs2_rgrpd_get_next(rgd))
+ /* Do Nothing */;
+
+ sdp->sd_rindex_forward = rgd;
+ }
+
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return rgd;
+}
+
+/**
+ * forward_rgrp_set - set the forward rgrp pointer
+ * @sdp: the filesystem
+ * @rgd: The new forward rgrp
+ *
+ */
+
+static void forward_rgrp_set(struct gfs2_sbd *sdp, struct gfs2_rgrpd *rgd)
+{
+ spin_lock(&sdp->sd_rindex_spin);
+ sdp->sd_rindex_forward = rgd;
+ spin_unlock(&sdp->sd_rindex_spin);
+}
+
+/**
+ * get_local_rgrp - Choose and lock a rgrp for allocation
+ * @ip: the inode to reserve space for
+ * @rgp: the chosen and locked rgrp
+ *
+ * Try to acquire rgrp in way which avoids contending with others.
+ *
+ * Returns: errno
+ */
+
+static int get_local_rgrp(struct gfs2_inode *ip)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_rgrpd *rgd, *begin = NULL;
+ struct gfs2_alloc *al = &ip->i_alloc;
+ int flags = LM_FLAG_TRY;
+ int skipped = 0;
+ int loops = 0;
+ int error;
+
+ /* Try recently successful rgrps */
+
+ rgd = recent_rgrp_first(sdp, ip->i_last_rg_alloc);
+
+ while (rgd) {
+ error = gfs2_glock_nq_init(rgd->rd_gl,
+ LM_ST_EXCLUSIVE, LM_FLAG_TRY,
+ &al->al_rgd_gh);
+ switch (error) {
+ case 0:
+ if (try_rgrp_fit(rgd, al))
+ goto out;
+ gfs2_glock_dq_uninit(&al->al_rgd_gh);
+ rgd = recent_rgrp_next(rgd, 1);
+ break;
+
+ case GLR_TRYFAILED:
+ rgd = recent_rgrp_next(rgd, 0);
+ break;
+
+ default:
+ return error;
+ }
+ }
+
+ /* Go through full list of rgrps */
+
+ begin = rgd = forward_rgrp_get(sdp);
+
+ for (;;) {
+ error = gfs2_glock_nq_init(rgd->rd_gl,
+ LM_ST_EXCLUSIVE, flags,
+ &al->al_rgd_gh);
+ switch (error) {
+ case 0:
+ if (try_rgrp_fit(rgd, al))
+ goto out;
+ gfs2_glock_dq_uninit(&al->al_rgd_gh);
+ break;
+
+ case GLR_TRYFAILED:
+ skipped++;
+ break;
+
+ default:
+ return error;
+ }
+
+ rgd = gfs2_rgrpd_get_next(rgd);
+ if (!rgd)
+ rgd = gfs2_rgrpd_get_first(sdp);
+
+ if (rgd == begin) {
+ if (++loops >= 2 || !skipped)
+ return -ENOSPC;
+ flags = 0;
+ }
+ }
+
+ out:
+ ip->i_last_rg_alloc = rgd->rd_ri.ri_addr;
+
+ if (begin) {
+ recent_rgrp_add(rgd);
+ rgd = gfs2_rgrpd_get_next(rgd);
+ if (!rgd)
+ rgd = gfs2_rgrpd_get_first(sdp);
+ forward_rgrp_set(sdp, rgd);
+ }
+
+ return 0;
+}
+
+/**
+ * gfs2_inplace_reserve_i - Reserve space in the filesystem
+ * @ip: the inode to reserve space for
+ *
+ * Returns: errno
+ */
+
+int gfs2_inplace_reserve_i(struct gfs2_inode *ip, char *file, unsigned int line)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_alloc *al = &ip->i_alloc;
+ int error;
+
+ if (gfs2_assert_warn(sdp, al->al_requested))
+ return -EINVAL;
+
+ error = gfs2_rindex_hold(sdp, &al->al_ri_gh);
+ if (error)
+ return error;
+
+ error = get_local_rgrp(ip);
+ if (error) {
+ gfs2_glock_dq_uninit(&al->al_ri_gh);
+ return error;
+ }
+
+ al->al_file = file;
+ al->al_line = line;
+
+ return 0;
+}
+
+/**
+ * gfs2_inplace_release - release an inplace reservation
+ * @ip: the inode the reservation was taken out on
+ *
+ * Release a reservation made by gfs2_inplace_reserve().
