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OpenCloudOS-Kernel/fs/jffs2/xattr.c

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/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2006 NEC Corporation
*
* Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include <linux/xattr.h>
#include <linux/mtd/mtd.h>
#include "nodelist.h"
/* -------- xdatum related functions ----------------
* xattr_datum_hashkey(xprefix, xname, xvalue, xsize)
* is used to calcurate xdatum hashkey. The reminder of hashkey into XATTRINDEX_HASHSIZE is
* the index of the xattr name/value pair cache (c->xattrindex).
* unload_xattr_datum(c, xd)
* is used to release xattr name/value pair and detach from c->xattrindex.
* reclaim_xattr_datum(c)
* is used to reclaim xattr name/value pairs on the xattr name/value pair cache when
* memory usage by cache is over c->xdatum_mem_threshold. Currentry, this threshold
* is hard coded as 32KiB.
* delete_xattr_datum_node(c, xd)
* is used to delete a jffs2 node is dominated by xdatum. When EBS(Erase Block Summary) is
* enabled, it overwrites the obsolete node by myself.
* delete_xattr_datum(c, xd)
* is used to delete jffs2_xattr_datum object. It must be called with 0-value of reference
* counter. (It means how many jffs2_xattr_ref object refers this xdatum.)
* do_verify_xattr_datum(c, xd)
* is used to load the xdatum informations without name/value pair from the medium.
* It's necessary once, because those informations are not collected during mounting
* process when EBS is enabled.
* 0 will be returned, if success. An negative return value means recoverable error, and
* positive return value means unrecoverable error. Thus, caller must remove this xdatum
* and xref when it returned positive value.
* do_load_xattr_datum(c, xd)
* is used to load name/value pair from the medium.
* The meanings of return value is same as do_verify_xattr_datum().
* load_xattr_datum(c, xd)
* is used to be as a wrapper of do_verify_xattr_datum() and do_load_xattr_datum().
* If xd need to call do_verify_xattr_datum() at first, it's called before calling
* do_load_xattr_datum(). The meanings of return value is same as do_verify_xattr_datum().
* save_xattr_datum(c, xd)
* is used to write xdatum to medium. xd->version will be incremented.
* create_xattr_datum(c, xprefix, xname, xvalue, xsize)
* is used to create new xdatum and write to medium.
* -------------------------------------------------- */
static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
{
int name_len = strlen(xname);
return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
}
static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
D1(dbg_xattr("%s: xid=%u, version=%u\n", __FUNCTION__, xd->xid, xd->version));
if (xd->xname) {
c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
kfree(xd->xname);
}
list_del_init(&xd->xindex);
xd->hashkey = 0;
xd->xname = NULL;
xd->xvalue = NULL;
}
static void reclaim_xattr_datum(struct jffs2_sb_info *c)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_xattr_datum *xd, *_xd;
uint32_t target, before;
static int index = 0;
int count;
if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
return;
before = c->xdatum_mem_usage;
target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
if (xd->flags & JFFS2_XFLAGS_HOT) {
xd->flags &= ~JFFS2_XFLAGS_HOT;
} else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
unload_xattr_datum(c, xd);
}
if (c->xdatum_mem_usage <= target)
goto out;
}
index = (index+1) % XATTRINDEX_HASHSIZE;
}
out:
JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
}
static void delete_xattr_datum_node(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_raw_xattr rx;
size_t length;
int rc;
if (!xd->node) {
JFFS2_WARNING("xdatum (xid=%u) is removed twice.\n", xd->xid);
return;
}
if (jffs2_sum_active()) {
memset(&rx, 0xff, sizeof(struct jffs2_raw_xattr));
rc = jffs2_flash_read(c, ref_offset(xd->node),
sizeof(struct jffs2_unknown_node),
&length, (char *)&rx);
if (rc || length != sizeof(struct jffs2_unknown_node)) {
JFFS2_ERROR("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
rc, sizeof(struct jffs2_unknown_node),
length, ref_offset(xd->node));
