cregit-Linux how code gets into the kernel

Release 4.11 fs/jffs2/nodelist.c

Directory: fs/jffs2
/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/mtd/mtd.h>
#include <linux/rbtree.h>
#include <linux/crc32.h>
#include <linux/pagemap.h>
#include "nodelist.h"

static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
				     struct jffs2_node_frag *this);


void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list) { struct jffs2_full_dirent **prev = list; dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino); while ((*prev) && (*prev)->nhash <= new->nhash) { if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) { /* Duplicate. Free one */ if (new->version < (*prev)->version) { dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n", (*prev)->name, (*prev)->ino); jffs2_mark_node_obsolete(c, new->raw); jffs2_free_full_dirent(new); } else { dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n", (*prev)->name, (*prev)->ino); new->next = (*prev)->next; /* It may have been a 'placeholder' deletion dirent, if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */ if ((*prev)->raw) jffs2_mark_node_obsolete(c, ((*prev)->raw)); jffs2_free_full_dirent(*prev); *prev = new; } return; } prev = &((*prev)->next); } new->next = *prev; *prev = new; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds20587.61%125.00%
Artem B. Bityutskiy177.26%250.00%
David Woodhouse125.13%125.00%
Total234100.00%4100.00%


uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size) { struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size); dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size); /* We know frag->ofs <= size. That's what lookup does for us */ if (frag && frag->ofs != size) { if (frag->ofs+frag->size > size) { frag->size = size - frag->ofs; } frag = frag_next(frag); } while (frag && frag->ofs >= size) { struct jffs2_node_frag *next = frag_next(frag); frag_erase(frag, list); jffs2_obsolete_node_frag(c, frag); frag = next; } if (size == 0) return 0; frag = frag_last(list); /* Sanity check for truncation to longer than we started with... */ if (!frag) return 0; if (frag->ofs + frag->size < size) return frag->ofs + frag->size; /* If the last fragment starts at the RAM page boundary, it is * REF_PRISTINE irrespective of its size. */ if (frag->node && (frag->ofs & (PAGE_SIZE - 1)) == 0) { dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n", frag->ofs, frag->ofs + frag->size); frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE; } return size; }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy19082.97%466.67%
David Woodhouse3816.59%116.67%
Kirill A. Shutemov10.44%116.67%
Total229100.00%6100.00%


static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this) { if (this->node) { this->node->frags--; if (!this->node->frags) { /* The node has no valid frags left. It's totally obsoleted */ dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n", ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size); jffs2_mark_node_obsolete(c, this->node->raw); jffs2_free_full_dnode(this->node); } else { dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n", ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags); mark_ref_normal(this->node->raw); } } jffs2_free_node_frag(this); }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy11376.35%350.00%
David Woodhouse1912.84%116.67%
Linus Torvalds1510.14%116.67%
Adrian Bunk10.68%116.67%
Total148100.00%6100.00%


static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base) { struct rb_node *parent = &base->rb; struct rb_node **link = &parent; dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size); while (*link) { parent = *link; base = rb_entry(parent, struct jffs2_node_frag, rb); if (newfrag->ofs > base->ofs) link = &base->rb.rb_right; else if (newfrag->ofs < base->ofs) link = &base->rb.rb_left; else { JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base); BUG(); } } rb_link_node(&newfrag->rb, &base->rb, link); }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy9060.40%350.00%
David Woodhouse5939.60%350.00%
Total149100.00%6100.00%

/* * Allocate and initializes a new fragment. */
static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size) { struct jffs2_node_frag *newfrag; newfrag = jffs2_alloc_node_frag(); if (likely(newfrag)) { newfrag->ofs = ofs; newfrag->size = size; newfrag->node = fn; } else { JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n"); } return newfrag; }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy67100.00%1100.00%
Total67100.00%1100.00%

