Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 371 insertions, 0 deletions

diff --git a/fs/jffs2/build.c b/fs/jffs2/build.c
new file mode 100644
index 000000000000..a01dd5fdbb95
--- /dev/null
+++ b/fs/jffs2/build.c
@@ -0,0 +1,371 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2001-2003 Red Hat, Inc.
+ *
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: build.c,v 1.69 2004/12/16 20:22:18 dmarlin Exp $
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
+#include "nodelist.h"
+
+static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *, struct jffs2_inode_cache *, struct jffs2_full_dirent **);
+
+static inline struct jffs2_inode_cache *
+first_inode_chain(int *i, struct jffs2_sb_info *c)
+{
+        for (; *i < INOCACHE_HASHSIZE; (*i)++) {
+                if (c->inocache_list[*i])
+                        return c->inocache_list[*i];
+        }
+        return NULL;
+}
+
+static inline struct jffs2_inode_cache *
+next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c)
+{
+        /* More in this chain? */
+        if (ic->next)
+                return ic->next;
+        (*i)++;
+        return first_inode_chain(i, c);
+}
+
+#define for_each_inode(i, c, ic)                        \
+        for (i = 0, ic = first_inode_chain(&i, (c));    \
+             ic;                                        \
+             ic = next_inode(&i, ic, (c)))
+
+
+static inline void jffs2_build_inode_pass1(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+        struct jffs2_full_dirent *fd;
+
+        D1(printk(KERN_DEBUG "jffs2_build_inode building directory inode #%u\n", ic->ino));
+
+        /* For each child, increase nlink */
+        for(fd = ic->scan_dents; fd; fd = fd->next) {
+                struct jffs2_inode_cache *child_ic;
+                if (!fd->ino)
+                        continue;
+
+                /* XXX: Can get high latency here with huge directories */
+
+                child_ic = jffs2_get_ino_cache(c, fd->ino);
+                if (!child_ic) {
+                        printk(KERN_NOTICE "Eep. Child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
+                                  fd->name, fd->ino, ic->ino);
+                        jffs2_mark_node_obsolete(c, fd->raw);
+                        continue;
+                }
+
+                if (child_ic->nlink++ && fd->type == DT_DIR) {
+                        printk(KERN_NOTICE "Child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", fd->name, fd->ino, ic->ino);
+                        if (fd->ino == 1 && ic->ino == 1) {
+                                printk(KERN_NOTICE "This is mostly harmless, and probably caused by creating a JFFS2 image\n");
+                                printk(KERN_NOTICE "using a buggy version of mkfs.jffs2. Use at least v1.17.\n");
+                        }
+                        /* What do we do about it? */
+                }
+                D1(printk(KERN_DEBUG "Increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino));
+                /* Can't free them. We might need them in pass 2 */
+        }
+}
+
+/* Scan plan:
+ - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go
+ - Scan directory tree from top down, setting nlink in inocaches
+ - Scan inocaches for inodes with nlink==0
+*/
+static int jffs2_build_filesystem(struct jffs2_sb_info *c)
+{
+        int ret;
+        int i;
+        struct jffs2_inode_cache *ic;
+        struct jffs2_full_dirent *fd;
+        struct jffs2_full_dirent *dead_fds = NULL;
+
+        /* First, scan the medium and build all the inode caches with
+           lists of physical nodes */
+
+        c->flags |= JFFS2_SB_FLAG_MOUNTING;
+        ret = jffs2_scan_medium(c);
+        if (ret)
+                goto exit;
+
+        D1(printk(KERN_DEBUG "Scanned flash completely\n"));
+        D2(jffs2_dump_block_lists(c));
+
+        /* Now scan the directory tree, increasing nlink according to every dirent found. */
+        for_each_inode(i, c, ic) {
+                D1(printk(KERN_DEBUG "Pass 1: ino #%u\n", ic->ino));
+
+                D1(BUG_ON(ic->ino > c->highest_ino));
+
+                if (ic->scan_dents) {
+                        jffs2_build_inode_pass1(c, ic);
+                        cond_resched();
+                }
+        }
+        c->flags &= ~JFFS2_SB_FLAG_MOUNTING;
+
+        D1(printk(KERN_DEBUG "Pass 1 complete\n"));
+
+        /* Next, scan for inodes with nlink == 0 and remove them. If
+           they were directories, then decrement the nlink of their
+           children too, and repeat the scan. As that's going to be
+           a fairly uncommon occurrence, it's not so evil to do it this
+           way. Recursion bad. */
+        D1(printk(KERN_DEBUG "Pass 2 starting\n"));
+
+        for_each_inode(i, c, ic) {
+                D1(printk(KERN_DEBUG "Pass 2: ino #%u, nlink %d, ic %p, nodes %p\n", ic->ino, ic->nlink, ic, ic->nodes));
+                if (ic->nlink)
+                        continue;
+                        