+ */
+
+void gfs2_inplace_release(struct gfs2_inode *ip)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_alloc *al = &ip->i_alloc;
+
+ if (gfs2_assert_warn(sdp, al->al_alloced <= al->al_requested) == -1)
+ fs_warn(sdp, "al_alloced = %u, al_requested = %u "
+ "al_file = %s, al_line = %u\n",
+ al->al_alloced, al->al_requested, al->al_file,
+ al->al_line);
+
+ al->al_rgd = NULL;
+ gfs2_glock_dq_uninit(&al->al_rgd_gh);
+ gfs2_glock_dq_uninit(&al->al_ri_gh);
+}
+
+/**
+ * gfs2_get_block_type - Check a block in a RG is of given type
+ * @rgd: the resource group holding the block
+ * @block: the block number
+ *
+ * Returns: The block type (GFS2_BLKST_*)
+ */
+
+unsigned char gfs2_get_block_type(struct gfs2_rgrpd *rgd, uint64_t block)
+{
+ struct gfs2_bitmap *bi = NULL;
+ uint32_t length, rgrp_block, buf_block;
+ unsigned int buf;
+ unsigned char type;
+
+ length = rgd->rd_ri.ri_length;
+ rgrp_block = block - rgd->rd_ri.ri_data0;
+
+ for (buf = 0; buf < length; buf++) {
+ bi = rgd->rd_bits + buf;
+ if (rgrp_block < (bi->bi_start + bi->bi_len) * GFS2_NBBY)
+ break;
+ }
+
+ gfs2_assert(rgd->rd_sbd, buf < length);
+ buf_block = rgrp_block - bi->bi_start * GFS2_NBBY;
+
+ type = gfs2_testbit(rgd,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len, buf_block);
+
+ return type;
+}
+
+/**
+ * rgblk_search - find a block in @old_state, change allocation
+ * state to @new_state
+ * @rgd: the resource group descriptor
+ * @goal: the goal block within the RG (start here to search for avail block)
+ * @old_state: GFS2_BLKST_XXX the before-allocation state to find
+ * @new_state: GFS2_BLKST_XXX the after-allocation block state
+ *
+ * Walk rgrp's bitmap to find bits that represent a block in @old_state.
+ * Add the found bitmap buffer to the transaction.
+ * Set the found bits to @new_state to change block's allocation state.
+ *
+ * This function never fails, because we wouldn't call it unless we
+ * know (from reservation results, etc.) that a block is available.
+ *
+ * Scope of @goal and returned block is just within rgrp, not the whole
+ * filesystem.
+ *
+ * Returns: the block number allocated
+ */
+
+static uint32_t rgblk_search(struct gfs2_rgrpd *rgd, uint32_t goal,
+ unsigned char old_state, unsigned char new_state)
+{
+ struct gfs2_bitmap *bi = NULL;
+ uint32_t length = rgd->rd_ri.ri_length;
+ uint32_t blk = 0;
+ unsigned int buf, x;
+
+ /* Find bitmap block that contains bits for goal block */
+ for (buf = 0; buf < length; buf++) {
+ bi = rgd->rd_bits + buf;
+ if (goal < (bi->bi_start + bi->bi_len) * GFS2_NBBY)
+ break;
+ }
+
+ gfs2_assert(rgd->rd_sbd, buf < length);
+
+ /* Convert scope of "goal" from rgrp-wide to within found bit block */
+ goal -= bi->bi_start * GFS2_NBBY;
+
+ /* Search (up to entire) bitmap in this rgrp for allocatable block.
+ "x <= length", instead of "x < length", because we typically start
+ the search in the middle of a bit block, but if we can't find an
+ allocatable block anywhere else, we want to be able wrap around and
+ search in the first part of our first-searched bit block. */
+ for (x = 0; x <= length; x++) {
+ if (bi->bi_clone)
+ blk = gfs2_bitfit(rgd,
+ bi->bi_clone + bi->bi_offset,
+ bi->bi_len, goal, old_state);
+ else
+ blk = gfs2_bitfit(rgd,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len, goal, old_state);
+ if (blk != BFITNOENT)
+ break;
+
+ /* Try next bitmap block (wrap back to rgrp header if at end) */
+ buf = (buf + 1) % length;
+ bi = rgd->rd_bits + buf;
+ goal = 0;
+ }
+
+ if (gfs2_assert_withdraw(rgd->rd_sbd, x <= length))
+ blk = 0;
+
+ gfs2_trans_add_bh(rgd->rd_gl, bi->bi_bh, 1);
+ gfs2_setbit(rgd,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len, blk, new_state);
+ if (bi->bi_clone)
+ gfs2_setbit(rgd,
+ bi->bi_clone + bi->bi_offset,
+ bi->bi_len, blk, new_state);
+
+ return bi->bi_start * GFS2_NBBY + blk;
+}
+
+/**
+ * rgblk_free - Change alloc state of given block(s)
+ * @sdp: the filesystem
+ * @bstart: the start of a run of blocks to free
+ * @blen: the length of the block run (all must lie within ONE RG!)
