![Adrian Bunk](/assets/img/avatar_default.png)
This patch contains the following cleanups: - make needlessly global functions static - provide some debugging helper functions only for appropriate values of CONFIG_JFFS_FS_VERBOSE Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
799 lines
20 KiB
C
799 lines
20 KiB
C
/*
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* JFFS -- Journaling Flash File System, Linux implementation.
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*
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* Copyright (C) 1999, 2000 Axis Communications AB.
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*
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* Created by Finn Hakansson <finn@axis.com>.
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*
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* This is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* $Id: jffs_fm.c,v 1.27 2001/09/20 12:29:47 dwmw2 Exp $
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*
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* Ported to Linux 2.3.x and MTD:
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* Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB
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*
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*/
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/jffs.h>
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#include "jffs_fm.h"
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#if defined(JFFS_MARK_OBSOLETE) && JFFS_MARK_OBSOLETE
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static int jffs_mark_obsolete(struct jffs_fmcontrol *fmc, __u32 fm_offset);
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#endif
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static struct jffs_fm *jffs_alloc_fm(void);
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static void jffs_free_fm(struct jffs_fm *n);
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extern kmem_cache_t *fm_cache;
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extern kmem_cache_t *node_cache;
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#if CONFIG_JFFS_FS_VERBOSE > 0
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void
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jffs_print_fmcontrol(struct jffs_fmcontrol *fmc)
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{
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D(printk("struct jffs_fmcontrol: 0x%p\n", fmc));
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D(printk("{\n"));
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D(printk(" %u, /* flash_size */\n", fmc->flash_size));
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D(printk(" %u, /* used_size */\n", fmc->used_size));
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D(printk(" %u, /* dirty_size */\n", fmc->dirty_size));
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D(printk(" %u, /* free_size */\n", fmc->free_size));
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D(printk(" %u, /* sector_size */\n", fmc->sector_size));
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D(printk(" %u, /* min_free_size */\n", fmc->min_free_size));
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D(printk(" %u, /* max_chunk_size */\n", fmc->max_chunk_size));
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D(printk(" 0x%p, /* mtd */\n", fmc->mtd));
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D(printk(" 0x%p, /* head */ "
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"(head->offset = 0x%08x)\n",
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fmc->head, (fmc->head ? fmc->head->offset : 0)));
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D(printk(" 0x%p, /* tail */ "
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"(tail->offset + tail->size = 0x%08x)\n",
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fmc->tail,
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(fmc->tail ? fmc->tail->offset + fmc->tail->size : 0)));
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D(printk(" 0x%p, /* head_extra */\n", fmc->head_extra));
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D(printk(" 0x%p, /* tail_extra */\n", fmc->tail_extra));
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D(printk("}\n"));
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}
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#endif /* CONFIG_JFFS_FS_VERBOSE > 0 */
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#if CONFIG_JFFS_FS_VERBOSE > 2
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static void
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jffs_print_fm(struct jffs_fm *fm)
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{
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D(printk("struct jffs_fm: 0x%p\n", fm));
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D(printk("{\n"));
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D(printk(" 0x%08x, /* offset */\n", fm->offset));
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D(printk(" %u, /* size */\n", fm->size));
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D(printk(" 0x%p, /* prev */\n", fm->prev));
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D(printk(" 0x%p, /* next */\n", fm->next));
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D(printk(" 0x%p, /* nodes */\n", fm->nodes));
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D(printk("}\n"));
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}
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#endif /* CONFIG_JFFS_FS_VERBOSE > 2 */
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#if 0
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void
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jffs_print_node_ref(struct jffs_node_ref *ref)
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{
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D(printk("struct jffs_node_ref: 0x%p\n", ref));
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D(printk("{\n"));
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D(printk(" 0x%p, /* node */\n", ref->node));
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D(printk(" 0x%p, /* next */\n", ref->next));
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D(printk("}\n"));
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}
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#endif /* 0 */
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/* This function creates a new shiny flash memory control structure. */
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struct jffs_fmcontrol *
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jffs_build_begin(struct jffs_control *c, int unit)
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{
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struct jffs_fmcontrol *fmc;
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struct mtd_info *mtd;
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D3(printk("jffs_build_begin()\n"));
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fmc = (struct jffs_fmcontrol *)kmalloc(sizeof(struct jffs_fmcontrol),
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GFP_KERNEL);
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if (!fmc) {
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D(printk("jffs_build_begin(): Allocation of "
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"struct jffs_fmcontrol failed!\n"));
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return (struct jffs_fmcontrol *)0;
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}
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DJM(no_jffs_fmcontrol++);
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mtd = get_mtd_device(NULL, unit);
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if (!mtd) {
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kfree(fmc);
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DJM(no_jffs_fmcontrol--);
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return NULL;
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}
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/* Retrieve the size of the flash memory. */
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fmc->flash_size = mtd->size;
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D3(printk(" fmc->flash_size = %d bytes\n", fmc->flash_size));
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fmc->used_size = 0;
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fmc->dirty_size = 0;
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fmc->free_size = mtd->size;
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fmc->sector_size = mtd->erasesize;
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fmc->max_chunk_size = fmc->sector_size >> 1;
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/* min_free_size:
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1 sector, obviously.