/* * Called when there is no overlapping fragment exist. Inserts a hole before the new * fragment and inserts the new fragment to the fragtree. */
static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag, struct jffs2_node_frag *this, uint32_t lastend) { if (lastend < newfrag->node->ofs) { /* put a hole in before the new fragment */ struct jffs2_node_frag *holefrag; holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend); if (unlikely(!holefrag)) { jffs2_free_node_frag(newfrag); return -ENOMEM; } if (this) { /* By definition, the 'this' node has no right-hand child, because there are no frags with offset greater than it. So that's where we want to put the hole */ dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n", holefrag->ofs, holefrag->ofs + holefrag->size); rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right); } else { dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n", holefrag->ofs, holefrag->ofs + holefrag->size); rb_link_node(&holefrag->rb, NULL, &root->rb_node); } rb_insert_color(&holefrag->rb, root); this = holefrag; } if (this) { /* By definition, the 'this' node has no right-hand child, because there are no frags with offset greater than it. So that's where we want to put new fragment */ dbg_fragtree2("add the new node at the right\n"); rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right); } else { dbg_fragtree2("insert the new node at the root of the tree\n"); rb_link_node(&newfrag->rb, NULL, &root->rb_node); } rb_insert_color(&newfrag->rb, root); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy20383.20%538.46%
Linus Torvalds208.20%17.69%
David Woodhouse176.97%430.77%
Thomas Gleixner20.82%17.69%
Todd Android Poynor10.41%17.69%
Dave Jones10.41%17.69%
Total244100.00%13100.00%

/* Doesn't set inode->i_size */
static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag) { struct jffs2_node_frag *this; uint32_t lastend; /* Skip all the nodes which are completed before this one starts */ this = jffs2_lookup_node_frag(root, newfrag->node->ofs); if (this) { dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n", this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this); lastend = this->ofs + this->size; } else { dbg_fragtree2("lookup gave no frag\n"); lastend = 0; } /* See if we ran off the end of the fragtree */ if (lastend <= newfrag->ofs) { /* We did */ /* Check if 'this' node was on the same page as the new node. If so, both 'this' and the new node get marked REF_NORMAL so the GC can take a look. */ if (lastend && (lastend-1) >> PAGE_SHIFT == newfrag->ofs >> PAGE_SHIFT) { if (this->node) mark_ref_normal(this->node->raw); mark_ref_normal(newfrag->node->raw); } return no_overlapping_node(c, root, newfrag, this, lastend); } if (this->node) dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n", this->ofs, this->ofs + this->size, ref_offset(this->node->raw), ref_flags(this->node->raw)); else dbg_fragtree2("dealing with hole frag %u-%u.\n", this->ofs, this->ofs + this->size); /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes, * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs */ if (newfrag->ofs > this->ofs) { /* This node isn't completely obsoleted. The start of it remains valid */ /* Mark the new node and the partially covered node REF_NORMAL -- let the GC take a look at them */ mark_ref_normal(newfrag->node->raw); if (this->node) mark_ref_normal(this->node->raw); if (this->ofs + this->size > newfrag->ofs + newfrag->size) { /* The new node splits 'this' frag into two */ struct jffs2_node_frag *newfrag2; if (this->node) dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n", this->ofs, this->ofs+this->size, ref_offset(this->node->raw)); else dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n", this->ofs, this->ofs+this->size); /* New second frag pointing to this's node */ newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size, this->ofs + this->size - newfrag->ofs - newfrag->size); if (unlikely(!newfrag2)) return -ENOMEM; if (this->node) this->node->frags++; /* Adjust size of original 'this' */ this->size = newfrag->ofs - this->ofs; /* Now, we know there's no node with offset greater than this->ofs but smaller than newfrag2->ofs or newfrag->ofs, for obvious reasons. So we can do a tree insert from 'this' to insert newfrag, and a tree insert from newfrag to insert newfrag2. */ jffs2_fragtree_insert(newfrag, this); rb_insert_color(&newfrag->rb, root); jffs2_fragtree_insert(newfrag2, newfrag); rb_insert_color(&newfrag2->rb, root); return 0; } /* New node just reduces 'this' frag in size, doesn't split it */ this->size = newfrag->ofs - this->ofs; /* Again, we know it lives down here in the tree */ jffs2_fragtree_insert(newfrag, this); rb_insert_color(&newfrag->rb, root); } else { /* New frag starts at the same point as 'this' used to. Replace it in the tree without doing a delete and insertion */ dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n", newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size); rb_replace_node(&this->rb, &newfrag->rb, root); if (newfrag->ofs + newfrag->size >= this->ofs+this->size) { dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size); jffs2_obsolete_node_frag(c, this); } else { this->ofs += newfrag->size; this->size -= newfrag->size; jffs2_fragtree_insert(this, newfrag); rb_insert_color(&this->rb, root); return 0; } } /* OK, now we have newfrag added in the correct place in the tree, but frag_next(newfrag) may be a fragment which is overlapped by it */ while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) { /* 'this' frag is obsoleted completely. */ dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n", this, this->ofs, this->ofs+this->size); rb_erase(&this->rb, root); jffs2_obsolete_node_frag(c, this); } /* Now we're pointing at the first frag which isn't totally obsoleted by the new frag */ if (!this || newfrag->ofs + newfrag->size == this->ofs) return 0; /* Still some overlap but we don't need to move it in the tree */ this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size); this->ofs = newfrag->ofs + newfrag->size; /* And mark them REF_NORMAL so the GC takes a look at them */ if (this->node) mark_ref_normal(this->node->raw); mark_ref_normal(newfrag->node->raw); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy69989.27%545.45%
David Woodhouse516.51%327.27%
Linus Torvalds273.45%19.09%
Thomas Gleixner40.51%19.09%
Kirill A. Shutemov20.26%19.09%
Total783100.00%11100.00%