+ * @new_state: GFS2_BLKST_XXX the after-allocation block state
+ *
+ * Returns: Resource group containing the block(s)
+ */
+
+static struct gfs2_rgrpd *rgblk_free(struct gfs2_sbd *sdp, uint64_t bstart,
+ uint32_t blen, unsigned char new_state)
+{
+ struct gfs2_rgrpd *rgd;
+ struct gfs2_bitmap *bi = NULL;
+ uint32_t length, rgrp_blk, buf_blk;
+ unsigned int buf;
+
+ rgd = gfs2_blk2rgrpd(sdp, bstart);
+ if (!rgd) {
+ if (gfs2_consist(sdp))
+ fs_err(sdp, "block = %llu\n", bstart);
+ return NULL;
+ }
+
+ length = rgd->rd_ri.ri_length;
+
+ rgrp_blk = bstart - rgd->rd_ri.ri_data0;
+
+ while (blen--) {
+ for (buf = 0; buf < length; buf++) {
+ bi = rgd->rd_bits + buf;
+ if (rgrp_blk < (bi->bi_start + bi->bi_len) * GFS2_NBBY)
+ break;
+ }
+
+ gfs2_assert(rgd->rd_sbd, buf < length);
+
+ buf_blk = rgrp_blk - bi->bi_start * GFS2_NBBY;
+ rgrp_blk++;
+
+ if (!bi->bi_clone) {
+ bi->bi_clone = kmalloc(bi->bi_bh->b_size,
+ GFP_KERNEL | __GFP_NOFAIL);
+ memcpy(bi->bi_clone + bi->bi_offset,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len);
+ }
+ gfs2_trans_add_bh(rgd->rd_gl, bi->bi_bh, 1);
+ gfs2_setbit(rgd,
+ bi->bi_bh->b_data + bi->bi_offset,
+ bi->bi_len, buf_blk, new_state);
+ }
+
+ return rgd;
+}
+
+/**
+ * gfs2_alloc_data - Allocate a data block
+ * @ip: the inode to allocate the data block for
+ *
+ * Returns: the allocated block
+ */
+
+uint64_t gfs2_alloc_data(struct gfs2_inode *ip)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_alloc *al = &ip->i_alloc;
+ struct gfs2_rgrpd *rgd = al->al_rgd;
+ uint32_t goal, blk;
+ uint64_t block;
+
+ if (rgrp_contains_block(&rgd->rd_ri, ip->i_di.di_goal_data))
+ goal = ip->i_di.di_goal_data - rgd->rd_ri.ri_data0;
+ else
+ goal = rgd->rd_last_alloc_data;
+
+ blk = rgblk_search(rgd, goal,
+ GFS2_BLKST_FREE, GFS2_BLKST_USED);
+ rgd->rd_last_alloc_data = blk;
+
+ block = rgd->rd_ri.ri_data0 + blk;
+ ip->i_di.di_goal_data = block;
+
+ gfs2_assert_withdraw(sdp, rgd->rd_rg.rg_free);
+ rgd->rd_rg.rg_free--;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ al->al_alloced++;
+
+ gfs2_statfs_change(sdp, 0, -1, 0);
+ gfs2_quota_change(ip, +1, ip->i_di.di_uid, ip->i_di.di_gid);
+
+ spin_lock(&sdp->sd_rindex_spin);
+ rgd->rd_free_clone--;
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return block;
+}
+
+/**
+ * gfs2_alloc_meta - Allocate a metadata block
+ * @ip: the inode to allocate the metadata block for
+ *
+ * Returns: the allocated block
+ */
+
+uint64_t gfs2_alloc_meta(struct gfs2_inode *ip)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_alloc *al = &ip->i_alloc;
+ struct gfs2_rgrpd *rgd = al->al_rgd;
+ uint32_t goal, blk;
+ uint64_t block;
+
+ if (rgrp_contains_block(&rgd->rd_ri, ip->i_di.di_goal_meta))
+ goal = ip->i_di.di_goal_meta - rgd->rd_ri.ri_data0;
+ else
+ goal = rgd->rd_last_alloc_meta;
+
+ blk = rgblk_search(rgd, goal,
+ GFS2_BLKST_FREE, GFS2_BLKST_USED);
+ rgd->rd_last_alloc_meta = blk;
+
+ block = rgd->rd_ri.ri_data0 + blk;
+ ip->i_di.di_goal_meta = block;
+
+ gfs2_assert_withdraw(sdp, rgd->rd_rg.rg_free);
+ rgd->rd_rg.rg_free--;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ al->al_alloced++;
+
+ gfs2_statfs_change(sdp, 0, -1, 0);
+ gfs2_quota_change(ip, +1, ip->i_di.di_uid, ip->i_di.di_gid);
+ gfs2_trans_add_unrevoke(sdp, block);
+