}
rc = jffs2_flash_write(c, ref_offset(xd->node), sizeof(rx),
&length, (char *)&rx);
if (rc || length != sizeof(struct jffs2_raw_xattr)) {
JFFS2_ERROR("jffs2_flash_write()=%d, req=%zu, wrote=%zu ar %#08x\n",
rc, sizeof(rx), length, ref_offset(xd->node));
}
}
spin_lock(&c->erase_completion_lock);
xd->node->next_in_ino = NULL;
spin_unlock(&c->erase_completion_lock);
jffs2_mark_node_obsolete(c, xd->node);
xd->node = NULL;
}
static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
BUG_ON(xd->refcnt);
unload_xattr_datum(c, xd);
if (xd->node) {
delete_xattr_datum_node(c, xd);
xd->node = NULL;
}
jffs2_free_xattr_datum(xd);
}
static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_eraseblock *jeb;
struct jffs2_raw_xattr rx;
size_t readlen;
uint32_t crc, totlen;
int rc;
BUG_ON(!xd->node);
BUG_ON(ref_flags(xd->node) != REF_UNCHECKED);
rc = jffs2_flash_read(c, ref_offset(xd->node), sizeof(rx), &readlen, (char *)&rx);
if (rc || readlen != sizeof(rx)) {
JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
rc, sizeof(rx), readlen, ref_offset(xd->node));
return rc ? rc : -EIO;
}
crc = crc32(0, &rx, sizeof(rx) - 4);
if (crc != je32_to_cpu(rx.node_crc)) {
if (je32_to_cpu(rx.node_crc) != 0xffffffff)
JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
ref_offset(xd->node), je32_to_cpu(rx.hdr_crc), crc);
return EIO;
}
totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
|| je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
|| je32_to_cpu(rx.totlen) != totlen
|| je32_to_cpu(rx.xid) != xd->xid
|| je32_to_cpu(rx.version) != xd->version) {
JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
"nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
ref_offset(xd->node), je16_to_cpu(rx.magic), JFFS2_MAGIC_BITMASK,
je16_to_cpu(rx.nodetype), JFFS2_NODETYPE_XATTR,
je32_to_cpu(rx.totlen), totlen,
je32_to_cpu(rx.xid), xd->xid,
je32_to_cpu(rx.version), xd->version);
return EIO;
}
xd->xprefix = rx.xprefix;
xd->name_len = rx.name_len;
xd->value_len = je16_to_cpu(rx.value_len);
xd->data_crc = je32_to_cpu(rx.data_crc);
/* This JFFS2_NODETYPE_XATTR node is checked */
jeb = &c->blocks[ref_offset(xd->node) / c->sector_size];
totlen = PAD(je32_to_cpu(rx.totlen));
spin_lock(&c->erase_completion_lock);
c->unchecked_size -= totlen; c->used_size += totlen;
jeb->unchecked_size -= totlen; jeb->used_size += totlen;
xd->node->flash_offset = ref_offset(xd->node) | REF_PRISTINE;
spin_unlock(&c->erase_completion_lock);
/* unchecked xdatum is chained with c->xattr_unchecked */
list_del_init(&xd->xindex);
dbg_xattr("success on verfying xdatum (xid=%u, version=%u)\n",
xd->xid, xd->version);
return 0;
}
static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
char *data;
size_t readlen;
uint32_t crc, length;
int i, ret, retry = 0;
BUG_ON(!xd->node);
BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
BUG_ON(!list_empty(&xd->xindex));
retry:
length = xd->name_len + 1 + xd->value_len;
data = kmalloc(length, GFP_KERNEL);
if (!data)
return -ENOMEM;
ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
length, &readlen, data);
if (ret || length!=readlen) {
JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%zu, at %#08x\n",
ret, length, readlen, ref_offset(xd->node));
kfree(data);
return ret ? ret : -EIO;
}
data[xd->name_len] = '\0';
crc = crc32(0, data, length);
if (crc != xd->data_crc) {
JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XREF)"
" at %#08x, read: 0x%08x calculated: 0x%08x\n",
ref_offset(xd->node), xd->data_crc, crc);
kfree(data);
return EIO;
}
xd->flags |= JFFS2_XFLAGS_HOT;
xd->xname = data;
xd->xvalue = data + xd->name_len+1;
c->xdatum_mem_usage += length;
xd->hashkey = xattr_datum_hashkey(xd->xprefix, xd->xname, xd->xvalue, xd->value_len);
i = xd->hashkey % XATTRINDEX_HASHSIZE;
list_add(&xd->xindex, &c->xattrindex[i]);
if (!retry) {
retry = 1;
reclaim_xattr_datum(c);
if (!xd->xname)
goto retry;
}
dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
xd->xid, xd->xprefix, xd->xname);
return 0;
}
static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem);
* rc < 0 : recoverable error, try again
* rc = 0 : success
* rc > 0 : Unrecoverable error, this node should be deleted.