+                jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
+                cond_resched();
+        } 
+
+        D1(printk(KERN_DEBUG "Pass 2a starting\n"));
+
+        while (dead_fds) {
+                fd = dead_fds;
+                dead_fds = fd->next;
+
+                ic = jffs2_get_ino_cache(c, fd->ino);
+                D1(printk(KERN_DEBUG "Removing dead_fd ino #%u (\"%s\"), ic at %p\n", fd->ino, fd->name, ic));
+
+                if (ic)
+                        jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
+                jffs2_free_full_dirent(fd);
+        }
+
+        D1(printk(KERN_DEBUG "Pass 2 complete\n"));
+        
+        /* Finally, we can scan again and free the dirent structs */
+        for_each_inode(i, c, ic) {
+                D1(printk(KERN_DEBUG "Pass 3: ino #%u, ic %p, nodes %p\n", ic->ino, ic, ic->nodes));
+
+                while(ic->scan_dents) {
+                        fd = ic->scan_dents;
+                        ic->scan_dents = fd->next;
+                        jffs2_free_full_dirent(fd);
+                }
+                ic->scan_dents = NULL;
+                cond_resched();
+        }
+        D1(printk(KERN_DEBUG "Pass 3 complete\n"));
+        D2(jffs2_dump_block_lists(c));
+
+        /* Rotate the lists by some number to ensure wear levelling */
+        jffs2_rotate_lists(c);
+
+        ret = 0;
+
+exit:
+        if (ret) {
+                for_each_inode(i, c, ic) {
+                        while(ic->scan_dents) {
+                                fd = ic->scan_dents;
+                                ic->scan_dents = fd->next;
+                                jffs2_free_full_dirent(fd);
+                        }
+                }
+        }
+
+        return ret;
+}
+
+static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, struct jffs2_full_dirent **dead_fds)
+{
+        struct jffs2_raw_node_ref *raw;
+        struct jffs2_full_dirent *fd;
+
+        D1(printk(KERN_DEBUG "JFFS2: Removing ino #%u with nlink == zero.\n", ic->ino));
+        
+        raw = ic->nodes;
+        while (raw != (void *)ic) {
+                struct jffs2_raw_node_ref *next = raw->next_in_ino;
+                D1(printk(KERN_DEBUG "obsoleting node at 0x%08x\n", ref_offset(raw)));
+                jffs2_mark_node_obsolete(c, raw);
+                raw = next;
+        }
+
+        if (ic->scan_dents) {
+                int whinged = 0;
+                D1(printk(KERN_DEBUG "Inode #%u was a directory which may have children...\n", ic->ino));
+
+                while(ic->scan_dents) {
+                        struct jffs2_inode_cache *child_ic;
+
+                        fd = ic->scan_dents;
+                        ic->scan_dents = fd->next;
+
+                        if (!fd->ino) {
+                                /* It's a deletion dirent. Ignore it */
+                                D1(printk(KERN_DEBUG "Child \"%s\" is a deletion dirent, skipping...\n", fd->name));
+                                jffs2_free_full_dirent(fd);
+                                continue;
+                        }
+                        if (!whinged) {
+                                whinged = 1;
+                                printk(KERN_NOTICE "Inode #%u was a directory with children - removing those too...\n", ic->ino);
+                        }
+
+                        D1(printk(KERN_DEBUG "Removing child \"%s\", ino #%u\n",
+                                  fd->name, fd->ino));
+                        
+                        child_ic = jffs2_get_ino_cache(c, fd->ino);
+                        if (!child_ic) {
+                                printk(KERN_NOTICE "Cannot remove child \"%s\", ino #%u, because it doesn't exist\n", fd->name, fd->ino);
+                                jffs2_free_full_dirent(fd);
+                                continue;
+                        }
+
+                        /* Reduce nlink of the child. If it's now zero, stick it on the 
+                           dead_fds list to be cleaned up later. Else just free the fd */
+
+                        child_ic->nlink--;
+                        
+                        if (!child_ic->nlink) {
+                                D1(printk(KERN_DEBUG "Inode #%u (\"%s\") has now got zero nlink. Adding to dead_fds list.\n",
+                                          fd->ino, fd->name));
+                                fd->next = *dead_fds;
+                                *dead_fds = fd;
+                        } else {
+                                D1(printk(KERN_DEBUG "Inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
+                                          fd->ino, fd->name, child_ic->nlink));
+                                jffs2_free_full_dirent(fd);
+                        }
+                }
+        }
+
+        /*
+           We don't delete the inocache from the hash list and free it yet. 
+           The erase code will do that, when all the nodes are completely gone.