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+ 1 x max_chunk_size, for when a nodes overlaps the end of a sector
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+ 1 x max_chunk_size again, which ought to be enough to handle
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the case where a rename causes a name to grow, and GC has
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to write out larger nodes than the ones it's obsoleting.
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We should fix it so it doesn't have to write the name
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_every_ time. Later.
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+ another 2 sectors because people keep getting GC stuck and
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we don't know why. This scares me - I want formal proof
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of correctness of whatever number we put here. dwmw2.
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*/
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fmc->min_free_size = fmc->sector_size << 2;
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fmc->mtd = mtd;
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fmc->c = c;
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fmc->head = NULL;
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fmc->tail = NULL;
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fmc->head_extra = NULL;
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fmc->tail_extra = NULL;
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init_MUTEX(&fmc->biglock);
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return fmc;
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}
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/* When the flash memory scan has completed, this function should be called
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before use of the control structure. */
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void
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jffs_build_end(struct jffs_fmcontrol *fmc)
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{
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D3(printk("jffs_build_end()\n"));
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if (!fmc->head) {
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fmc->head = fmc->head_extra;
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fmc->tail = fmc->tail_extra;
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}
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else if (fmc->head_extra) {
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fmc->tail_extra->next = fmc->head;
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fmc->head->prev = fmc->tail_extra;
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fmc->head = fmc->head_extra;
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}
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fmc->head_extra = NULL; /* These two instructions should be omitted. */
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fmc->tail_extra = NULL;
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D3(jffs_print_fmcontrol(fmc));
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}
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/* Call this function when the file system is unmounted. This function
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frees all memory used by this module. */
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void
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jffs_cleanup_fmcontrol(struct jffs_fmcontrol *fmc)
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{
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if (fmc) {
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struct jffs_fm *next = fmc->head;
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while (next) {
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struct jffs_fm *cur = next;
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next = next->next;
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jffs_free_fm(cur);
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}
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put_mtd_device(fmc->mtd);
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kfree(fmc);
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DJM(no_jffs_fmcontrol--);
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}
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}
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/* This function returns the size of the first chunk of free space on the
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flash memory. This function will return something nonzero if the flash
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memory contains any free space. */
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__u32
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jffs_free_size1(struct jffs_fmcontrol *fmc)
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{
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__u32 head;
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__u32 tail;
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__u32 end = fmc->flash_size;
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if (!fmc->head) {
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/* There is nothing on the flash. */
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return fmc->flash_size;
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}
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/* Compute the beginning and ending of the contents of the flash. */
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head = fmc->head->offset;
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tail = fmc->tail->offset + fmc->tail->size;
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if (tail == end) {
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tail = 0;
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}
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ASSERT(else if (tail > end) {
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printk(KERN_WARNING "jffs_free_size1(): tail > end\n");
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tail = 0;
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});
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if (head <= tail) {
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return end - tail;
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}
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else {
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return head - tail;
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}
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}
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/* This function will return something nonzero in case there are two free
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areas on the flash. Like this:
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+----------------+------------------+----------------+
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| FREE 1 | USED / DIRTY | FREE 2 |
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+----------------+------------------+----------------+
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fmc->head -----^