+ spin_lock(&sdp->sd_rindex_spin);
+ rgd->rd_free_clone--;
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return block;
+}
+
+/**
+ * gfs2_alloc_di - Allocate a dinode
+ * @dip: the directory that the inode is going in
+ *
+ * Returns: the block allocated
+ */
+
+uint64_t gfs2_alloc_di(struct gfs2_inode *dip)
+{
+ struct gfs2_sbd *sdp = dip->i_sbd;
+ struct gfs2_alloc *al = &dip->i_alloc;
+ struct gfs2_rgrpd *rgd = al->al_rgd;
+ uint32_t blk;
+ uint64_t block;
+
+ blk = rgblk_search(rgd, rgd->rd_last_alloc_meta,
+ GFS2_BLKST_FREE, GFS2_BLKST_DINODE);
+
+ rgd->rd_last_alloc_meta = blk;
+
+ block = rgd->rd_ri.ri_data0 + blk;
+
+ gfs2_assert_withdraw(sdp, rgd->rd_rg.rg_free);
+ rgd->rd_rg.rg_free--;
+ rgd->rd_rg.rg_dinodes++;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ al->al_alloced++;
+
+ gfs2_statfs_change(sdp, 0, -1, +1);
+ gfs2_trans_add_unrevoke(sdp, block);
+
+ spin_lock(&sdp->sd_rindex_spin);
+ rgd->rd_free_clone--;
+ spin_unlock(&sdp->sd_rindex_spin);
+
+ return block;
+}
+
+/**
+ * gfs2_free_data - free a contiguous run of data block(s)
+ * @ip: the inode these blocks are being freed from
+ * @bstart: first block of a run of contiguous blocks
+ * @blen: the length of the block run
+ *
+ */
+
+void gfs2_free_data(struct gfs2_inode *ip, uint64_t bstart, uint32_t blen)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_rgrpd *rgd;
+
+ rgd = rgblk_free(sdp, bstart, blen, GFS2_BLKST_FREE);
+ if (!rgd)
+ return;
+
+ rgd->rd_rg.rg_free += blen;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ gfs2_trans_add_rg(rgd);
+
+ gfs2_statfs_change(sdp, 0, +blen, 0);
+ gfs2_quota_change(ip, -(int64_t)blen,
+ ip->i_di.di_uid, ip->i_di.di_gid);
+}
+
+/**
+ * gfs2_free_meta - free a contiguous run of data block(s)
+ * @ip: the inode these blocks are being freed from
+ * @bstart: first block of a run of contiguous blocks
+ * @blen: the length of the block run
+ *
+ */
+
+void gfs2_free_meta(struct gfs2_inode *ip, uint64_t bstart, uint32_t blen)
+{
+ struct gfs2_sbd *sdp = ip->i_sbd;
+ struct gfs2_rgrpd *rgd;
+
+ rgd = rgblk_free(sdp, bstart, blen, GFS2_BLKST_FREE);
+ if (!rgd)
+ return;
+
+ rgd->rd_rg.rg_free += blen;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ gfs2_trans_add_rg(rgd);
+
+ gfs2_statfs_change(sdp, 0, +blen, 0);
+ gfs2_quota_change(ip, -(int64_t)blen,
+ ip->i_di.di_uid, ip->i_di.di_gid);
+ gfs2_meta_wipe(ip, bstart, blen);
+}
+
+void gfs2_free_uninit_di(struct gfs2_rgrpd *rgd, uint64_t blkno)
+{
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
+ struct gfs2_rgrpd *tmp_rgd;
+
+ tmp_rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_FREE);
+ if (!tmp_rgd)
+ return;
+ gfs2_assert_withdraw(sdp, rgd == tmp_rgd);
+
+ if (!rgd->rd_rg.rg_dinodes)
+ gfs2_consist_rgrpd(rgd);
+ rgd->rd_rg.rg_dinodes--;
+ rgd->rd_rg.rg_free++;
+
+ gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
+ gfs2_rgrp_out(&rgd->rd_rg, rgd->rd_bits[0].bi_bh->b_data);
+
+ gfs2_statfs_change(sdp, 0, +1, -1);
+ gfs2_trans_add_rg(rgd);
+}
+
+/**
+ * gfs2_free_uninit_di - free a dinode block
+ * @rgd: the resource group that contains the dinode
+ * @ip: the inode
+ *
+ */
+
+void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip)
+{
+ gfs2_free_uninit_di(rgd, ip->i_num.no_addr);
