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@@ -0,0 +1,645 @@
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+/*
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+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
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+ * Copyright (c) 2013 Red Hat, Inc.
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+ * All Rights Reserved.
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+ *
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+ * This program is free software; you can redistribute it and/or
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+ * modify it under the terms of the GNU General Public License as
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+ * published by the Free Software Foundation.
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+ *
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+ * This program is distributed in the hope that it would be useful,
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+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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+ * GNU General Public License for more details.
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+ *
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+ * You should have received a copy of the GNU General Public License
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+ * along with this program; if not, write the Free Software Foundation,
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+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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+ */
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+#include "xfs.h"
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+#include "xfs_fs.h"
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+#include "xfs_types.h"
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+#include "xfs_bit.h"
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+#include "xfs_log.h"
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+#include "xfs_trans.h"
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+#include "xfs_sb.h"
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+#include "xfs_ag.h"
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+#include "xfs_mount.h"
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+#include "xfs_da_btree.h"
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+#include "xfs_bmap_btree.h"
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+#include "xfs_dinode.h"
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+#include "xfs_inode.h"
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+#include "xfs_dir2_format.h"
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+#include "xfs_dir2_priv.h"
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+#include "xfs_error.h"
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+#include "xfs_trace.h"
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+#include "xfs_bmap.h"
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+
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+STATIC int
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+xfs_dir2_sf_getdents(
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+ xfs_inode_t *dp, /* incore directory inode */
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+ struct dir_context *ctx)
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+{
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+ int i; /* shortform entry number */
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+ xfs_mount_t *mp; /* filesystem mount point */
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+ xfs_dir2_dataptr_t off; /* current entry's offset */
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+ xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */
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+ xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
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+ xfs_dir2_dataptr_t dot_offset;
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+ xfs_dir2_dataptr_t dotdot_offset;
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+ xfs_ino_t ino;
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+
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+ mp = dp->i_mount;
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+
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+ ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
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+ /*
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+ * Give up if the directory is way too short.
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+ */
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+ if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
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+ ASSERT(XFS_FORCED_SHUTDOWN(mp));
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+ return XFS_ERROR(EIO);
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+ }
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+
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+ ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
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+ ASSERT(dp->i_df.if_u1.if_data != NULL);
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+
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+ sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
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+
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+ ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
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+
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+ /*
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+ * If the block number in the offset is out of range, we're done.
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+ */
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+ if (xfs_dir2_dataptr_to_db(mp, ctx->pos) > mp->m_dirdatablk)
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+ return 0;
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+
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+ /*
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+ * Precalculate offsets for . and .. as we will always need them.
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+ *
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+ * XXX(hch): the second argument is sometimes 0 and sometimes
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+ * mp->m_dirdatablk.
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+ */
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+ dot_offset = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
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+ XFS_DIR3_DATA_DOT_OFFSET(mp));
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+ dotdot_offset = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
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+ XFS_DIR3_DATA_DOTDOT_OFFSET(mp));
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+
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+ /*
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+ * Put . entry unless we're starting past it.
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+ */
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+ if (ctx->pos <= dot_offset) {
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+ ctx->pos = dot_offset & 0x7fffffff;
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+ if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR))
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+ return 0;
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+ }
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+
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+ /*
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+ * Put .. entry unless we're starting past it.
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+ */
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+ if (ctx->pos <= dotdot_offset) {
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+ ino = xfs_dir2_sf_get_parent_ino(sfp);
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+ ctx->pos = dotdot_offset & 0x7fffffff;
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+ if (!dir_emit(ctx, "..", 2, ino, DT_DIR))
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+ return 0;
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+ }
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+
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+ /*
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+ * Loop while there are more entries and put'ing works.