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fmc->tail ------------------------^
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The value returned, will be the size of the first empty area on the
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flash, in this case marked "FREE 1". */
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__u32
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jffs_free_size2(struct jffs_fmcontrol *fmc)
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{
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if (fmc->head) {
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__u32 head = fmc->head->offset;
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__u32 tail = fmc->tail->offset + fmc->tail->size;
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if (tail == fmc->flash_size) {
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tail = 0;
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}
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if (tail >= head) {
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return head;
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}
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}
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return 0;
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}
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/* Allocate a chunk of flash memory. If there is enough space on the
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device, a reference to the associated node is stored in the jffs_fm
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struct. */
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int
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jffs_fmalloc(struct jffs_fmcontrol *fmc, __u32 size, struct jffs_node *node,
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struct jffs_fm **result)
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{
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struct jffs_fm *fm;
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__u32 free_chunk_size1;
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__u32 free_chunk_size2;
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D2(printk("jffs_fmalloc(): fmc = 0x%p, size = %d, "
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"node = 0x%p\n", fmc, size, node));
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*result = NULL;
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if (!(fm = jffs_alloc_fm())) {
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D(printk("jffs_fmalloc(): kmalloc() failed! (fm)\n"));
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return -ENOMEM;
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}
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free_chunk_size1 = jffs_free_size1(fmc);
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free_chunk_size2 = jffs_free_size2(fmc);
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if (free_chunk_size1 + free_chunk_size2 != fmc->free_size) {
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printk(KERN_WARNING "Free size accounting screwed\n");
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printk(KERN_WARNING "free_chunk_size1 == 0x%x, free_chunk_size2 == 0x%x, fmc->free_size == 0x%x\n", free_chunk_size1, free_chunk_size2, fmc->free_size);
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}
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D3(printk("jffs_fmalloc(): free_chunk_size1 = %u, "
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"free_chunk_size2 = %u\n",
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free_chunk_size1, free_chunk_size2));
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if (size <= free_chunk_size1) {
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if (!(fm->nodes = (struct jffs_node_ref *)
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kmalloc(sizeof(struct jffs_node_ref),
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GFP_KERNEL))) {
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D(printk("jffs_fmalloc(): kmalloc() failed! "
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"(node_ref)\n"));
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jffs_free_fm(fm);
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return -ENOMEM;
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}
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DJM(no_jffs_node_ref++);
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fm->nodes->node = node;
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fm->nodes->next = NULL;
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if (fmc->tail) {
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fm->offset = fmc->tail->offset + fmc->tail->size;
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if (fm->offset == fmc->flash_size) {
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fm->offset = 0;
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}
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ASSERT(else if (fm->offset > fmc->flash_size) {
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printk(KERN_WARNING "jffs_fmalloc(): "
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"offset > flash_end\n");
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fm->offset = 0;
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});
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}
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else {
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/* There don't have to be files in the file
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system yet. */
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fm->offset = 0;
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}
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fm->size = size;
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fmc->free_size -= size;
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fmc->used_size += size;
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}
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else if (size > free_chunk_size2) {
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printk(KERN_WARNING "JFFS: Tried to allocate a too "
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"large flash memory chunk. (size = %u)\n", size);
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jffs_free_fm(fm);
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return -ENOSPC;
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}
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else {
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fm->offset = fmc->tail->offset + fmc->tail->size;
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fm->size = free_chunk_size1;
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fm->nodes = NULL;
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fmc->free_size -= fm->size;
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fmc->dirty_size += fm->size; /* Changed by simonk. This seemingly fixes a
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bug that caused infinite garbage collection.
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It previously set fmc->dirty_size to size (which is the
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size of the requested chunk).
