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![Artem Bityutskiy](/assets/img/avatar_default.png)
This is a new flash file system. See http://www.linux-mtd.infradead.org/doc/ubifs.html Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
773 lines
21 KiB
C
773 lines
21 KiB
C
/*
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* This file is part of UBIFS.
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*
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* Copyright (C) 2006-2008 Nokia Corporation.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 51
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* Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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* Authors: Adrian Hunter
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* Artem Bityutskiy (Битюцкий Артём)
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*/
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/*
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* This file implements garbage collection. The procedure for garbage collection
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* is different depending on whether a LEB as an index LEB (contains index
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* nodes) or not. For non-index LEBs, garbage collection finds a LEB which
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* contains a lot of dirty space (obsolete nodes), and copies the non-obsolete
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* nodes to the journal, at which point the garbage-collected LEB is free to be
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* reused. For index LEBs, garbage collection marks the non-obsolete index nodes
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* dirty in the TNC, and after the next commit, the garbage-collected LEB is
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* to be reused. Garbage collection will cause the number of dirty index nodes
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* to grow, however sufficient space is reserved for the index to ensure the
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* commit will never run out of space.
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*/
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#include <linux/pagemap.h>
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#include "ubifs.h"
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/*
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* GC tries to optimize the way it fit nodes to available space, and it sorts
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* nodes a little. The below constants are watermarks which define "large",
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* "medium", and "small" nodes.
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*/
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#define MEDIUM_NODE_WM (UBIFS_BLOCK_SIZE / 4)
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#define SMALL_NODE_WM UBIFS_MAX_DENT_NODE_SZ
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/*
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* GC may need to move more then one LEB to make progress. The below constants
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* define "soft" and "hard" limits on the number of LEBs the garbage collector
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* may move.
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*/
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#define SOFT_LEBS_LIMIT 4
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#define HARD_LEBS_LIMIT 32
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/**
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* switch_gc_head - switch the garbage collection journal head.
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* @c: UBIFS file-system description object
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* @buf: buffer to write
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* @len: length of the buffer to write
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* @lnum: LEB number written is returned here
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* @offs: offset written is returned here
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*
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* This function switch the GC head to the next LEB which is reserved in
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* @c->gc_lnum. Returns %0 in case of success, %-EAGAIN if commit is required,
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* and other negative error code in case of failures.
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*/
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static int switch_gc_head(struct ubifs_info *c)
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{
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int err, gc_lnum = c->gc_lnum;
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struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
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ubifs_assert(gc_lnum != -1);
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dbg_gc("switch GC head from LEB %d:%d to LEB %d (waste %d bytes)",
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wbuf->lnum, wbuf->offs + wbuf->used, gc_lnum,
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c->leb_size - wbuf->offs - wbuf->used);
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err = ubifs_wbuf_sync_nolock(wbuf);
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if (err)
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return err;
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/*
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* The GC write-buffer was synchronized, we may safely unmap
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* 'c->gc_lnum'.
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*/
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err = ubifs_leb_unmap(c, gc_lnum);
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if (err)
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return err;
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err = ubifs_add_bud_to_log(c, GCHD, gc_lnum, 0);
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if (err)
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return err;
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c->gc_lnum = -1;
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err = ubifs_wbuf_seek_nolock(wbuf, gc_lnum, 0, UBI_LONGTERM);
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return err;
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}
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/**
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* move_nodes - move nodes.
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* @c: UBIFS file-system description object
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* @sleb: describes nodes to move
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*
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* This function moves valid nodes from data LEB described by @sleb to the GC
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* journal head. The obsolete nodes are dropped.
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*
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* When moving nodes we have to deal with classical bin-packing problem: the
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* space in the current GC journal head LEB and in @c->gc_lnum are the "bins",
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* where the nodes in the @sleb->nodes list are the elements which should be
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* fit optimally to the bins. This function uses the "first fit decreasing"
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* strategy, although it does not really sort the nodes but just split them on
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* 3 classes - large, medium, and small, so they are roughly sorted.
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*
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* This function returns zero in case of success, %-EAGAIN if commit is
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* required, and other negative error codes in case of other failures.