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+ */
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+ sfep = xfs_dir2_sf_firstentry(sfp);
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+ for (i = 0; i < sfp->count; i++) {
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+ off = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
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+ xfs_dir2_sf_get_offset(sfep));
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+
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+ if (ctx->pos > off) {
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+ sfep = xfs_dir2_sf_nextentry(sfp, sfep);
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+ continue;
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+ }
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+
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+ ino = xfs_dir2_sfe_get_ino(sfp, sfep);
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+ ctx->pos = off & 0x7fffffff;
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+ if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen,
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+ ino, DT_UNKNOWN))
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+ return 0;
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+ sfep = xfs_dir2_sf_nextentry(sfp, sfep);
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+ }
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+
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+ ctx->pos = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk + 1, 0) &
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+ 0x7fffffff;
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+ return 0;
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+}
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+
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+/*
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+ * Readdir for block directories.
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+ */
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+STATIC int
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+xfs_dir2_block_getdents(
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+ xfs_inode_t *dp, /* incore inode */
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+ struct dir_context *ctx)
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+{
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+ xfs_dir2_data_hdr_t *hdr; /* block header */
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+ struct xfs_buf *bp; /* buffer for block */
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+ xfs_dir2_block_tail_t *btp; /* block tail */
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+ xfs_dir2_data_entry_t *dep; /* block data entry */
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+ xfs_dir2_data_unused_t *dup; /* block unused entry */
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+ char *endptr; /* end of the data entries */
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+ int error; /* error return value */
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+ xfs_mount_t *mp; /* filesystem mount point */
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+ char *ptr; /* current data entry */
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+ int wantoff; /* starting block offset */
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+ xfs_off_t cook;
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+
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+ mp = dp->i_mount;
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+ /*
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+ * If the block number in the offset is out of range, we're done.
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+ */
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+ if (xfs_dir2_dataptr_to_db(mp, ctx->pos) > mp->m_dirdatablk)
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+ return 0;
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+
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+ error = xfs_dir3_block_read(NULL, dp, &bp);
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+ if (error)
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+ return error;
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+
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+ /*
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+ * Extract the byte offset we start at from the seek pointer.
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+ * We'll skip entries before this.
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+ */
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+ wantoff = xfs_dir2_dataptr_to_off(mp, ctx->pos);
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+ hdr = bp->b_addr;
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+ xfs_dir3_data_check(dp, bp);
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+ /*
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+ * Set up values for the loop.
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+ */
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+ btp = xfs_dir2_block_tail_p(mp, hdr);
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+ ptr = (char *)xfs_dir3_data_entry_p(hdr);
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+ endptr = (char *)xfs_dir2_block_leaf_p(btp);
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+
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+ /*
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+ * Loop over the data portion of the block.
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+ * Each object is a real entry (dep) or an unused one (dup).
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+ */
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+ while (ptr < endptr) {
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+ dup = (xfs_dir2_data_unused_t *)ptr;
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+ /*
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+ * Unused, skip it.
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+ */
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+ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
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+ ptr += be16_to_cpu(dup->length);
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+ continue;
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+ }
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+
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+ dep = (xfs_dir2_data_entry_t *)ptr;
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+
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+ /*
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+ * Bump pointer for the next iteration.
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+ */
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+ ptr += xfs_dir2_data_entsize(dep->namelen);
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+ /*
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+ * The entry is before the desired starting point, skip it.
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+ */
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+ if ((char *)dep - (char *)hdr < wantoff)
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+ continue;
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+
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+ cook = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
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+ (char *)dep - (char *)hdr);
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+
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+ ctx->pos = cook & 0x7fffffff;
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+ /*
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+ * If it didn't fit, set the final offset to here & return.
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+ */
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+ if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
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+ be64_to_cpu(dep->inumber), DT_UNKNOWN)) {
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+ xfs_trans_brelse(NULL, bp);
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+ return 0;
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+ }
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+ }
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+
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+ /*
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+ * Reached the end of the block.
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+ * Set the offset to a non-existent block 1 and return.