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*/
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}
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fm->next = NULL;
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if (!fmc->head) {
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fm->prev = NULL;
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fmc->head = fm;
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fmc->tail = fm;
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}
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else {
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fm->prev = fmc->tail;
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fmc->tail->next = fm;
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fmc->tail = fm;
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}
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D3(jffs_print_fmcontrol(fmc));
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D3(jffs_print_fm(fm));
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*result = fm;
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return 0;
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}
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/* The on-flash space is not needed anymore by the passed node. Remove
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the reference to the node from the node list. If the data chunk in
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the flash memory isn't used by any more nodes anymore (fm->nodes == 0),
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then mark that chunk as dirty. */
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int
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jffs_fmfree(struct jffs_fmcontrol *fmc, struct jffs_fm *fm, struct jffs_node *node)
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{
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struct jffs_node_ref *ref;
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struct jffs_node_ref *prev;
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ASSERT(int del = 0);
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D2(printk("jffs_fmfree(): node->ino = %u, node->version = %u\n",
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node->ino, node->version));
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ASSERT(if (!fmc || !fm || !fm->nodes) {
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printk(KERN_ERR "jffs_fmfree(): fmc: 0x%p, fm: 0x%p, "
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"fm->nodes: 0x%p\n",
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fmc, fm, (fm ? fm->nodes : NULL));
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return -1;
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});
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/* Find the reference to the node that is going to be removed
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and remove it. */
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for (ref = fm->nodes, prev = NULL; ref; ref = ref->next) {
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if (ref->node == node) {
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if (prev) {
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prev->next = ref->next;
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}
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else {
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fm->nodes = ref->next;
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}
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kfree(ref);
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DJM(no_jffs_node_ref--);
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ASSERT(del = 1);
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break;
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}
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prev = ref;
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}
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/* If the data chunk in the flash memory isn't used anymore
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just mark it as obsolete. */
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if (!fm->nodes) {
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/* No node uses this chunk so let's remove it. */
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fmc->used_size -= fm->size;
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fmc->dirty_size += fm->size;
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#if defined(JFFS_MARK_OBSOLETE) && JFFS_MARK_OBSOLETE
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if (jffs_mark_obsolete(fmc, fm->offset) < 0) {
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D1(printk("jffs_fmfree(): Failed to mark an on-flash "
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"node obsolete!\n"));
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return -1;
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}
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#endif
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}
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ASSERT(if (!del) {
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printk(KERN_WARNING "***jffs_fmfree(): "
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"Didn't delete any node reference!\n");
