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-rw-r--r--fs/ocfs2/extent_map.c1041
1 files changed, 1041 insertions, 0 deletions
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
new file mode 100644
index 000000000..06cb96462
--- /dev/null
+++ b/fs/ocfs2/extent_map.c
@@ -0,0 +1,1041 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * extent_map.c
+ *
+ * Block/Cluster mapping functions
+ *
+ * Copyright (C) 2004 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License, version 2, as published by the Free Software Foundation.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/fiemap.h>
+
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "dlmglue.h"
+#include "extent_map.h"
+#include "inode.h"
+#include "super.h"
+#include "symlink.h"
+#include "aops.h"
+#include "ocfs2_trace.h"
+
+#include "buffer_head_io.h"
+
+/*
+ * The extent caching implementation is intentionally trivial.
+ *
+ * We only cache a small number of extents stored directly on the
+ * inode, so linear order operations are acceptable. If we ever want
+ * to increase the size of the extent map, then these algorithms must
+ * get smarter.
+ */
+
+void ocfs2_extent_map_init(struct inode *inode)
+{
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+
+ oi->ip_extent_map.em_num_items = 0;
+ INIT_LIST_HEAD(&oi->ip_extent_map.em_list);
+}
+
+static void __ocfs2_extent_map_lookup(struct ocfs2_extent_map *em,
+ unsigned int cpos,
+ struct ocfs2_extent_map_item **ret_emi)
+{
+ unsigned int range;
+ struct ocfs2_extent_map_item *emi;
+
+ *ret_emi = NULL;
+
+ list_for_each_entry(emi, &em->em_list, ei_list) {
+ range = emi->ei_cpos + emi->ei_clusters;
+
+ if (cpos >= emi->ei_cpos && cpos < range) {
+ list_move(&emi->ei_list, &em->em_list);
+
+ *ret_emi = emi;
+ break;
+ }
+ }
+}
+
+static int ocfs2_extent_map_lookup(struct inode *inode, unsigned int cpos,
+ unsigned int *phys, unsigned int *len,
+ unsigned int *flags)
+{
+ unsigned int coff;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_extent_map_item *emi;
+
+ spin_lock(&oi->ip_lock);
+
+ __ocfs2_extent_map_lookup(&oi->ip_extent_map, cpos, &emi);
+ if (emi) {
+ coff = cpos - emi->ei_cpos;
+ *phys = emi->ei_phys + coff;
+ if (len)
+ *len = emi->ei_clusters - coff;
+ if (flags)
+ *flags = emi->ei_flags;
+ }
+
+ spin_unlock(&oi->ip_lock);
+
+ if (emi == NULL)
+ return -ENOENT;
+
+ return 0;
+}
+
+/*
+ * Forget about all clusters equal to or greater than cpos.
+ */
+void ocfs2_extent_map_trunc(struct inode *inode, unsigned int cpos)
+{
+ struct ocfs2_extent_map_item *emi, *n;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_extent_map *em = &oi->ip_extent_map;
+ LIST_HEAD(tmp_list);
+ unsigned int range;
+
+ spin_lock(&oi->ip_lock);
+ list_for_each_entry_safe(emi, n, &em->em_list, ei_list) {
+ if (emi->ei_cpos >= cpos) {
+ /* Full truncate of this record. */
+ list_move(&emi->ei_list, &tmp_list);
+ BUG_ON(em->em_num_items == 0);
+ em->em_num_items--;
+ continue;
+ }
+
+ range = emi->ei_cpos + emi->ei_clusters;
+ if (range > cpos) {
+ /* Partial truncate */
+ emi->ei_clusters = cpos - emi->ei_cpos;
+ }
+ }
+ spin_unlock(&oi->ip_lock);
+
+ list_for_each_entry_safe(emi, n, &tmp_list, ei_list) {
+ list_del(&emi->ei_list);
+ kfree(emi);
+ }
+}
+
+/*
+ * Is any part of emi2 contained within emi1
+ */
+static int ocfs2_ei_is_contained(struct ocfs2_extent_map_item *emi1,
+ struct ocfs2_extent_map_item *emi2)
+{
+ unsigned int range1, range2;
+
+ /*
+ * Check if logical start of emi2 is inside emi1
+ */
+ range1 = emi1->ei_cpos + emi1->ei_clusters;
+ if (emi2->ei_cpos >= emi1->ei_cpos && emi2->ei_cpos < range1)
+ return 1;
+
+ /*
+ * Check if logical end of emi2 is inside emi1
+ */
+ range2 = emi2->ei_cpos + emi2->ei_clusters;
+ if (range2 > emi1->ei_cpos && range2 <= range1)
+ return 1;
+
+ return 0;
+}
+
+static void ocfs2_copy_emi_fields(struct ocfs2_extent_map_item *dest,
+ struct ocfs2_extent_map_item *src)
+{
+ dest->ei_cpos = src->ei_cpos;
+ dest->ei_phys = src->ei_phys;
+ dest->ei_clusters = src->ei_clusters;
+ dest->ei_flags = src->ei_flags;
+}
+
+/*
+ * Try to merge emi with ins. Returns 1 if merge succeeds, zero
+ * otherwise.