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+ */
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+ ctx->pos = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk + 1, 0) &
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+ 0x7fffffff;
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+ xfs_trans_brelse(NULL, bp);
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+ return 0;
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+}
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+
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+struct xfs_dir2_leaf_map_info {
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+ xfs_extlen_t map_blocks; /* number of fsbs in map */
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+ xfs_dablk_t map_off; /* last mapped file offset */
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+ int map_size; /* total entries in *map */
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+ int map_valid; /* valid entries in *map */
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+ int nmap; /* mappings to ask xfs_bmapi */
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+ xfs_dir2_db_t curdb; /* db for current block */
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+ int ra_current; /* number of read-ahead blks */
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+ int ra_index; /* *map index for read-ahead */
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+ int ra_offset; /* map entry offset for ra */
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+ int ra_want; /* readahead count wanted */
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+ struct xfs_bmbt_irec map[]; /* map vector for blocks */
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+};
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+
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+STATIC int
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+xfs_dir2_leaf_readbuf(
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+ struct xfs_inode *dp,
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+ size_t bufsize,
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+ struct xfs_dir2_leaf_map_info *mip,
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+ xfs_dir2_off_t *curoff,
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+ struct xfs_buf **bpp)
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+{
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+ struct xfs_mount *mp = dp->i_mount;
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+ struct xfs_buf *bp = *bpp;
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+ struct xfs_bmbt_irec *map = mip->map;
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+ struct blk_plug plug;
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+ int error = 0;
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+ int length;
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+ int i;
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+ int j;
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+
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+ /*
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+ * If we have a buffer, we need to release it and
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+ * take it out of the mapping.
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+ */
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+
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+ if (bp) {
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+ xfs_trans_brelse(NULL, bp);
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+ bp = NULL;
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+ mip->map_blocks -= mp->m_dirblkfsbs;
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+ /*
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+ * Loop to get rid of the extents for the
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+ * directory block.
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+ */
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+ for (i = mp->m_dirblkfsbs; i > 0; ) {
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+ j = min_t(int, map->br_blockcount, i);
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+ map->br_blockcount -= j;
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+ map->br_startblock += j;
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+ map->br_startoff += j;
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+ /*
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+ * If mapping is done, pitch it from
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+ * the table.
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+ */
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+ if (!map->br_blockcount && --mip->map_valid)
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+ memmove(&map[0], &map[1],
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+ sizeof(map[0]) * mip->map_valid);
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+ i -= j;
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+ }
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+ }
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+
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+ /*
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+ * Recalculate the readahead blocks wanted.
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+ */
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+ mip->ra_want = howmany(bufsize + mp->m_dirblksize,
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+ mp->m_sb.sb_blocksize) - 1;
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+ ASSERT(mip->ra_want >= 0);
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+
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+ /*
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+ * If we don't have as many as we want, and we haven't
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+ * run out of data blocks, get some more mappings.
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+ */
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+ if (1 + mip->ra_want > mip->map_blocks &&
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+ mip->map_off < xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
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+ /*
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+ * Get more bmaps, fill in after the ones
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+ * we already have in the table.
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+ */
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+ mip->nmap = mip->map_size - mip->map_valid;
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+ error = xfs_bmapi_read(dp, mip->map_off,
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+ xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET) -
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+ mip->map_off,
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+ &map[mip->map_valid], &mip->nmap, 0);
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+
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+ /*
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+ * Don't know if we should ignore this or try to return an
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+ * error. The trouble with returning errors is that readdir
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+ * will just stop without actually passing the error through.
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+ */
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+ if (error)
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+ goto out; /* XXX */
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+
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+ /*
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+ * If we got all the mappings we asked for, set the final map
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+ * offset based on the last bmap value received. Otherwise,
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+ * we've reached the end.
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+ */
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+ if (mip->nmap == mip->map_size - mip->map_valid) {
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+ i = mip->map_valid + mip->nmap - 1;
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+ mip->map_off = map[i].br_startoff + map[i].br_blockcount;
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+ } else
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+ mip->map_off = xfs_dir2_byte_to_da(mp,
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+ XFS_DIR2_LEAF_OFFSET);
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+
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+ /*
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+ * Look for holes in the mapping, and eliminate them. Count up
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+ * the valid blocks.
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+ */
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+ for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
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+ if (map[i].br_startblock == HOLESTARTBLOCK) {
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+ mip->nmap--;
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+ length = mip->map_valid + mip->nmap - i;
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+ if (length)
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+ memmove(&map[i], &map[i + 1],
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+ sizeof(map[i]) * length);
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+ } else {
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+ mip->map_blocks += map[i].br_blockcount;
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+ i++;
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+ }
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+ }
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+ mip->map_valid += mip->nmap;
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+ }
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+
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+ /*
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+ * No valid mappings, so no more data blocks.