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});
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return 0;
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}
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/* This allocation function is used during the initialization of
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the file system. */
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struct jffs_fm *
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jffs_fmalloced(struct jffs_fmcontrol *fmc, __u32 offset, __u32 size,
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struct jffs_node *node)
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{
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struct jffs_fm *fm;
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D3(printk("jffs_fmalloced()\n"));
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if (!(fm = jffs_alloc_fm())) {
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D(printk("jffs_fmalloced(0x%p, %u, %u, 0x%p): failed!\n",
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fmc, offset, size, node));
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return NULL;
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}
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fm->offset = offset;
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fm->size = size;
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fm->prev = NULL;
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fm->next = NULL;
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fm->nodes = NULL;
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if (node) {
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/* `node' exists and it should be associated with the
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jffs_fm structure `fm'. */
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if (!(fm->nodes = (struct jffs_node_ref *)
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kmalloc(sizeof(struct jffs_node_ref),
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GFP_KERNEL))) {
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D(printk("jffs_fmalloced(): !fm->nodes\n"));
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jffs_free_fm(fm);
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return NULL;
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}
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DJM(no_jffs_node_ref++);
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fm->nodes->node = node;
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fm->nodes->next = NULL;
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fmc->used_size += size;
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fmc->free_size -= size;
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}
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else {
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/* If there is no node, then this is just a chunk of dirt. */
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fmc->dirty_size += size;
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fmc->free_size -= size;
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}
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if (fmc->head_extra) {
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fm->prev = fmc->tail_extra;
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fmc->tail_extra->next = fm;
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fmc->tail_extra = fm;
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}
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else if (!fmc->head) {
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fmc->head = fm;
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fmc->tail = fm;
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}
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else if (fmc->tail->offset + fmc->tail->size < offset) {
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fmc->head_extra = fm;
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fmc->tail_extra = fm;
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}
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else {
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fm->prev = fmc->tail;
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fmc->tail->next = fm;
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fmc->tail = fm;
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}
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D3(jffs_print_fmcontrol(fmc));
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D3(jffs_print_fm(fm));
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return fm;
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}
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/* Add a new node to an already existing jffs_fm struct. */
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int
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jffs_add_node(struct jffs_node *node)
|
|
{
|
|
struct jffs_node_ref *ref;
|
|
|
|
D3(printk("jffs_add_node(): ino = %u\n", node->ino));
|
|
|
|
ref = (struct jffs_node_ref *)kmalloc(sizeof(struct jffs_node_ref),
|
|
GFP_KERNEL);
|
|
if (!ref)
|
|
return -ENOMEM;
|
|
|
|
DJM(no_jffs_node_ref++);
|
|
ref->node = node;
|
|
ref->next = node->fm->nodes;
|
|
node->fm->nodes = ref;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Free a part of some allocated space. */
|
|
void