+ gfs2_quota_change(ip, -1, ip->i_di.di_uid, ip->i_di.di_gid);
+ gfs2_meta_wipe(ip, ip->i_num.no_addr, 1);
+}
+
+/**
+ * gfs2_rlist_add - add a RG to a list of RGs
+ * @sdp: the filesystem
+ * @rlist: the list of resource groups
+ * @block: the block
+ *
+ * Figure out what RG a block belongs to and add that RG to the list
+ *
+ * FIXME: Don't use NOFAIL
+ *
+ */
+
+void gfs2_rlist_add(struct gfs2_sbd *sdp, struct gfs2_rgrp_list *rlist,
+ uint64_t block)
+{
+ struct gfs2_rgrpd *rgd;
+ struct gfs2_rgrpd **tmp;
+ unsigned int new_space;
+ unsigned int x;
+
+ if (gfs2_assert_warn(sdp, !rlist->rl_ghs))
+ return;
+
+ rgd = gfs2_blk2rgrpd(sdp, block);
+ if (!rgd) {
+ if (gfs2_consist(sdp))
+ fs_err(sdp, "block = %llu\n", block);
+ return;
+ }
+
+ for (x = 0; x < rlist->rl_rgrps; x++)
+ if (rlist->rl_rgd[x] == rgd)
+ return;
+
+ if (rlist->rl_rgrps == rlist->rl_space) {
+ new_space = rlist->rl_space + 10;
+
+ tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *),
+ GFP_KERNEL | __GFP_NOFAIL);
+
+ if (rlist->rl_rgd) {
+ memcpy(tmp, rlist->rl_rgd,
+ rlist->rl_space * sizeof(struct gfs2_rgrpd *));
+ kfree(rlist->rl_rgd);
+ }
+
+ rlist->rl_space = new_space;
+ rlist->rl_rgd = tmp;
+ }
+
+ rlist->rl_rgd[rlist->rl_rgrps++] = rgd;
+}
+
+/**
+ * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate
+ * and initialize an array of glock holders for them
+ * @rlist: the list of resource groups
+ * @state: the lock state to acquire the RG lock in
+ * @flags: the modifier flags for the holder structures
+ *
+ * FIXME: Don't use NOFAIL
+ *
+ */
+
+void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state,
+ int flags)
+{
+ unsigned int x;
+
+ rlist->rl_ghs = kcalloc(rlist->rl_rgrps, sizeof(struct gfs2_holder),
+ GFP_KERNEL | __GFP_NOFAIL);
+ for (x = 0; x < rlist->rl_rgrps; x++)
+ gfs2_holder_init(rlist->rl_rgd[x]->rd_gl,
+ state, flags,
+ &rlist->rl_ghs[x]);
+}
+
+/**
+ * gfs2_rlist_free - free a resource group list
+ * @list: the list of resource groups
+ *
+ */
+
+void gfs2_rlist_free(struct gfs2_rgrp_list *rlist)
+{
+ unsigned int x;
+
+ kfree(rlist->rl_rgd);
+
+ if (rlist->rl_ghs) {
+ for (x = 0; x < rlist->rl_rgrps; x++)
+ gfs2_holder_uninit(&rlist->rl_ghs[x]);
+ kfree(rlist->rl_ghs);
+ }
+}
+
--- /dev/null
+++ b/fs/gfs2/rgrp.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+#ifndef __RGRP_DOT_H__
+#define __RGRP_DOT_H__
+
+void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd);
+
+struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, uint64_t blk);
+struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp);
+struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd);
+
+void gfs2_clear_rgrpd(struct gfs2_sbd *sdp);
+int gfs2_rindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ri_gh);
+
+int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd);
+void gfs2_rgrp_bh_hold(struct gfs2_rgrpd *rgd);
+void gfs2_rgrp_bh_put(struct gfs2_rgrpd *rgd);
+
+void gfs2_rgrp_repolish_clones(struct gfs2_rgrpd *rgd);
+
+struct gfs2_alloc *gfs2_alloc_get(struct gfs2_inode *ip);
+void gfs2_alloc_put(struct gfs2_inode *ip);
+
+int gfs2_inplace_reserve_i(struct gfs2_inode *ip,
+ char *file, unsigned int line);
+#define gfs2_inplace_reserve(ip) \
+gfs2_inplace_reserve_i((ip), __FILE__, __LINE__)
+
+void gfs2_inplace_release(struct gfs2_inode *ip);