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+ */
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+ if (!mip->map_valid) {
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+ *curoff = xfs_dir2_da_to_byte(mp, mip->map_off);
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+ goto out;
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+ }
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+
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+ /*
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+ * Read the directory block starting at the first mapping.
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+ */
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+ mip->curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
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+ error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
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+ map->br_blockcount >= mp->m_dirblkfsbs ?
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+ XFS_FSB_TO_DADDR(mp, map->br_startblock) : -1, &bp);
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+
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+ /*
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+ * Should just skip over the data block instead of giving up.
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+ */
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+ if (error)
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+ goto out; /* XXX */
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+
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+ /*
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+ * Adjust the current amount of read-ahead: we just read a block that
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+ * was previously ra.
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+ */
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+ if (mip->ra_current)
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+ mip->ra_current -= mp->m_dirblkfsbs;
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+
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+ /*
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+ * Do we need more readahead?
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+ */
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+ blk_start_plug(&plug);
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+ for (mip->ra_index = mip->ra_offset = i = 0;
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+ mip->ra_want > mip->ra_current && i < mip->map_blocks;
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+ i += mp->m_dirblkfsbs) {
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|
|
+ ASSERT(mip->ra_index < mip->map_valid);
|
|
|
+ /*
|
|
|
+ * Read-ahead a contiguous directory block.
|
|
|
+ */
|
|
|
+ if (i > mip->ra_current &&
|
|
|
+ map[mip->ra_index].br_blockcount >= mp->m_dirblkfsbs) {
|
|
|
+ xfs_dir3_data_readahead(NULL, dp,
|
|
|
+ map[mip->ra_index].br_startoff + mip->ra_offset,
|
|
|
+ XFS_FSB_TO_DADDR(mp,
|
|
|
+ map[mip->ra_index].br_startblock +
|
|
|
+ mip->ra_offset));
|
|
|
+ mip->ra_current = i;
|
|
|
+ }
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Read-ahead a non-contiguous directory block. This doesn't
|
|
|
+ * use our mapping, but this is a very rare case.
|
|
|
+ */
|
|
|
+ else if (i > mip->ra_current) {
|
|
|
+ xfs_dir3_data_readahead(NULL, dp,
|
|
|
+ map[mip->ra_index].br_startoff +
|
|
|
+ mip->ra_offset, -1);
|
|
|
+ mip->ra_current = i;
|
|
|
+ }
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Advance offset through the mapping table.
|
|
|
+ */
|
|
|
+ for (j = 0; j < mp->m_dirblkfsbs; j++) {
|
|
|
+ /*
|
|
|
+ * The rest of this extent but not more than a dir
|
|
|
+ * block.
|
|
|
+ */
|
|
|
+ length = min_t(int, mp->m_dirblkfsbs,
|
|
|
+ map[mip->ra_index].br_blockcount -
|
|
|
+ mip->ra_offset);
|
|
|
+ j += length;
|
|
|
+ mip->ra_offset += length;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Advance to the next mapping if this one is used up.
|
|
|
+ */
|
|
|
+ if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
|
|
|
+ mip->ra_offset = 0;
|
|
|
+ mip->ra_index++;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+ blk_finish_plug(&plug);
|
|
|
+
|
|
|
+out:
|
|
|
+ *bpp = bp;
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * Getdents (readdir) for leaf and node directories.
|
|
|
+ * This reads the data blocks only, so is the same for both forms.