+ */
+static int ocfs2_try_to_merge_extent_map(struct ocfs2_extent_map_item *emi,
+ struct ocfs2_extent_map_item *ins)
+{
+ /*
+ * Handle contiguousness
+ */
+ if (ins->ei_phys == (emi->ei_phys + emi->ei_clusters) &&
+ ins->ei_cpos == (emi->ei_cpos + emi->ei_clusters) &&
+ ins->ei_flags == emi->ei_flags) {
+ emi->ei_clusters += ins->ei_clusters;
+ return 1;
+ } else if ((ins->ei_phys + ins->ei_clusters) == emi->ei_phys &&
+ (ins->ei_cpos + ins->ei_clusters) == emi->ei_cpos &&
+ ins->ei_flags == emi->ei_flags) {
+ emi->ei_phys = ins->ei_phys;
+ emi->ei_cpos = ins->ei_cpos;
+ emi->ei_clusters += ins->ei_clusters;
+ return 1;
+ }
+
+ /*
+ * Overlapping extents - this shouldn't happen unless we've
+ * split an extent to change it's flags. That is exceedingly
+ * rare, so there's no sense in trying to optimize it yet.
+ */
+ if (ocfs2_ei_is_contained(emi, ins) ||
+ ocfs2_ei_is_contained(ins, emi)) {
+ ocfs2_copy_emi_fields(emi, ins);
+ return 1;
+ }
+
+ /* No merge was possible. */
+ return 0;
+}
+
+/*
+ * In order to reduce complexity on the caller, this insert function
+ * is intentionally liberal in what it will accept.
+ *
+ * The only rule is that the truncate call *must* be used whenever
+ * records have been deleted. This avoids inserting overlapping
+ * records with different physical mappings.
+ */
+void ocfs2_extent_map_insert_rec(struct inode *inode,
+ struct ocfs2_extent_rec *rec)
+{
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_extent_map *em = &oi->ip_extent_map;
+ struct ocfs2_extent_map_item *emi, *new_emi = NULL;
+ struct ocfs2_extent_map_item ins;
+
+ ins.ei_cpos = le32_to_cpu(rec->e_cpos);
+ ins.ei_phys = ocfs2_blocks_to_clusters(inode->i_sb,
+ le64_to_cpu(rec->e_blkno));
+ ins.ei_clusters = le16_to_cpu(rec->e_leaf_clusters);
+ ins.ei_flags = rec->e_flags;
+
+search:
+ spin_lock(&oi->ip_lock);
+
+ list_for_each_entry(emi, &em->em_list, ei_list) {
+ if (ocfs2_try_to_merge_extent_map(emi, &ins)) {
+ list_move(&emi->ei_list, &em->em_list);
+ spin_unlock(&oi->ip_lock);
+ goto out;
+ }
+ }
+
+ /*
+ * No item could be merged.
+ *
+ * Either allocate and add a new item, or overwrite the last recently
+ * inserted.