+
+unsigned char gfs2_get_block_type(struct gfs2_rgrpd *rgd, uint64_t block);
+
+uint64_t gfs2_alloc_data(struct gfs2_inode *ip);
+uint64_t gfs2_alloc_meta(struct gfs2_inode *ip);
+uint64_t gfs2_alloc_di(struct gfs2_inode *ip);
+
+void gfs2_free_data(struct gfs2_inode *ip, uint64_t bstart, uint32_t blen);
+void gfs2_free_meta(struct gfs2_inode *ip, uint64_t bstart, uint32_t blen);
+void gfs2_free_uninit_di(struct gfs2_rgrpd *rgd, uint64_t blkno);
+void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip);
+
+struct gfs2_rgrp_list {
+ unsigned int rl_rgrps;
+ unsigned int rl_space;
+ struct gfs2_rgrpd **rl_rgd;
+ struct gfs2_holder *rl_ghs;
+};
+
+void gfs2_rlist_add(struct gfs2_sbd *sdp, struct gfs2_rgrp_list *rlist,
+ uint64_t block);
+void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state,
+ int flags);
+void gfs2_rlist_free(struct gfs2_rgrp_list *rlist);
+
+#endif /* __RGRP_DOT_H__ */
--- /dev/null
+++ b/fs/gfs2/bits.c
@@ -0,0 +1,182 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+/*
+ * These routines are used by the resource group routines (rgrp.c)
+ * to keep track of block allocation. Each block is represented by two
+ * bits. One bit indicates whether or not the block is used. (1=used,
+ * 0=free) The other bit indicates whether or not the block contains a
+ * dinode or not. (1=dinode, 0=not-dinode) So, each byte represents
+ * GFS2_NBBY (i.e. 4) blocks.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/gfs2_ondisk.h>
+#include <asm/semaphore.h>
+
+#include "gfs2.h"
+#include "lm_interface.h"
+#include "incore.h"
+#include "bits.h"
+#include "util.h"
+
+static const char valid_change[16] = {
+ /* current */
+ /* n */ 0, 1, 0, 1,
+ /* e */ 1, 0, 0, 0,
+ /* w */ 0, 0, 0, 0,
+ 1, 0, 0, 0
+};
+
+/**
+ * gfs2_setbit - Set a bit in the bitmaps
+ * @buffer: the buffer that holds the bitmaps
+ * @buflen: the length (in bytes) of the buffer
+ * @block: the block to set
+ * @new_state: the new state of the block
+ *
+ */
+
+void gfs2_setbit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
+ unsigned int buflen, uint32_t block, unsigned char new_state)
+{
+ unsigned char *byte, *end, cur_state;
+ unsigned int bit;
+
+ byte = buffer + (block / GFS2_NBBY);
+ bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
+ end = buffer + buflen;
+
+ gfs2_assert(rgd->rd_sbd, byte < end);
+
+ cur_state = (*byte >> bit) & GFS2_BIT_MASK;
+
+ if (valid_change[new_state * 4 + cur_state]) {
+ *byte ^= cur_state << bit;
+ *byte |= new_state << bit;
+ } else
+ gfs2_consist_rgrpd(rgd);
+}
+
+/**
+ * gfs2_testbit - test a bit in the bitmaps
+ * @buffer: the buffer that holds the bitmaps
+ * @buflen: the length (in bytes) of the buffer
+ * @block: the block to read
+ *
+ */
+
+unsigned char gfs2_testbit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
+ unsigned int buflen, uint32_t block)
+{
+ unsigned char *byte, *end, cur_state;
+ unsigned int bit;
+
+ byte = buffer + (block / GFS2_NBBY);
+ bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
+ end = buffer + buflen;
+
+ gfs2_assert(rgd->rd_sbd, byte < end);
+
+ cur_state = (*byte >> bit) & GFS2_BIT_MASK;
+
+ return cur_state;
+}
+
+/**
+ * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
+ * a block in a given allocation state.