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*/
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static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
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{
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struct ubifs_scan_node *snod, *tmp;
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struct list_head large, medium, small;
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struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
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int avail, err, min = INT_MAX;
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INIT_LIST_HEAD(&large);
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INIT_LIST_HEAD(&medium);
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INIT_LIST_HEAD(&small);
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list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) {
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struct list_head *lst;
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ubifs_assert(snod->type != UBIFS_IDX_NODE);
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ubifs_assert(snod->type != UBIFS_REF_NODE);
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ubifs_assert(snod->type != UBIFS_CS_NODE);
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err = ubifs_tnc_has_node(c, &snod->key, 0, sleb->lnum,
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snod->offs, 0);
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if (err < 0)
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goto out;
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lst = &snod->list;
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list_del(lst);
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if (!err) {
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/* The node is obsolete, remove it from the list */
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kfree(snod);
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continue;
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}
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/*
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* Sort the list of nodes so that large nodes go first, and
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* small nodes go last.
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*/
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if (snod->len > MEDIUM_NODE_WM)
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list_add(lst, &large);
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else if (snod->len > SMALL_NODE_WM)
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list_add(lst, &medium);
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else
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list_add(lst, &small);
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/* And find the smallest node */
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if (snod->len < min)
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min = snod->len;
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}
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/*
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* Join the tree lists so that we'd have one roughly sorted list
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* ('large' will be the head of the joined list).
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*/
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list_splice(&medium, large.prev);
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list_splice(&small, large.prev);
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if (wbuf->lnum == -1) {
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/*
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* The GC journal head is not set, because it is the first GC
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* invocation since mount.
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*/
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err = switch_gc_head(c);
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if (err)
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goto out;
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}
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/* Write nodes to their new location. Use the first-fit strategy */
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while (1) {
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avail = c->leb_size - wbuf->offs - wbuf->used;
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list_for_each_entry_safe(snod, tmp, &large, list) {
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int new_lnum, new_offs;
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if (avail < min)
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break;
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if (snod->len > avail)
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/* This node does not fit */
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continue;
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cond_resched();
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new_lnum = wbuf->lnum;
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new_offs = wbuf->offs + wbuf->used;
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err = ubifs_wbuf_write_nolock(wbuf, snod->node,
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snod->len);
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if (err)
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goto out;
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err = ubifs_tnc_replace(c, &snod->key, sleb->lnum,
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snod->offs, new_lnum, new_offs,
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snod->len);
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if (err)
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goto out;
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avail = c->leb_size - wbuf->offs - wbuf->used;
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list_del(&snod->list);
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kfree(snod);
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}
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if (list_empty(&large))
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break;
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/*
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* Waste the rest of the space in the LEB and switch to the
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* next LEB.
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*/
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err = switch_gc_head(c);
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if (err)
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goto out;
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}
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return 0;
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out:
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list_for_each_entry_safe(snod, tmp, &large, list) {
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list_del(&snod->list);
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kfree(snod);
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}
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return err;
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}
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/**
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* gc_sync_wbufs - sync write-buffers for GC.
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* @c: UBIFS file-system description object
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*
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* We must guarantee that obsoleting nodes are on flash. Unfortunately they may
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* be in a write-buffer instead. That is, a node could be written to a
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* write-buffer, obsoleting another node in a LEB that is GC'd. If that LEB is
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* erased before the write-buffer is sync'd and then there is an unclean
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* unmount, then an existing node is lost. To avoid this, we sync all
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* write-buffers.
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*
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* This function returns %0 on success or a negative error code on failure.
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*/
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static int gc_sync_wbufs(struct ubifs_info *c)
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{
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int err, i;
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for (i = 0; i < c->jhead_cnt; i++) {
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if (i == GCHD)
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continue;
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err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
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if (err)
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return err;
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}
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return 0;
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}
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/**
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* ubifs_garbage_collect_leb - garbage-collect a logical eraseblock.
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* @c: UBIFS file-system description object
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* @lp: describes the LEB to garbage collect
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*
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* This function garbage-collects an LEB and returns one of the @LEB_FREED,
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* @LEB_RETAINED, etc positive codes in case of success, %-EAGAIN if commit is
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* required, and other negative error codes in case of failures.
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*/
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int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
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{
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struct ubifs_scan_leb *sleb;
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struct ubifs_scan_node *snod;
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struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
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int err = 0, lnum = lp->lnum;
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ubifs_assert(c->gc_lnum != -1 || wbuf->offs + wbuf->used == 0 ||
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c->need_recovery);
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ubifs_assert(c->gc_lnum != lnum);
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ubifs_assert(wbuf->lnum != lnum);
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/*
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* We scan the entire LEB even though we only really need to scan up to
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* (c->leb_size - lp->free).