+ */
+
+ if (em->em_num_items < OCFS2_MAX_EXTENT_MAP_ITEMS) {
+ if (new_emi == NULL) {
+ spin_unlock(&oi->ip_lock);
+
+ new_emi = kmalloc(sizeof(*new_emi), GFP_NOFS);
+ if (new_emi == NULL)
+ goto out;
+
+ goto search;
+ }
+
+ ocfs2_copy_emi_fields(new_emi, &ins);
+ list_add(&new_emi->ei_list, &em->em_list);
+ em->em_num_items++;
+ new_emi = NULL;
+ } else {
+ BUG_ON(list_empty(&em->em_list) || em->em_num_items == 0);
+ emi = list_entry(em->em_list.prev,
+ struct ocfs2_extent_map_item, ei_list);
+ list_move(&emi->ei_list, &em->em_list);
+ ocfs2_copy_emi_fields(emi, &ins);
+ }
+
+ spin_unlock(&oi->ip_lock);
+
+out:
+ kfree(new_emi);
+}
+
+static int ocfs2_last_eb_is_empty(struct inode *inode,
+ struct ocfs2_dinode *di)
+{
+ int ret, next_free;
+ u64 last_eb_blk = le64_to_cpu(di->i_last_eb_blk);
+ struct buffer_head *eb_bh = NULL;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+
+ ret = ocfs2_read_extent_block(INODE_CACHE(inode), last_eb_blk, &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has non zero tree depth in leaf block %llu\n",
+ inode->i_ino,
+ (unsigned long long)eb_bh->b_blocknr);
+ ret = -EROFS;
+ goto out;
+ }
+
+ next_free = le16_to_cpu(el->l_next_free_rec);
+
+ if (next_free == 0 ||
+ (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0])))
+ ret = 1;
+
+out:
+ brelse(eb_bh);
+ return ret;
+}
+
+/*
+ * Return the 1st index within el which contains an extent start
+ * larger than v_cluster.
+ */
+static int ocfs2_search_for_hole_index(struct ocfs2_extent_list *el,
+ u32 v_cluster)
+{
+ int i;
+ struct ocfs2_extent_rec *rec;
+
+ for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
+ rec = &el->l_recs[i];
+
+ if (v_cluster < le32_to_cpu(rec->e_cpos))
+ break;
+ }
+
+ return i;
+}
+
+/*
+ * Figure out the size of a hole which starts at v_cluster within the given
+ * extent list.
+ *
+ * If there is no more allocation past v_cluster, we return the maximum
+ * cluster size minus v_cluster.
+ *
+ * If we have in-inode extents, then el points to the dinode list and
+ * eb_bh is NULL. Otherwise, eb_bh should point to the extent block
+ * containing el.
+ */
+int ocfs2_figure_hole_clusters(struct ocfs2_caching_info *ci,
+ struct ocfs2_extent_list *el,
+ struct buffer_head *eb_bh,
+ u32 v_cluster,
+ u32 *num_clusters)
+{
+ int ret, i;
+ struct buffer_head *next_eb_bh = NULL;
+ struct ocfs2_extent_block *eb, *next_eb;
+
+ i = ocfs2_search_for_hole_index(el, v_cluster);
+
+ if (i == le16_to_cpu(el->l_next_free_rec) && eb_bh) {
+ eb = (struct ocfs2_extent_block *)eb_bh->b_data;
+
+ /*
+ * Check the next leaf for any extents.
+ */
+
+ if (le64_to_cpu(eb->h_next_leaf_blk) == 0ULL)
+ goto no_more_extents;
+
+ ret = ocfs2_read_extent_block(ci,
+ le64_to_cpu(eb->h_next_leaf_blk),
+ &next_eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ next_eb = (struct ocfs2_extent_block *)next_eb_bh->b_data;
+ el = &next_eb->h_list;
+ i = ocfs2_search_for_hole_index(el, v_cluster);
+ }
+
+no_more_extents:
+ if (i == le16_to_cpu(el->l_next_free_rec)) {
+ /*
+ * We're at the end of our existing allocation. Just
+ * return the maximum number of clusters we could
+ * possibly allocate.