|
|
jffs_fmfree_partly(struct jffs_fmcontrol *fmc, struct jffs_fm *fm, __u32 size)
|
|
{
|
|
D1(printk("***jffs_fmfree_partly(): fm = 0x%p, fm->nodes = 0x%p, "
|
|
"fm->nodes->node->ino = %u, size = %u\n",
|
|
fm, (fm ? fm->nodes : 0),
|
|
(!fm ? 0 : (!fm->nodes ? 0 : fm->nodes->node->ino)), size));
|
|
|
|
if (fm->nodes) {
|
|
kfree(fm->nodes);
|
|
DJM(no_jffs_node_ref--);
|
|
fm->nodes = NULL;
|
|
}
|
|
fmc->used_size -= fm->size;
|
|
if (fm == fmc->tail) {
|
|
fm->size -= size;
|
|
fmc->free_size += size;
|
|
}
|
|
fmc->dirty_size += fm->size;
|
|
}
|
|
|
|
|
|
/* Find the jffs_fm struct that contains the end of the data chunk that
|
|
begins at the logical beginning of the flash memory and spans `size'
|
|
bytes. If we want to erase a sector of the flash memory, we use this
|
|
function to find where the sector limit cuts a chunk of data. */
|
|
struct jffs_fm *
|
|
jffs_cut_node(struct jffs_fmcontrol *fmc, __u32 size)
|
|
{
|
|
struct jffs_fm *fm;
|
|
__u32 pos = 0;
|
|
|
|
if (size == 0) {
|
|
return NULL;
|
|
}
|
|
|
|
ASSERT(if (!fmc) {
|
|
printk(KERN_ERR "jffs_cut_node(): fmc == NULL\n");
|
|
return NULL;
|
|
});
|
|
|
|
fm = fmc->head;
|
|
|
|
while (fm) {
|
|
pos += fm->size;
|
|
if (pos < size) {
|
|
fm = fm->next;
|
|
}
|
|
else if (pos > size) {
|
|
break;
|
|
}
|
|
else {
|
|
fm = NULL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return fm;
|
|
}
|
|
|
|
|
|
/* Move the head of the fmc structures and delete the obsolete parts. */
|
|
void
|
|
jffs_sync_erase(struct jffs_fmcontrol *fmc, int erased_size)
|
|
{
|
|
struct jffs_fm *fm;
|
|
struct jffs_fm *del;
|
|
|
|
ASSERT(if (!fmc) {
|
|
printk(KERN_ERR "jffs_sync_erase(): fmc == NULL\n");
|
|
return;
|
|
});
|
|
|
|
fmc->dirty_size -= erased_size;
|
|
fmc->free_size += erased_size;
|
|
|
|
for (fm = fmc->head; fm && (erased_size > 0);) {
|
|
if (erased_size >= fm->size) {
|
|
erased_size -= fm->size;
|
|
del = fm;
|
|
fm = fm->next;
|
|
fm->prev = NULL;
|
|
fmc->head = fm;
|
|
jffs_free_fm(del);
|
|
}
|
|
else {
|
|
fm->size -= erased_size;
|
|
fm->offset += erased_size;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* Return the oldest used node in the flash memory. */
|
|
struct jffs_node *
|
|
jffs_get_oldest_node(struct jffs_fmcontrol *fmc)
|
|
{
|
|
struct jffs_fm *fm;
|
|
struct jffs_node_ref *nref;
|
|
struct jffs_node *node = NULL;
|
|
|
|
ASSERT(if (!fmc) {
|
|
printk(KERN_ERR "jffs_get_oldest_node(): fmc == NULL\n");
|
|
return NULL;
|
|
});
|
|
|
|
for (fm = fmc->head; fm && !fm->nodes; fm = fm->next);
|
|
|
|
if (!fm) {
|
|
return NULL;
|
|
}
|
|
|
|
/* The oldest node is the last one in the reference list. This list
|
|
shouldn't be too long; just one or perhaps two elements. */
|
|
for (nref = fm->nodes; nref; nref = nref->next) {
|
|
node = nref->node;
|
|
}
|
|
|
|
D2(printk("jffs_get_oldest_node(): ino = %u, version = %u\n",
|
|
(node ? node->ino : 0), (node ? node->version : 0)));
|
|
|
|
return node;
|
|
}
|
|
|
|
|
|
#if defined(JFFS_MARK_OBSOLETE) && JFFS_MARK_OBSOLETE
|
|
|
|
/* Mark an on-flash node as obsolete.
|
|
|
|
Note that this is just an optimization that isn't necessary for the
|
|
filesystem to work. */
|
|
|
|
static int
|
|
jffs_mark_obsolete(struct jffs_fmcontrol *fmc, __u32 fm_offset)
|
|
{
|
|
/* The `accurate_pos' holds the position of the accurate byte
|
|
in the jffs_raw_inode structure that we are going to mark
|
|
as obsolete. */
|
|
__u32 accurate_pos = fm_offset + JFFS_RAW_INODE_ACCURATE_OFFSET;
|
|
unsigned char zero = 0x00;
|
|
size_t len;
|
|
|
|
D3(printk("jffs_mark_obsolete(): accurate_pos = %u\n", accurate_pos));
|
|
ASSERT(if (!fmc) {
|
|
printk(KERN_ERR "jffs_mark_obsolete(): fmc == NULL\n");
|
|
return -1;
|
|
});
|
|
|
|
/* Write 0x00 to the raw inode's accurate member. Don't care
|
|
about the return value. */
|
|
MTD_WRITE(fmc->mtd, accurate_pos, 1, &len, &zero);
|
|
return 0;
|
|
}
|
|
|
|
#endif /* JFFS_MARK_OBSOLETE */
|
|
|
|
/* check if it's possible to erase the wanted range, and if not, return
|
|
* the range that IS erasable, or a negative error code.
|
|
*/
|
|
static long
|
|
jffs_flash_erasable_size(struct mtd_info *mtd, __u32 offset, __u32 size)
|
|
{
|
|
u_long ssize;
|
|
|
|
/* assume that sector size for a partition is constant even
|
|
* if it spans more than one chip (you usually put the same
|
|
* type of chips in a system)
|
|
*/
|
|
|
|
ssize = mtd->erasesize;
|
|
|
|
if (offset % ssize) {
|
|
printk(KERN_WARNING "jffs_flash_erasable_size() given non-aligned offset %x (erasesize %lx)\n", offset, ssize);
|
|
/* The offset is not sector size aligned. */
|
|
return -1;
|
|
}
|
|
else if (offset > mtd->size) {
|
|
printk(KERN_WARNING "jffs_flash_erasable_size given offset off the end of device (%x > %x)\n", offset, mtd->size);
|
|
return -2;
|
|
}
|
|
else if (offset + size > mtd->size) {
|
|
printk(KERN_WARNING "jffs_flash_erasable_size() given length which runs off the end of device (ofs %x + len %x = %x, > %x)\n", offset,size, offset+size, mtd->size);
|
|
return -3;
|
|
}
|
|
|
|
return (size / ssize) * ssize;
|
|
}
|
|
|
|
|
|
/* How much dirty flash memory is possible to erase at the moment? */
|
|
long
|
|
jffs_erasable_size(struct jffs_fmcontrol *fmc)
|
|
{
|
|
struct jffs_fm *fm;
|
|
__u32 size = 0;
|
|
long ret;
|
|
|
|
ASSERT(if (!fmc) {
|
|
printk(KERN_ERR "jffs_erasable_size(): fmc = NULL\n");
|
|
return -1;
|
|
});
|
|
|
|
if (!fmc->head) {
|
|
/* The flash memory is totally empty. No nodes. No dirt.