*/
int rc = 0;
BUG_ON(xd->xname);
if (!xd->node)
return EIO;
if (unlikely(ref_flags(xd->node) != REF_PRISTINE)) {
rc = do_verify_xattr_datum(c, xd);
if (rc > 0) {
list_del_init(&xd->xindex);
delete_xattr_datum_node(c, xd);
}
}
if (!rc)
rc = do_load_xattr_datum(c, xd);
return rc;
}
static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_raw_node_ref *raw;
struct jffs2_raw_xattr rx;
struct kvec vecs[2];
size_t length;
int rc, totlen;
uint32_t phys_ofs = write_ofs(c);
BUG_ON(!xd->xname);
vecs[0].iov_base = &rx;
vecs[0].iov_len = PAD(sizeof(rx));
vecs[1].iov_base = xd->xname;
vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
totlen = vecs[0].iov_len + vecs[1].iov_len;
/* Setup raw-xattr */
rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rx.nodetype = cpu_to_je16(JFFS2_NODETYPE_XATTR);
rx.totlen = cpu_to_je32(PAD(totlen));
rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
rx.xid = cpu_to_je32(xd->xid);
rx.version = cpu_to_je32(++xd->version);
rx.xprefix = xd->xprefix;
rx.name_len = xd->name_len;
rx.value_len = cpu_to_je16(xd->value_len);
rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
rc = jffs2_flash_writev(c, vecs, 2, phys_ofs, &length, 0);
if (rc || totlen != length) {
JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
rc, totlen, length, phys_ofs);
rc = rc ? rc : -EIO;
if (length)
jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(totlen), NULL);
return rc;
}
/* success */
raw = jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(totlen), NULL);
/* FIXME */ raw->next_in_ino = (void *)xd;
if (xd->node)
delete_xattr_datum_node(c, xd);
xd->node = raw;
dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
xd->xid, xd->version, xd->xprefix, xd->xname);
return 0;
}
static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
int xprefix, const char *xname,
const char *xvalue, int xsize)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_xattr_datum *xd;
uint32_t hashkey, name_len;
char *data;
int i, rc;
/* Search xattr_datum has same xname/xvalue by index */
hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
i = hashkey % XATTRINDEX_HASHSIZE;
list_for_each_entry(xd, &c->xattrindex[i], xindex) {
if (xd->hashkey==hashkey
&& xd->xprefix==xprefix
&& xd->value_len==xsize
&& !strcmp(xd->xname, xname)
&& !memcmp(xd->xvalue, xvalue, xsize)) {
xd->refcnt++;
return xd;
}
}
/* Not found, Create NEW XATTR-Cache */
name_len = strlen(xname);
xd = jffs2_alloc_xattr_datum();
if (!xd)
return ERR_PTR(-ENOMEM);
data = kmalloc(name_len + 1 + xsize, GFP_KERNEL);
if (!data) {
jffs2_free_xattr_datum(xd);
return ERR_PTR(-ENOMEM);
}
strcpy(data, xname);
memcpy(data + name_len + 1, xvalue, xsize);
xd->refcnt = 1;
xd->xid = ++c->highest_xid;
xd->flags |= JFFS2_XFLAGS_HOT;
xd->xprefix = xprefix;
xd->hashkey = hashkey;
xd->xname = data;
xd->xvalue = data + name_len + 1;
xd->name_len = name_len;
xd->value_len = xsize;
xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
rc = save_xattr_datum(c, xd);
if (rc) {
kfree(xd->xname);
jffs2_free_xattr_datum(xd);
return ERR_PTR(rc);
}
/* Insert Hash Index */
i = hashkey % XATTRINDEX_HASHSIZE;
list_add(&xd->xindex, &c->xattrindex[i]);
c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
reclaim_xattr_datum(c);
return xd;
}
/* -------- xref related functions ------------------
* verify_xattr_ref(c, ref)
* is used to load xref information from medium. Because summary data does not
* contain xid/ino, it's necessary to verify once while mounting process.
* delete_xattr_ref_node(c, ref)
* is used to delete a jffs2 node is dominated by xref. When EBS is enabled,
* it overwrites the obsolete node by myself.
* delete_xattr_ref(c, ref)
* is used to delete jffs2_xattr_ref object. If the reference counter of xdatum
* is refered by this xref become 0, delete_xattr_datum() is called later.
* save_xattr_ref(c, ref)
* is used to write xref to medium.
* create_xattr_ref(c, ic, xd)
* is used to create a new xref and write to medium.
* jffs2_xattr_delete_inode(c, ic)
* is called to remove xrefs related to obsolete inode when inode is unlinked.