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*/
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sleb = ubifs_scan(c, lnum, 0, c->sbuf);
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if (IS_ERR(sleb))
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return PTR_ERR(sleb);
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ubifs_assert(!list_empty(&sleb->nodes));
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snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
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if (snod->type == UBIFS_IDX_NODE) {
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struct ubifs_gced_idx_leb *idx_gc;
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dbg_gc("indexing LEB %d (free %d, dirty %d)",
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lnum, lp->free, lp->dirty);
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list_for_each_entry(snod, &sleb->nodes, list) {
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struct ubifs_idx_node *idx = snod->node;
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int level = le16_to_cpu(idx->level);
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ubifs_assert(snod->type == UBIFS_IDX_NODE);
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key_read(c, ubifs_idx_key(c, idx), &snod->key);
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err = ubifs_dirty_idx_node(c, &snod->key, level, lnum,
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snod->offs);
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if (err)
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goto out;
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}
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idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
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if (!idx_gc) {
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err = -ENOMEM;
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goto out;
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}
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idx_gc->lnum = lnum;
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idx_gc->unmap = 0;
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list_add(&idx_gc->list, &c->idx_gc);
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/*
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* Don't release the LEB until after the next commit, because
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* it may contain date which is needed for recovery. So
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* although we freed this LEB, it will become usable only after
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* the commit.
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*/
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err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0,
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LPROPS_INDEX, 1);
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if (err)
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goto out;
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err = LEB_FREED_IDX;
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} else {
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dbg_gc("data LEB %d (free %d, dirty %d)",
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lnum, lp->free, lp->dirty);
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err = move_nodes(c, sleb);
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if (err)
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goto out;
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err = gc_sync_wbufs(c);
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if (err)
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goto out;
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err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, 0, 0);
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if (err)
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goto out;
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if (c->gc_lnum == -1) {
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c->gc_lnum = lnum;
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err = LEB_RETAINED;
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} else {
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err = ubifs_wbuf_sync_nolock(wbuf);
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if (err)
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goto out;
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err = ubifs_leb_unmap(c, lnum);
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if (err)
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goto out;
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err = LEB_FREED;
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}
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}
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out:
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ubifs_scan_destroy(sleb);
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return err;
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}
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/**
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* ubifs_garbage_collect - UBIFS garbage collector.
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* @c: UBIFS file-system description object
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* @anyway: do GC even if there are free LEBs
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*
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* This function does out-of-place garbage collection. The return codes are:
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* o positive LEB number if the LEB has been freed and may be used;
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* o %-EAGAIN if the caller has to run commit;
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* o %-ENOSPC if GC failed to make any progress;
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* o other negative error codes in case of other errors.
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*
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* Garbage collector writes data to the journal when GC'ing data LEBs, and just
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* marking indexing nodes dirty when GC'ing indexing LEBs. Thus, at some point
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* commit may be required. But commit cannot be run from inside GC, because the
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* caller might be holding the commit lock, so %-EAGAIN is returned instead;
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* And this error code means that the caller has to run commit, and re-run GC
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* if there is still no free space.
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*
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* There are many reasons why this function may return %-EAGAIN:
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* o the log is full and there is no space to write an LEB reference for
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* @c->gc_lnum;
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* o the journal is too large and exceeds size limitations;
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* o GC moved indexing LEBs, but they can be used only after the commit;
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* o the shrinker fails to find clean znodes to free and requests the commit;
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* o etc.
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*
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* Note, if the file-system is close to be full, this function may return
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* %-EAGAIN infinitely, so the caller has to limit amount of re-invocations of
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* the function. E.g., this happens if the limits on the journal size are too
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* tough and GC writes too much to the journal before an LEB is freed. This
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* might also mean that the journal is too large, and the TNC becomes to big,
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* so that the shrinker is constantly called, finds not clean znodes to free,
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* and requests commit. Well, this may also happen if the journal is all right,
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* but another kernel process consumes too much memory. Anyway, infinite
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* %-EAGAIN may happen, but in some extreme/misconfiguration cases.