/* * Given an inode, probably with existing tree of fragments, add the new node * to the fragment tree. */
int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn) { int ret; struct jffs2_node_frag *newfrag; if (unlikely(!fn->size)) return 0; newfrag = new_fragment(fn, fn->ofs, fn->size); if (unlikely(!newfrag)) return -ENOMEM; newfrag->node->frags = 1; dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n", fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag); ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag); if (unlikely(ret)) return ret; /* If we now share a page with other nodes, mark either previous or next node REF_NORMAL, as appropriate. */ if (newfrag->ofs & (PAGE_SIZE-1)) { struct jffs2_node_frag *prev = frag_prev(newfrag); mark_ref_normal(fn->raw); /* If we don't start at zero there's _always_ a previous */ if (prev->node) mark_ref_normal(prev->node->raw); } if ((newfrag->ofs+newfrag->size) & (PAGE_SIZE-1)) { struct jffs2_node_frag *next = frag_next(newfrag); if (next) { mark_ref_normal(fn->raw); if (next->node) mark_ref_normal(next->node->raw); } } jffs2_dbg_fragtree_paranoia_check_nolock(f); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Artem B. Bityutskiy19380.42%555.56%
David Woodhouse4518.75%333.33%
Kirill A. Shutemov20.83%111.11%
Total240100.00%9100.00%


void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state) { spin_lock(&c->inocache_lock); ic->state = state; wake_up(&c->inocache_wq); spin_unlock(&c->inocache_lock); }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse48100.00%1100.00%
Total48100.00%1100.00%

/* During mount, this needs no locking. During normal operation, its callers want to do other stuff while still holding the inocache_lock. Rather than introducing special case get_ino_cache functions or callbacks, we just let the caller do the locking itself. */
struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino) { struct jffs2_inode_cache *ret; ret = c->inocache_list[ino % c->inocache_hashsize]; while (ret && ret->ino < ino) { ret = ret->next; } if (ret && ret->ino != ino) ret = NULL; return ret; }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse6595.59%266.67%
Daniel Drake34.41%133.33%
Total68100.00%3100.00%


void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new) { struct jffs2_inode_cache **prev; spin_lock(&c->inocache_lock); if (!new->ino) new->ino = ++c->highest_ino; dbg_inocache("add %p (ino #%u)\n", new, new->ino); prev = &c->inocache_list[new->ino % c->inocache_hashsize]; while ((*prev) && (*prev)->ino < new->ino) { prev = &(*prev)->next; } new->next = *prev; *prev = new; spin_unlock(&c->inocache_lock); }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse11795.90%240.00%
Daniel Drake32.46%120.00%
Artem B. Bityutskiy21.64%240.00%
Total122100.00%5100.00%