+ */
+ *num_clusters = UINT_MAX - v_cluster;
+ } else {
+ *num_clusters = le32_to_cpu(el->l_recs[i].e_cpos) - v_cluster;
+ }
+
+ ret = 0;
+out:
+ brelse(next_eb_bh);
+ return ret;
+}
+
+static int ocfs2_get_clusters_nocache(struct inode *inode,
+ struct buffer_head *di_bh,
+ u32 v_cluster, unsigned int *hole_len,
+ struct ocfs2_extent_rec *ret_rec,
+ unsigned int *is_last)
+{
+ int i, ret, tree_height, len;
+ struct ocfs2_dinode *di;
+ struct ocfs2_extent_block *uninitialized_var(eb);
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_rec *rec;
+ struct buffer_head *eb_bh = NULL;
+
+ memset(ret_rec, 0, sizeof(*ret_rec));
+ if (is_last)
+ *is_last = 0;
+
+ di = (struct ocfs2_dinode *) di_bh->b_data;
+ el = &di->id2.i_list;
+ tree_height = le16_to_cpu(el->l_tree_depth);
+
+ if (tree_height > 0) {
+ ret = ocfs2_find_leaf(INODE_CACHE(inode), el, v_cluster,
+ &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has non zero tree depth in leaf block %llu\n",
+ inode->i_ino,
+ (unsigned long long)eb_bh->b_blocknr);
+ ret = -EROFS;
+ goto out;
+ }
+ }
+
+ i = ocfs2_search_extent_list(el, v_cluster);
+ if (i == -1) {
+ /*
+ * Holes can be larger than the maximum size of an
+ * extent, so we return their lengths in a separate
+ * field.
+ */
+ if (hole_len) {
+ ret = ocfs2_figure_hole_clusters(INODE_CACHE(inode),
+ el, eb_bh,
+ v_cluster, &len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ *hole_len = len;
+ }
+ goto out_hole;
+ }
+
+ rec = &el->l_recs[i];
+
+ BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
+
+ if (!rec->e_blkno) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has bad extent record (%u, %u, 0)\n",
+ inode->i_ino,
+ le32_to_cpu(rec->e_cpos),
+ ocfs2_rec_clusters(el, rec));
+ ret = -EROFS;
+ goto out;
+ }
+
+ *ret_rec = *rec;
+
+ /*
+ * Checking for last extent is potentially expensive - we
+ * might have to look at the next leaf over to see if it's
+ * empty.
+ *
+ * The first two checks are to see whether the caller even
+ * cares for this information, and if the extent is at least
+ * the last in it's list.
+ *
+ * If those hold true, then the extent is last if any of the
+ * additional conditions hold true:
+ * - Extent list is in-inode
+ * - Extent list is right-most
+ * - Extent list is 2nd to rightmost, with empty right-most
+ */
+ if (is_last) {
+ if (i == (le16_to_cpu(el->l_next_free_rec) - 1)) {
+ if (tree_height == 0)
+ *is_last = 1;
+ else if (eb->h_blkno == di->i_last_eb_blk)
+ *is_last = 1;
+ else if (eb->h_next_leaf_blk == di->i_last_eb_blk) {
+ ret = ocfs2_last_eb_is_empty(inode, di);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ if (ret == 1)
+ *is_last = 1;
+ }
+ }
+ }
+
+out_hole:
+ ret = 0;
+out:
+ brelse(eb_bh);
+ return ret;
+}
+
+static void ocfs2_relative_extent_offsets(struct super_block *sb,
+ u32 v_cluster,
+ struct ocfs2_extent_rec *rec,
+ u32 *p_cluster, u32 *num_clusters)
+
+{
+ u32 coff = v_cluster - le32_to_cpu(rec->e_cpos);
+
+ *p_cluster = ocfs2_blocks_to_clusters(sb, le64_to_cpu(rec->e_blkno));
+ *p_cluster = *p_cluster + coff;
+
+ if (num_clusters)
+ *num_clusters = le16_to_cpu(rec->e_leaf_clusters) - coff;
+}
+
+int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster,
+ u32 *p_cluster, u32 *num_clusters,
+ struct ocfs2_extent_list *el,
+ unsigned int *extent_flags)
+{
+ int ret = 0, i;
+ struct buffer_head *eb_bh = NULL;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_rec *rec;
+ u32 coff;
+