+ * @buffer: the buffer that holds the bitmaps
+ * @buflen: the length (in bytes) of the buffer
+ * @goal: start search at this block's bit-pair (within @buffer)
+ * @old_state: GFS2_BLKST_XXX the state of the block we're looking for;
+ * bit 0 = alloc(1)/free(0), bit 1 = meta(1)/data(0)
+ *
+ * Scope of @goal and returned block number is only within this bitmap buffer,
+ * not entire rgrp or filesystem. @buffer will be offset from the actual
+ * beginning of a bitmap block buffer, skipping any header structures.
+ *
+ * Return: the block number (bitmap buffer scope) that was found
+ */
+
+uint32_t gfs2_bitfit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
+ unsigned int buflen, uint32_t goal,
+ unsigned char old_state)
+{
+ unsigned char *byte, *end, alloc;
+ uint32_t blk = goal;
+ unsigned int bit;
+
+ byte = buffer + (goal / GFS2_NBBY);
+ bit = (goal % GFS2_NBBY) * GFS2_BIT_SIZE;
+ end = buffer + buflen;
+ alloc = (old_state & 1) ? 0 : 0x55;
+
+ while (byte < end) {
+ if ((*byte & 0x55) == alloc) {
+ blk += (8 - bit) >> 1;
+
+ bit = 0;
+ byte++;
+
+ continue;
+ }
+
+ if (((*byte >> bit) & GFS2_BIT_MASK) == old_state)
+ return blk;
+
+ bit += GFS2_BIT_SIZE;
+ if (bit >= 8) {
+ bit = 0;
+ byte++;
+ }
+
+ blk++;
+ }
+
+ return BFITNOENT;
+}
+
+/**
+ * gfs2_bitcount - count the number of bits in a certain state
+ * @buffer: the buffer that holds the bitmaps
+ * @buflen: the length (in bytes) of the buffer
+ * @state: the state of the block we're looking for
+ *
+ * Returns: The number of bits
+ */
+
+uint32_t gfs2_bitcount(struct gfs2_rgrpd *rgd, unsigned char *buffer,
+ unsigned int buflen, unsigned char state)
+{
+ unsigned char *byte = buffer;
+ unsigned char *end = buffer + buflen;
+ unsigned char state1 = state << 2;
+ unsigned char state2 = state << 4;
+ unsigned char state3 = state << 6;
+ uint32_t count = 0;
+
+ for (; byte < end; byte++) {
+ if (((*byte) & 0x03) == state)
+ count++;
+ if (((*byte) & 0x0C) == state1)
+ count++;
+ if (((*byte) & 0x30) == state2)
+ count++;
+ if (((*byte) & 0xC0) == state3)
+ count++;
+ }
+
+ return count;
+}
+
--- /dev/null
+++ b/fs/gfs2/bits.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+#ifndef __BITS_DOT_H__
+#define __BITS_DOT_H__
+
+#define BFITNOENT 0xFFFFFFFF
+
+void gfs2_setbit(struct gfs2_rgrpd *rgd,
+ unsigned char *buffer, unsigned int buflen,
+ uint32_t block, unsigned char new_state);
+unsigned char gfs2_testbit(struct gfs2_rgrpd *rgd,
+ unsigned char *buffer, unsigned int buflen,
+ uint32_t block);
+uint32_t gfs2_bitfit(struct gfs2_rgrpd *rgd,
+ unsigned char *buffer, unsigned int buflen,
+ uint32_t goal, unsigned char old_state);
+uint32_t gfs2_bitcount(struct gfs2_rgrpd *rgd,
+ unsigned char *buffer, unsigned int buflen,
+ unsigned char state);
+
+#endif /* __BITS_DOT_H__ */

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