|
|
|
+ */
|
|
|
+STATIC int
|
|
|
+xfs_dir2_leaf_getdents(
|
|
|
+ xfs_inode_t *dp, /* incore directory inode */
|
|
|
+ struct dir_context *ctx,
|
|
|
+ size_t bufsize)
|
|
|
+{
|
|
|
+ struct xfs_buf *bp = NULL; /* data block buffer */
|
|
|
+ xfs_dir2_data_hdr_t *hdr; /* data block header */
|
|
|
+ xfs_dir2_data_entry_t *dep; /* data entry */
|
|
|
+ xfs_dir2_data_unused_t *dup; /* unused entry */
|
|
|
+ int error = 0; /* error return value */
|
|
|
+ int length; /* temporary length value */
|
|
|
+ xfs_mount_t *mp; /* filesystem mount point */
|
|
|
+ int byteoff; /* offset in current block */
|
|
|
+ xfs_dir2_off_t curoff; /* current overall offset */
|
|
|
+ xfs_dir2_off_t newoff; /* new curoff after new blk */
|
|
|
+ char *ptr = NULL; /* pointer to current data */
|
|
|
+ struct xfs_dir2_leaf_map_info *map_info;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * If the offset is at or past the largest allowed value,
|
|
|
+ * give up right away.
|
|
|
+ */
|
|
|
+ if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ mp = dp->i_mount;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Set up to bmap a number of blocks based on the caller's
|
|
|
+ * buffer size, the directory block size, and the filesystem
|
|
|
+ * block size.
|
|
|
+ */
|
|
|
+ length = howmany(bufsize + mp->m_dirblksize,
|
|
|
+ mp->m_sb.sb_blocksize);
|
|
|
+ map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
|
|
|
+ (length * sizeof(struct xfs_bmbt_irec)),
|
|
|
+ KM_SLEEP | KM_NOFS);
|
|
|
+ map_info->map_size = length;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Inside the loop we keep the main offset value as a byte offset
|
|
|
+ * in the directory file.
|
|
|
+ */
|
|
|
+ curoff = xfs_dir2_dataptr_to_byte(mp, ctx->pos);
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Force this conversion through db so we truncate the offset
|
|
|
+ * down to get the start of the data block.
|
|
|
+ */
|
|
|
+ map_info->map_off = xfs_dir2_db_to_da(mp,
|
|
|
+ xfs_dir2_byte_to_db(mp, curoff));
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Loop over directory entries until we reach the end offset.
|
|
|
+ * Get more blocks and readahead as necessary.
|
|
|
+ */
|
|
|
+ while (curoff < XFS_DIR2_LEAF_OFFSET) {
|
|
|
+ /*
|
|
|
+ * If we have no buffer, or we're off the end of the
|
|
|
+ * current buffer, need to get another one.
|
|
|
+ */
|
|
|
+ if (!bp || ptr >= (char *)bp->b_addr + mp->m_dirblksize) {
|
|
|
+
|
|
|
+ error = xfs_dir2_leaf_readbuf(dp, bufsize, map_info,
|
|
|
+ &curoff, &bp);
|
|
|
+ if (error || !map_info->map_valid)
|
|
|
+ break;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Having done a read, we need to set a new offset.
|
|
|
+ */
|
|
|
+ newoff = xfs_dir2_db_off_to_byte(mp, map_info->curdb, 0);
|
|
|
+ /*
|
|
|
+ * Start of the current block.
|
|
|
+ */
|
|
|
+ if (curoff < newoff)
|
|
|
+ curoff = newoff;
|
|
|
+ /*
|
|
|
+ * Make sure we're in the right block.
|
|
|
+ */
|
|
|
+ else if (curoff > newoff)
|
|
|
+ ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
|
|
|
+ map_info->curdb);
|
|
|
+ hdr = bp->b_addr;
|
|
|
+ xfs_dir3_data_check(dp, bp);
|
|
|
+ /*
|
|
|
+ * Find our position in the block.
|
|
|
+ */
|
|
|
+ ptr = (char *)xfs_dir3_data_entry_p(hdr);
|
|
|
+ byteoff = xfs_dir2_byte_to_off(mp, curoff);
|
|
|
+ /*
|
|
|
+ * Skip past the header.
|
|
|
+ */
|
|
|
+ if (byteoff == 0)
|
|
|
+ curoff += xfs_dir3_data_entry_offset(hdr);
|
|
|
+ /*
|
|
|
+ * Skip past entries until we reach our offset.