+ if (el->l_tree_depth) {
+ ret = ocfs2_find_leaf(INODE_CACHE(inode), el, v_cluster,
+ &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has non zero tree depth in xattr leaf block %llu\n",
+ inode->i_ino,
+ (unsigned long long)eb_bh->b_blocknr);
+ ret = -EROFS;
+ goto out;
+ }
+ }
+
+ i = ocfs2_search_extent_list(el, v_cluster);
+ if (i == -1) {
+ ret = -EROFS;
+ mlog_errno(ret);
+ goto out;
+ } else {
+ rec = &el->l_recs[i];
+ BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
+
+ if (!rec->e_blkno) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has bad extent record (%u, %u, 0) in xattr\n",
+ inode->i_ino,
+ le32_to_cpu(rec->e_cpos),
+ ocfs2_rec_clusters(el, rec));
+ ret = -EROFS;
+ goto out;
+ }
+ coff = v_cluster - le32_to_cpu(rec->e_cpos);
+ *p_cluster = ocfs2_blocks_to_clusters(inode->i_sb,
+ le64_to_cpu(rec->e_blkno));
+ *p_cluster = *p_cluster + coff;
+ if (num_clusters)
+ *num_clusters = ocfs2_rec_clusters(el, rec) - coff;
+
+ if (extent_flags)
+ *extent_flags = rec->e_flags;
+ }
+out:
+ if (eb_bh)
+ brelse(eb_bh);
+ return ret;
+}
+
+int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
+ u32 *p_cluster, u32 *num_clusters,
+ unsigned int *extent_flags)
+{
+ int ret;
+ unsigned int uninitialized_var(hole_len), flags = 0;
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_extent_rec rec;
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ ret = -ERANGE;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_extent_map_lookup(inode, v_cluster, p_cluster,
+ num_clusters, extent_flags);
+ if (ret == 0)
+ goto out;
+
+ ret = ocfs2_read_inode_block(inode, &di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_get_clusters_nocache(inode, di_bh, v_cluster, &hole_len,
+ &rec, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (rec.e_blkno == 0ULL) {
+ /*
+ * A hole was found. Return some canned values that
+ * callers can key on. If asked for, num_clusters will
+ * be populated with the size of the hole.
+ */
+ *p_cluster = 0;
+ if (num_clusters) {
+ *num_clusters = hole_len;
+ }
+ } else {
+ ocfs2_relative_extent_offsets(inode->i_sb, v_cluster, &rec,
+ p_cluster, num_clusters);
+ flags = rec.e_flags;
+
+ ocfs2_extent_map_insert_rec(inode, &rec);
+ }
+
+ if (extent_flags)
+ *extent_flags = flags;
+
+out:
+ brelse(di_bh);
+ return ret;
+}
+
+/*
+ * This expects alloc_sem to be held. The allocation cannot change at
+ * all while the map is in the process of being updated.
+ */
+int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
+ u64 *ret_count, unsigned int *extent_flags)
+{
+ int ret;
+ int bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
+ u32 cpos, num_clusters, p_cluster;
+ u64 boff = 0;
+
+ cpos = ocfs2_blocks_to_clusters(inode->i_sb, v_blkno);
+
+ ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters,
+ extent_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * p_cluster == 0 indicates a hole.
+ */
+ if (p_cluster) {
+ boff = ocfs2_clusters_to_blocks(inode->i_sb, p_cluster);
+ boff += (v_blkno & (u64)(bpc - 1));
+ }
+
+ *p_blkno = boff;
+
+ if (ret_count) {
+ *ret_count = ocfs2_clusters_to_blocks(inode->i_sb, num_clusters);
+ *ret_count -= v_blkno & (u64)(bpc - 1);
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * The ocfs2_fiemap_inline() may be a little bit misleading, since
+ * it not only handles the fiemap for inlined files, but also deals
+ * with the fast symlink, cause they have no difference for extent
+ * mapping per se.