+        */
+}
+
+static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c)
+{
+        uint32_t size;
+
+        /* Deletion should almost _always_ be allowed. We're fairly
+           buggered once we stop allowing people to delete stuff
+           because there's not enough free space... */
+        c->resv_blocks_deletion = 2;
+
+        /* Be conservative about how much space we need before we allow writes. 
+           On top of that which is required for deletia, require an extra 2%
+           of the medium to be available, for overhead caused by nodes being
+           split across blocks, etc. */
+
+        size = c->flash_size / 50; /* 2% of flash size */
+        size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */
+        size += c->sector_size - 1; /* ... and round up */
+
+        c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
+
+        /* When do we let the GC thread run in the background */
+
+        c->resv_blocks_gctrigger = c->resv_blocks_write + 1;
+
+        /* When do we allow garbage collection to merge nodes to make 
+           long-term progress at the expense of short-term space exhaustion? */
+        c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1;
+
+        /* When do we allow garbage collection to eat from bad blocks rather
+           than actually making progress? */
+        c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2;
+
+        /* If there's less than this amount of dirty space, don't bother
+           trying to GC to make more space. It'll be a fruitless task */
+        c->nospc_dirty_size = c->sector_size + (c->flash_size / 100);
+
+        D1(printk(KERN_DEBUG "JFFS2 trigger levels (size %d KiB, block size %d KiB, %d blocks)\n",
+                  c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks));
+        D1(printk(KERN_DEBUG "Blocks required to allow deletion:    %d (%d KiB)\n",
+                  c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024));
+        D1(printk(KERN_DEBUG "Blocks required to allow writes:      %d (%d KiB)\n",
+                  c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024));
+        D1(printk(KERN_DEBUG "Blocks required to quiesce GC thread: %d (%d KiB)\n",
+                  c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024));
+        D1(printk(KERN_DEBUG "Blocks required to allow GC merges:   %d (%d KiB)\n",
+                  c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024));
+        D1(printk(KERN_DEBUG "Blocks required to GC bad blocks:     %d (%d KiB)\n",
+                  c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024));
+        D1(printk(KERN_DEBUG "Amount of dirty space required to GC: %d bytes\n",
+                  c->nospc_dirty_size));
+} 
+
+int jffs2_do_mount_fs(struct jffs2_sb_info *c)
+{
+        int i;
+
+        c->free_size = c->flash_size;
+        c->nr_blocks = c->flash_size / c->sector_size;
+        if (c->mtd->flags & MTD_NO_VIRTBLOCKS)
+                c->blocks = vmalloc(sizeof(struct jffs2_eraseblock) * c->nr_blocks);
+        else
+                c->blocks = kmalloc(sizeof(struct jffs2_eraseblock) * c->nr_blocks, GFP_KERNEL);
+        if (!c->blocks)
+                return -ENOMEM;
+        for (i=0; i<c->nr_blocks; i++) {
+                INIT_LIST_HEAD(&c->blocks[i].list);
+                c->blocks[i].offset = i * c->sector_size;
+                c->blocks[i].free_size = c->sector_size;
+                c->blocks[i].dirty_size = 0;
+                c->blocks[i].wasted_size = 0;
+                c->blocks[i].unchecked_size = 0;
+                c->blocks[i].used_size = 0;
+                c->blocks[i].first_node = NULL;
+                c->blocks[i].last_node = NULL;
+                c->blocks[i].bad_count = 0;
+        }
+
+        init_MUTEX(&c->alloc_sem);
+        init_MUTEX(&c->erase_free_sem);
+        init_waitqueue_head(&c->erase_wait);
+        init_waitqueue_head(&c->inocache_wq);
+        spin_lock_init(&c->erase_completion_lock);
+        spin_lock_init(&c->inocache_lock);
+
+        INIT_LIST_HEAD(&c->clean_list);
+        INIT_LIST_HEAD(&c->very_dirty_list);
+        INIT_LIST_HEAD(&c->dirty_list);
+        INIT_LIST_HEAD(&c->erasable_list);
+        INIT_LIST_HEAD(&c->erasing_list);
+        INIT_LIST_HEAD(&c->erase_pending_list);
+        INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
+        INIT_LIST_HEAD(&c->erase_complete_list);
+        INIT_LIST_HEAD(&c->free_list);
+        INIT_LIST_HEAD(&c->bad_list);
+        INIT_LIST_HEAD(&c->bad_used_list);
+        c->highest_ino = 1;
+
+        if (jffs2_build_filesystem(c)) {
+                D1(printk(KERN_DEBUG "build_fs failed\n"));
+                jffs2_free_ino_caches(c);
+                jffs2_free_raw_node_refs(c);
+                if (c->mtd->flags & MTD_NO_VIRTBLOCKS) {
+                        vfree(c->blocks);
+                } else {
+                        kfree(c->blocks);
+                }
+                return -EIO;
+        }
+
+        jffs2_calc_trigger_levels(c);
+
+        return 0;
+}