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*/
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int ubifs_garbage_collect(struct ubifs_info *c, int anyway)
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{
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int i, err, ret, min_space = c->dead_wm;
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struct ubifs_lprops lp;
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struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
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ubifs_assert_cmt_locked(c);
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if (ubifs_gc_should_commit(c))
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return -EAGAIN;
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mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
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if (c->ro_media) {
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ret = -EROFS;
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goto out_unlock;
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}
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/* We expect the write-buffer to be empty on entry */
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ubifs_assert(!wbuf->used);
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for (i = 0; ; i++) {
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int space_before = c->leb_size - wbuf->offs - wbuf->used;
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int space_after;
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cond_resched();
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/* Give the commit an opportunity to run */
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if (ubifs_gc_should_commit(c)) {
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ret = -EAGAIN;
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break;
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}
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if (i > SOFT_LEBS_LIMIT && !list_empty(&c->idx_gc)) {
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/*
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* We've done enough iterations. Indexing LEBs were
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* moved and will be available after the commit.
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*/
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dbg_gc("soft limit, some index LEBs GC'ed, -EAGAIN");
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ubifs_commit_required(c);
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ret = -EAGAIN;
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break;
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}
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if (i > HARD_LEBS_LIMIT) {
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/*
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* We've moved too many LEBs and have not made
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* progress, give up.
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*/
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dbg_gc("hard limit, -ENOSPC");
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ret = -ENOSPC;
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break;
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}
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/*
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* Empty and freeable LEBs can turn up while we waited for
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* the wbuf lock, or while we have been running GC. In that
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* case, we should just return one of those instead of
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* continuing to GC dirty LEBs. Hence we request
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* 'ubifs_find_dirty_leb()' to return an empty LEB if it can.
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*/
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ret = ubifs_find_dirty_leb(c, &lp, min_space, anyway ? 0 : 1);
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if (ret) {
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if (ret == -ENOSPC)
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dbg_gc("no more dirty LEBs");
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break;
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}
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dbg_gc("found LEB %d: free %d, dirty %d, sum %d "
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"(min. space %d)", lp.lnum, lp.free, lp.dirty,
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lp.free + lp.dirty, min_space);
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if (lp.free + lp.dirty == c->leb_size) {
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/* An empty LEB was returned */
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dbg_gc("LEB %d is free, return it", lp.lnum);
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/*
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* ubifs_find_dirty_leb() doesn't return freeable index
|
|
* LEBs.
|
|
*/
|
|
ubifs_assert(!(lp.flags & LPROPS_INDEX));
|
|
if (lp.free != c->leb_size) {
|
|
/*
|
|
* Write buffers must be sync'd before
|
|
* unmapping freeable LEBs, because one of them
|
|
* may contain data which obsoletes something
|
|
* in 'lp.pnum'.
|
|
*/
|
|
ret = gc_sync_wbufs(c);
|
|
if (ret)
|
|
goto out;
|
|
ret = ubifs_change_one_lp(c, lp.lnum,
|
|
c->leb_size, 0, 0, 0,
|
|
0);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
ret = ubifs_leb_unmap(c, lp.lnum);
|
|
if (ret)
|
|
goto out;
|
|
ret = lp.lnum;
|
|
break;
|
|
}
|
|
|
|
space_before = c->leb_size - wbuf->offs - wbuf->used;
|
|
if (wbuf->lnum == -1)
|
|
space_before = 0;
|
|
|
|
ret = ubifs_garbage_collect_leb(c, &lp);
|
|
if (ret < 0) {
|
|
if (ret == -EAGAIN || ret == -ENOSPC) {
|
|
/*
|
|
* These codes are not errors, so we have to
|
|
* return the LEB to lprops. But if the
|
|
* 'ubifs_return_leb()' function fails, its
|
|
* failure code is propagated to the caller
|
|
* instead of the original '-EAGAIN' or
|
|
* '-ENOSPC'.
|
|
*/
|
|
err = ubifs_return_leb(c, lp.lnum);
|
|
if (err)
|
|
ret = err;
|
|
break;
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
if (ret == LEB_FREED) {
|
|
/* An LEB has been freed and is ready for use */
|
|
dbg_gc("LEB %d freed, return", lp.lnum);
|
|
ret = lp.lnum;
|
|
break;
|
|
}
|
|
|
|
if (ret == LEB_FREED_IDX) {
|
|
/*
|
|
* This was an indexing LEB and it cannot be
|
|
* immediately used. And instead of requesting the
|
|
* commit straight away, we try to garbage collect some
|
|
* more.