|
|
|
+ */
|
|
|
+ else {
|
|
|
+ while ((char *)ptr - (char *)hdr < byteoff) {
|
|
|
+ dup = (xfs_dir2_data_unused_t *)ptr;
|
|
|
+
|
|
|
+ if (be16_to_cpu(dup->freetag)
|
|
|
+ == XFS_DIR2_DATA_FREE_TAG) {
|
|
|
+
|
|
|
+ length = be16_to_cpu(dup->length);
|
|
|
+ ptr += length;
|
|
|
+ continue;
|
|
|
+ }
|
|
|
+ dep = (xfs_dir2_data_entry_t *)ptr;
|
|
|
+ length =
|
|
|
+ xfs_dir2_data_entsize(dep->namelen);
|
|
|
+ ptr += length;
|
|
|
+ }
|
|
|
+ /*
|
|
|
+ * Now set our real offset.
|
|
|
+ */
|
|
|
+ curoff =
|
|
|
+ xfs_dir2_db_off_to_byte(mp,
|
|
|
+ xfs_dir2_byte_to_db(mp, curoff),
|
|
|
+ (char *)ptr - (char *)hdr);
|
|
|
+ if (ptr >= (char *)hdr + mp->m_dirblksize) {
|
|
|
+ continue;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+ /*
|
|
|
+ * We have a pointer to an entry.
|
|
|
+ * Is it a live one?
|
|
|
+ */
|
|
|
+ dup = (xfs_dir2_data_unused_t *)ptr;
|
|
|
+ /*
|
|
|
+ * No, it's unused, skip over it.
|
|
|
+ */
|
|
|
+ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
|
|
|
+ length = be16_to_cpu(dup->length);
|
|
|
+ ptr += length;
|
|
|
+ curoff += length;
|
|
|
+ continue;
|
|
|
+ }
|
|
|
+
|
|
|
+ dep = (xfs_dir2_data_entry_t *)ptr;
|
|
|
+ length = xfs_dir2_data_entsize(dep->namelen);
|
|
|
+
|
|
|
+ ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
|
|
|
+ if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
|
|
|
+ be64_to_cpu(dep->inumber), DT_UNKNOWN))
|
|
|
+ break;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Advance to next entry in the block.
|
|
|
+ */
|
|
|
+ ptr += length;
|
|
|
+ curoff += length;
|
|
|
+ /* bufsize may have just been a guess; don't go negative */
|
|
|
+ bufsize = bufsize > length ? bufsize - length : 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ /*
|
|
|
+ * All done. Set output offset value to current offset.
|
|
|
+ */
|
|
|
+ if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
|
|
|
+ ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
|
|
|
+ else
|
|
|
+ ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
|
|
|
+ kmem_free(map_info);
|
|
|
+ if (bp)
|
|
|
+ xfs_trans_brelse(NULL, bp);
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * Read a directory.
|
|
|
+ */
|
|
|
+int
|
|
|
+xfs_readdir(
|
|
|
+ xfs_inode_t *dp,
|
|
|
+ struct dir_context *ctx,
|
|
|
+ size_t bufsize)
|
|
|
+{
|
|
|
+ int rval; /* return value */
|
|
|
+ int v; /* type-checking value */
|
|
|
+
|
|
|
+ trace_xfs_readdir(dp);
|
|
|
+
|
|
|
+ if (XFS_FORCED_SHUTDOWN(dp->i_mount))
|
|
|
+ return XFS_ERROR(EIO);
|
|
|
+
|
|
|
+ ASSERT(S_ISDIR(dp->i_d.di_mode));
|
|
|
+ XFS_STATS_INC(xs_dir_getdents);
|
|
|
+
|
|
|
+ if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
|
|
|
+ rval = xfs_dir2_sf_getdents(dp, ctx);
|
|
|
+ else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
|
|
|
+ ;
|
|
|
+ else if (v)
|
|
|
+ rval = xfs_dir2_block_getdents(dp, ctx);
|
|
|
+ else
|
|
|
+ rval = xfs_dir2_leaf_getdents(dp, ctx, bufsize);
|
|
|
+ return rval;
|
|
|
+}
|
Dave Chinner