+ */
+static int ocfs2_fiemap_inline(struct inode *inode, struct buffer_head *di_bh,
+ struct fiemap_extent_info *fieinfo,
+ u64 map_start)
+{
+ int ret;
+ unsigned int id_count;
+ struct ocfs2_dinode *di;
+ u64 phys;
+ u32 flags = FIEMAP_EXTENT_DATA_INLINE|FIEMAP_EXTENT_LAST;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+
+ di = (struct ocfs2_dinode *)di_bh->b_data;
+ if (ocfs2_inode_is_fast_symlink(inode))
+ id_count = ocfs2_fast_symlink_chars(inode->i_sb);
+ else
+ id_count = le16_to_cpu(di->id2.i_data.id_count);
+
+ if (map_start < id_count) {
+ phys = oi->ip_blkno << inode->i_sb->s_blocksize_bits;
+ if (ocfs2_inode_is_fast_symlink(inode))
+ phys += offsetof(struct ocfs2_dinode, id2.i_symlink);
+ else
+ phys += offsetof(struct ocfs2_dinode,
+ id2.i_data.id_data);
+
+ ret = fiemap_fill_next_extent(fieinfo, 0, phys, id_count,
+ flags);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+#define OCFS2_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
+
+int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+ u64 map_start, u64 map_len)
+{
+ int ret, is_last;
+ u32 mapping_end, cpos;
+ unsigned int hole_size;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ u64 len_bytes, phys_bytes, virt_bytes;
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_extent_rec rec;
+
+ ret = fiemap_check_flags(fieinfo, OCFS2_FIEMAP_FLAGS);
+ if (ret)
+ return ret;
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 0);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+ /*
+ * Handle inline-data and fast symlink separately.
+ */
+ if ((OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) ||
+ ocfs2_inode_is_fast_symlink(inode)) {
+ ret = ocfs2_fiemap_inline(inode, di_bh, fieinfo, map_start);
+ goto out_unlock;
+ }
+
+ cpos = map_start >> osb->s_clustersize_bits;
+ mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
+ map_start + map_len);
+ is_last = 0;
+ while (cpos < mapping_end && !is_last) {
+ u32 fe_flags;
+
+ ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
+ &hole_size, &rec, &is_last);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ if (rec.e_blkno == 0ULL) {
+ cpos += hole_size;
+ continue;
+ }
+
+ fe_flags = 0;
+ if (rec.e_flags & OCFS2_EXT_UNWRITTEN)
+ fe_flags |= FIEMAP_EXTENT_UNWRITTEN;
+ if (rec.e_flags & OCFS2_EXT_REFCOUNTED)
+ fe_flags |= FIEMAP_EXTENT_SHARED;
+ if (is_last)
+ fe_flags |= FIEMAP_EXTENT_LAST;
+ len_bytes = (u64)le16_to_cpu(rec.e_leaf_clusters) << osb->s_clustersize_bits;
+ phys_bytes = le64_to_cpu(rec.e_blkno) << osb->sb->s_blocksize_bits;
+ virt_bytes = (u64)le32_to_cpu(rec.e_cpos) << osb->s_clustersize_bits;
+
+ ret = fiemap_fill_next_extent(fieinfo, virt_bytes, phys_bytes,
+ len_bytes, fe_flags);
+ if (ret)
+ break;
+
+ cpos = le32_to_cpu(rec.e_cpos)+ le16_to_cpu(rec.e_leaf_clusters);
+ }
+
+ if (ret > 0)
+ ret = 0;
+
+out_unlock:
+ brelse(di_bh);
+
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+ ocfs2_inode_unlock(inode, 0);
+out:
+
+ return ret;
+}
+
+/* Is IO overwriting allocated blocks? */
+int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh,
+ u64 map_start, u64 map_len)
+{
+ int ret = 0, is_last;
+ u32 mapping_end, cpos;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_extent_rec rec;
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len))
+ return ret;
+ else
+ return -EAGAIN;
+ }
+
+ cpos = map_start >> osb->s_clustersize_bits;
+ mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
+ map_start + map_len);
+ is_last = 0;
+ while (cpos < mapping_end && !is_last) {
+ ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
+ NULL, &rec, &is_last);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (rec.e_blkno == 0ULL)
+ break;
+