|
|
*/
|
|
dbg_gc("indexing LEB %d freed, continue", lp.lnum);
|
|
continue;
|
|
}
|
|
|
|
ubifs_assert(ret == LEB_RETAINED);
|
|
space_after = c->leb_size - wbuf->offs - wbuf->used;
|
|
dbg_gc("LEB %d retained, freed %d bytes", lp.lnum,
|
|
space_after - space_before);
|
|
|
|
if (space_after > space_before) {
|
|
/* GC makes progress, keep working */
|
|
min_space >>= 1;
|
|
if (min_space < c->dead_wm)
|
|
min_space = c->dead_wm;
|
|
continue;
|
|
}
|
|
|
|
dbg_gc("did not make progress");
|
|
|
|
/*
|
|
* GC moved an LEB bud have not done any progress. This means
|
|
* that the previous GC head LEB contained too few free space
|
|
* and the LEB which was GC'ed contained only large nodes which
|
|
* did not fit that space.
|
|
*
|
|
* We can do 2 things:
|
|
* 1. pick another LEB in a hope it'll contain a small node
|
|
* which will fit the space we have at the end of current GC
|
|
* head LEB, but there is no guarantee, so we try this out
|
|
* unless we have already been working for too long;
|
|
* 2. request an LEB with more dirty space, which will force
|
|
* 'ubifs_find_dirty_leb()' to start scanning the lprops
|
|
* table, instead of just picking one from the heap
|
|
* (previously it already picked the dirtiest LEB).
|
|
*/
|
|
if (i < SOFT_LEBS_LIMIT) {
|
|
dbg_gc("try again");
|
|
continue;
|
|
}
|
|
|
|
min_space <<= 1;
|
|
if (min_space > c->dark_wm)
|
|
min_space = c->dark_wm;
|
|
dbg_gc("set min. space to %d", min_space);
|
|
}
|
|
|
|
if (ret == -ENOSPC && !list_empty(&c->idx_gc)) {
|
|
dbg_gc("no space, some index LEBs GC'ed, -EAGAIN");
|
|
ubifs_commit_required(c);
|
|
ret = -EAGAIN;
|
|
}
|
|
|
|
err = ubifs_wbuf_sync_nolock(wbuf);
|
|
if (!err)
|
|
err = ubifs_leb_unmap(c, c->gc_lnum);
|
|
if (err) {
|
|
ret = err;
|
|
goto out;
|
|
}
|
|
out_unlock:
|
|
mutex_unlock(&wbuf->io_mutex);
|
|
return ret;
|
|
|
|
out:
|
|
ubifs_assert(ret < 0);
|
|
ubifs_assert(ret != -ENOSPC && ret != -EAGAIN);
|
|
ubifs_ro_mode(c, ret);
|
|
ubifs_wbuf_sync_nolock(wbuf);
|
|
mutex_unlock(&wbuf->io_mutex);
|
|
ubifs_return_leb(c, lp.lnum);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* ubifs_gc_start_commit - garbage collection at start of commit.
|
|
* @c: UBIFS file-system description object
|
|
*
|
|
* If a LEB has only dirty and free space, then we may safely unmap it and make
|
|
* it free. Note, we cannot do this with indexing LEBs because dirty space may
|
|
* correspond index nodes that are required for recovery. In that case, the
|
|
* LEB cannot be unmapped until after the next commit.
|
|
*
|
|
* This function returns %0 upon success and a negative error code upon failure.
|
|
*/
|
|
int ubifs_gc_start_commit(struct ubifs_info *c)
|
|
{
|
|
struct ubifs_gced_idx_leb *idx_gc;
|
|
const struct ubifs_lprops *lp;
|
|
int err = 0, flags;
|
|
|
|
ubifs_get_lprops(c);
|
|
|
|
/*
|
|
* Unmap (non-index) freeable LEBs. Note that recovery requires that all
|
|
* wbufs are sync'd before this, which is done in 'do_commit()'.