void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old) { struct jffs2_inode_cache **prev; #ifdef CONFIG_JFFS2_FS_XATTR BUG_ON(old->xref); #endif dbg_inocache("del %p (ino #%u)\n", old, old->ino); spin_lock(&c->inocache_lock); prev = &c->inocache_list[old->ino % c->inocache_hashsize]; while ((*prev) && (*prev)->ino < old->ino) { prev = &(*prev)->next; } if ((*prev) == old) { *prev = old->next; } /* Free it now unless it's in READING or CLEARING state, which are the transitions upon read_inode() and clear_inode(). The rest of the time we know nobody else is looking at it, and if it's held by read_inode() or clear_inode() they'll free it for themselves. */ if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING) jffs2_free_inode_cache(old); spin_unlock(&c->inocache_lock); }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse12687.50%228.57%
KaiGai Kohei128.33%114.29%
Daniel Drake32.08%114.29%
Artem B. Bityutskiy21.39%228.57%
Thomas Gleixner10.69%114.29%
Total144100.00%7100.00%


void jffs2_free_ino_caches(struct jffs2_sb_info *c) { int i; struct jffs2_inode_cache *this, *next; for (i=0; i < c->inocache_hashsize; i++) { this = c->inocache_list[i]; while (this) { next = this->next; jffs2_xattr_free_inode(c, this); jffs2_free_inode_cache(this); this = next; } c->inocache_list[i] = NULL; } }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse7488.10%133.33%
KaiGai Kohei78.33%133.33%
Daniel Drake33.57%133.33%
Total84100.00%3100.00%


void jffs2_free_raw_node_refs(struct jffs2_sb_info *c) { int i; struct jffs2_raw_node_ref *this, *next; for (i=0; i<c->nr_blocks; i++) { this = c->blocks[i].first_node; while (this) { if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE) next = this[REFS_PER_BLOCK].next_in_ino; else next = NULL; jffs2_free_refblock(this); this = next; } c->blocks[i].first_node = c->blocks[i].last_node = NULL; } }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse10697.25%266.67%
Linus Torvalds32.75%133.33%
Total109100.00%3100.00%


struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset) { /* The common case in lookup is that there will be a node which precisely matches. So we go looking for that first */ struct rb_node *next; struct jffs2_node_frag *prev = NULL; struct jffs2_node_frag *frag = NULL; dbg_fragtree2("root %p, offset %d\n", fragtree, offset); next = fragtree->rb_node; while(next) { frag = rb_entry(next, struct jffs2_node_frag, rb); if (frag->ofs + frag->size <= offset) { /* Remember the closest smaller match on the way down */ if (!prev || frag->ofs > prev->ofs) prev = frag; next = frag->rb.rb_right; } else if (frag->ofs > offset) { next = frag->rb.rb_left; } else { return frag; } } /* Exact match not found. Go back up looking at each parent, and return the closest smaller one */ if (prev) dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n", prev->ofs, prev->ofs+prev->size); else dbg_fragtree2("returning NULL, empty fragtree\n"); return prev; }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse12274.39%120.00%
Linus Torvalds3521.34%120.00%
Artem B. Bityutskiy63.66%240.00%
Thomas Gleixner10.61%120.00%
Total164100.00%5100.00%

/* Pass 'c' argument to indicate that nodes should be marked obsolete as they're killed. */
void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c) { struct jffs2_node_frag *frag, *next; dbg_fragtree("killing\n"); rbtree_postorder_for_each_entry_safe(frag, next, root, rb) { if (frag->node && !(--frag->node->frags)) { /* Not a hole, and it's the final remaining frag of this node. Free the node */ if (c) jffs2_mark_node_obsolete(c, frag->node->raw); jffs2_free_full_dnode(frag->node); } jffs2_free_node_frag(frag); cond_resched(); } }

Contributors

PersonTokensPropCommitsCommitProp
David Woodhouse4651.69%228.57%
Linus Torvalds2932.58%114.29%
Cody P Schafer88.99%114.29%
Artem B. Bityutskiy55.62%228.57%
Thomas Gleixner11.12%114.29%
Total89100.00%7100.00%


struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t ofs, uint32_t len, struct jffs2_inode_cache *ic) { struct jffs2_raw_node_ref *ref; BUG_ON(!jeb->allocated_refs); jeb->allocated_refs--; ref = jeb->last_node; dbg_noderef("Last node at %p is (%08x,%p)\n", ref,