+ if (rec.e_flags & OCFS2_EXT_REFCOUNTED)
+ break;
+
+ cpos = le32_to_cpu(rec.e_cpos) +
+ le16_to_cpu(rec.e_leaf_clusters);
+ }
+
+ if (cpos < mapping_end)
+ ret = -EAGAIN;
+out:
+ return ret;
+}
+
+int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int whence)
+{
+ struct inode *inode = file->f_mapping->host;
+ int ret;
+ unsigned int is_last = 0, is_data = 0;
+ u16 cs_bits = OCFS2_SB(inode->i_sb)->s_clustersize_bits;
+ u32 cpos, cend, clen, hole_size;
+ u64 extoff, extlen;
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_extent_rec rec;
+
+ BUG_ON(whence != SEEK_DATA && whence != SEEK_HOLE);
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 0);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+ if (*offset >= i_size_read(inode)) {
+ ret = -ENXIO;
+ goto out_unlock;
+ }
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ if (whence == SEEK_HOLE)
+ *offset = i_size_read(inode);
+ goto out_unlock;
+ }
+
+ clen = 0;
+ cpos = *offset >> cs_bits;
+ cend = ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
+
+ while (cpos < cend && !is_last) {
+ ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos, &hole_size,
+ &rec, &is_last);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ extoff = cpos;
+ extoff <<= cs_bits;
+
+ if (rec.e_blkno == 0ULL) {
+ clen = hole_size;
+ is_data = 0;
+ } else {
+ clen = le16_to_cpu(rec.e_leaf_clusters) -
+ (cpos - le32_to_cpu(rec.e_cpos));
+ is_data = (rec.e_flags & OCFS2_EXT_UNWRITTEN) ? 0 : 1;
+ }
+
+ if ((!is_data && whence == SEEK_HOLE) ||
+ (is_data && whence == SEEK_DATA)) {
+ if (extoff > *offset)
+ *offset = extoff;
+ goto out_unlock;
+ }
+
+ if (!is_last)
+ cpos += clen;
+ }
+
+ if (whence == SEEK_HOLE) {
+ extoff = cpos;
+ extoff <<= cs_bits;
+ extlen = clen;
+ extlen <<= cs_bits;
+
+ if ((extoff + extlen) > i_size_read(inode))
+ extlen = i_size_read(inode) - extoff;
+ extoff += extlen;
+ if (extoff > *offset)
+ *offset = extoff;
+ goto out_unlock;
+ }
+
+ ret = -ENXIO;
+
+out_unlock:
+
+ brelse(di_bh);
+
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+ ocfs2_inode_unlock(inode, 0);
+out:
+ return ret;
+}
+
+int ocfs2_read_virt_blocks(struct inode *inode, u64 v_block, int nr,
+ struct buffer_head *bhs[], int flags,
+ int (*validate)(struct super_block *sb,
+ struct buffer_head *bh))
+{
+ int rc = 0;
+ u64 p_block, p_count;
+ int i, count, done = 0;
+
+ trace_ocfs2_read_virt_blocks(
+ inode, (unsigned long long)v_block, nr, bhs, flags,
+ validate);
+
+ if (((v_block + nr - 1) << inode->i_sb->s_blocksize_bits) >=
+ i_size_read(inode)) {
+ BUG_ON(!(flags & OCFS2_BH_READAHEAD));
+ goto out;
+ }
+
+ while (done < nr) {
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+ rc = ocfs2_extent_map_get_blocks(inode, v_block + done,
+ &p_block, &p_count, NULL);
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+ if (rc) {
+ mlog_errno(rc);
+ break;
+ }
+
+ if (!p_block) {
+ rc = -EIO;
+ mlog(ML_ERROR,
+ "Inode #%llu contains a hole at offset %llu\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)(v_block + done) <<
+ inode->i_sb->s_blocksize_bits);
+ break;
+ }
+
+ count = nr - done;
+ if (p_count < count)
+ count = p_count;
+
+ /*
+ * If the caller passed us bhs, they should have come
+ * from a previous readahead call to this function. Thus,
+ * they should have the right b_blocknr.
+ */
+ for (i = 0; i < count; i++) {
+ if (!bhs[done + i])
+ continue;
+ BUG_ON(bhs[done + i]->b_blocknr != (p_block + i));
+ }
+
+ rc = ocfs2_read_blocks(INODE_CACHE(inode), p_block, count,
+ bhs + done, flags, validate);
+ if (rc) {
+ mlog_errno(rc);
+ break;
+ }
+ done += count;
+ }
+
+out:
+ return rc;
+}
+
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 17:10:21 +0000