|
|
*/
|
|
while (1) {
|
|
lp = ubifs_fast_find_freeable(c);
|
|
if (unlikely(IS_ERR(lp))) {
|
|
err = PTR_ERR(lp);
|
|
goto out;
|
|
}
|
|
if (!lp)
|
|
break;
|
|
ubifs_assert(!(lp->flags & LPROPS_TAKEN));
|
|
ubifs_assert(!(lp->flags & LPROPS_INDEX));
|
|
err = ubifs_leb_unmap(c, lp->lnum);
|
|
if (err)
|
|
goto out;
|
|
lp = ubifs_change_lp(c, lp, c->leb_size, 0, lp->flags, 0);
|
|
if (unlikely(IS_ERR(lp))) {
|
|
err = PTR_ERR(lp);
|
|
goto out;
|
|
}
|
|
ubifs_assert(!(lp->flags & LPROPS_TAKEN));
|
|
ubifs_assert(!(lp->flags & LPROPS_INDEX));
|
|
}
|
|
|
|
/* Mark GC'd index LEBs OK to unmap after this commit finishes */
|
|
list_for_each_entry(idx_gc, &c->idx_gc, list)
|
|
idx_gc->unmap = 1;
|
|
|
|
/* Record index freeable LEBs for unmapping after commit */
|
|
while (1) {
|
|
lp = ubifs_fast_find_frdi_idx(c);
|
|
if (unlikely(IS_ERR(lp))) {
|
|
err = PTR_ERR(lp);
|
|
goto out;
|
|
}
|
|
if (!lp)
|
|
break;
|
|
idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
|
|
if (!idx_gc) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
ubifs_assert(!(lp->flags & LPROPS_TAKEN));
|
|
ubifs_assert(lp->flags & LPROPS_INDEX);
|
|
/* Don't release the LEB until after the next commit */
|
|
flags = (lp->flags | LPROPS_TAKEN) ^ LPROPS_INDEX;
|
|
lp = ubifs_change_lp(c, lp, c->leb_size, 0, flags, 1);
|
|
if (unlikely(IS_ERR(lp))) {
|
|
err = PTR_ERR(lp);
|
|
kfree(idx_gc);
|
|
goto out;
|
|
}
|
|
ubifs_assert(lp->flags & LPROPS_TAKEN);
|
|
ubifs_assert(!(lp->flags & LPROPS_INDEX));
|
|
idx_gc->lnum = lp->lnum;
|
|
idx_gc->unmap = 1;
|
|
list_add(&idx_gc->list, &c->idx_gc);
|
|
}
|
|
out:
|
|
ubifs_release_lprops(c);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ubifs_gc_end_commit - garbage collection at end of commit.
|
|
* @c: UBIFS file-system description object
|
|
*
|
|
* This function completes out-of-place garbage collection of index LEBs.
|
|
*/
|
|
int ubifs_gc_end_commit(struct ubifs_info *c)
|
|
{
|
|
struct ubifs_gced_idx_leb *idx_gc, *tmp;
|
|
struct ubifs_wbuf *wbuf;
|
|
int err = 0;
|
|
|
|
wbuf = &c->jheads[GCHD].wbuf;
|
|
mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
|
|
list_for_each_entry_safe(idx_gc, tmp, &c->idx_gc, list)
|
|
if (idx_gc->unmap) {
|
|
dbg_gc("LEB %d", idx_gc->lnum);
|
|
err = ubifs_leb_unmap(c, idx_gc->lnum);
|
|
if (err)
|
|
goto out;
|
|
err = ubifs_change_one_lp(c, idx_gc->lnum, LPROPS_NC,
|
|
LPROPS_NC, 0, LPROPS_TAKEN, -1);
|
|
if (err)
|
|
goto out;
|
|
list_del(&idx_gc->list);
|
|
kfree(idx_gc);
|
|
}
|
|
out:
|
|
mutex_unlock(&wbuf->io_mutex);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ubifs_destroy_idx_gc - destroy idx_gc list.
|
|
* @c: UBIFS file-system description object
|
|
*
|
|
* This function destroys the idx_gc list. It is called when unmounting or
|
|
* remounting read-only so locks are not needed.
|
|
*/
|
|
void ubifs_destroy_idx_gc(struct ubifs_info *c)
|
|
{
|
|
while (!list_empty(&c->idx_gc)) {
|
|
struct ubifs_gced_idx_leb *idx_gc;
|
|
|
|
idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb,
|
|
list);
|
|
c->idx_gc_cnt -= 1;
|
|
list_del(&idx_gc->list);
|
|
kfree(idx_gc);
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* ubifs_get_idx_gc_leb - get a LEB from GC'd index LEB list.
|
|
* @c: UBIFS file-system description object
|
|
*
|
|
* Called during start commit so locks are not needed.
|
|
*/
|
|
int ubifs_get_idx_gc_leb(struct ubifs_info *c)
|
|
{
|
|
struct ubifs_gced_idx_leb *idx_gc;
|
|
int lnum;
|
|
|
|
if (list_empty(&c->idx_gc))
|
|
return -ENOSPC;
|
|
idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb, list);
|
|
lnum = idx_gc->lnum;
|
|
/* c->idx_gc_cnt is updated by the caller when lprops are updated */
|
|
list_del(&idx_gc->list);
|
|
kfree(idx_gc);
|
|
return lnum;
|
|
}
|