|
|
Just return. */
|
|
return 0;
|
|
}
|
|
|
|
/* Calculate how much space that is dirty. */
|
|
for (fm = fmc->head; fm && !fm->nodes; fm = fm->next) {
|
|
if (size && fm->offset == 0) {
|
|
/* We have reached the beginning of the flash. */
|
|
break;
|
|
}
|
|
size += fm->size;
|
|
}
|
|
|
|
/* Someone's signature contained this:
|
|
There's a fine line between fishing and just standing on
|
|
the shore like an idiot... */
|
|
ret = jffs_flash_erasable_size(fmc->mtd, fmc->head->offset, size);
|
|
|
|
ASSERT(if (ret < 0) {
|
|
printk("jffs_erasable_size: flash_erasable_size() "
|
|
"returned something less than zero (%ld).\n", ret);
|
|
printk("jffs_erasable_size: offset = 0x%08x\n",
|
|
fmc->head->offset);
|
|
});
|
|
|
|
/* If there is dirt on the flash (which is the reason to why
|
|
this function was called in the first place) but no space is
|
|
possible to erase right now, the initial part of the list of
|
|
jffs_fm structs, that hold place for dirty space, could perhaps
|
|
be shortened. The list's initial "dirty" elements are merged
|
|
into just one large dirty jffs_fm struct. This operation must
|
|
only be performed if nothing is possible to erase. Otherwise,
|
|
jffs_clear_end_of_node() won't work as expected. */
|
|
if (ret == 0) {
|
|
struct jffs_fm *head = fmc->head;
|
|
struct jffs_fm *del;
|
|
/* While there are two dirty nodes beside each other.*/
|
|
while (head->nodes == 0
|
|
&& head->next
|
|
&& head->next->nodes == 0) {
|
|
del = head->next;
|
|
head->size += del->size;
|
|
head->next = del->next;
|
|
if (del->next) {
|
|
del->next->prev = head;
|
|
}
|
|
jffs_free_fm(del);
|
|
}
|
|
}
|
|
|
|
return (ret >= 0 ? ret : 0);
|
|
}
|
|
|
|
static struct jffs_fm *jffs_alloc_fm(void)
|
|
{
|
|
struct jffs_fm *fm;
|
|
|
|
fm = kmem_cache_alloc(fm_cache,GFP_KERNEL);
|
|
DJM(if (fm) no_jffs_fm++;);
|
|
|
|
return fm;
|
|
}
|
|
|
|
static void jffs_free_fm(struct jffs_fm *n)
|
|
{
|
|
kmem_cache_free(fm_cache,n);
|
|
DJM(no_jffs_fm--);
|
|
}
|
|
|
|
|
|
|
|
struct jffs_node *jffs_alloc_node(void)
|
|
{
|
|
struct jffs_node *n;
|
|
|
|
n = (struct jffs_node *)kmem_cache_alloc(node_cache,GFP_KERNEL);
|
|
if(n != NULL)
|
|
no_jffs_node++;
|
|
return n;
|
|
}
|
|
|
|
void jffs_free_node(struct jffs_node *n)
|
|
{
|
|
kmem_cache_free(node_cache,n);
|
|
no_jffs_node--;
|
|
}
|
|
|
|
|
|
int jffs_get_node_inuse(void)
|
|
{
|
|
return no_jffs_node;
|
|
}
|