* jffs2_xattr_free_inode(c, ic)
* is called to release xattr related objects when unmounting.
* check_xattr_ref_inode(c, ic)
* is used to confirm inode does not have duplicate xattr name/value pair.
* -------------------------------------------------- */
static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
{
struct jffs2_eraseblock *jeb;
struct jffs2_raw_xref rr;
size_t readlen;
uint32_t crc, totlen;
int rc;
BUG_ON(ref_flags(ref->node) != REF_UNCHECKED);
rc = jffs2_flash_read(c, ref_offset(ref->node), sizeof(rr), &readlen, (char *)&rr);
if (rc || sizeof(rr) != readlen) {
JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu, at %#08x\n",
rc, sizeof(rr), readlen, ref_offset(ref->node));
return rc ? rc : -EIO;
}
/* obsolete node */
crc = crc32(0, &rr, sizeof(rr) - 4);
if (crc != je32_to_cpu(rr.node_crc)) {
if (je32_to_cpu(rr.node_crc) != 0xffffffff)
JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
ref_offset(ref->node), je32_to_cpu(rr.node_crc), crc);
return EIO;
}
if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
|| je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
|| je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
"nodetype=%#04x/%#04x, totlen=%u/%zu\n",
ref_offset(ref->node), je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
return EIO;
}
ref->ino = je32_to_cpu(rr.ino);
ref->xid = je32_to_cpu(rr.xid);
/* fixup superblock/eraseblock info */
jeb = &c->blocks[ref_offset(ref->node) / c->sector_size];
totlen = PAD(sizeof(rr));
spin_lock(&c->erase_completion_lock);
c->unchecked_size -= totlen; c->used_size += totlen;
jeb->unchecked_size -= totlen; jeb->used_size += totlen;
ref->node->flash_offset = ref_offset(ref->node) | REF_PRISTINE;
spin_unlock(&c->erase_completion_lock);
dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
ref->ino, ref->xid, ref_offset(ref->node));
return 0;
}
static void delete_xattr_ref_node(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
{
struct jffs2_raw_xref rr;
size_t length;
int rc;
if (jffs2_sum_active()) {
memset(&rr, 0xff, sizeof(rr));
rc = jffs2_flash_read(c, ref_offset(ref->node),
sizeof(struct jffs2_unknown_node),
&length, (char *)&rr);
if (rc || length != sizeof(struct jffs2_unknown_node)) {
JFFS2_ERROR("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
rc, sizeof(struct jffs2_unknown_node),
length, ref_offset(ref->node));
}
rc = jffs2_flash_write(c, ref_offset(ref->node), sizeof(rr),
&length, (char *)&rr);
if (rc || length != sizeof(struct jffs2_raw_xref)) {
JFFS2_ERROR("jffs2_flash_write()=%d, req=%zu, wrote=%zu at %#08x\n",
rc, sizeof(rr), length, ref_offset(ref->node));
}
}
spin_lock(&c->erase_completion_lock);
ref->node->next_in_ino = NULL;
spin_unlock(&c->erase_completion_lock);
jffs2_mark_node_obsolete(c, ref->node);
ref->node = NULL;
}
static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_xattr_datum *xd;
BUG_ON(!ref->node);
delete_xattr_ref_node(c, ref);
xd = ref->xd;
xd->refcnt--;
if (!xd->refcnt)
delete_xattr_datum(c, xd);
jffs2_free_xattr_ref(ref);
}
static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_raw_node_ref *raw;
struct jffs2_raw_xref rr;
size_t length;
uint32_t phys_ofs = write_ofs(c);
int ret;
rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
rr.ino = cpu_to_je32(ref->ic->ino);
rr.xid = cpu_to_je32(ref->xd->xid);
rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
ret = jffs2_flash_write(c, phys_ofs, sizeof(rr), &length, (char *)&rr);
if (ret || sizeof(rr) != length) {
JFFS2_WARNING("jffs2_flash_write() returned %d, request=%zu, retlen=%zu, at %#08x\n",
ret, sizeof(rr), length, phys_ofs);
ret = ret ? ret : -EIO;
if (length)
jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(sizeof(rr)), NULL);
return ret;
}
raw = jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), NULL);
/* FIXME */ raw->next_in_ino = (void *)ref;
if (ref->node)
delete_xattr_ref_node(c, ref);
ref->node = raw;
dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
return 0;
}
static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
struct jffs2_xattr_datum *xd)
{
/* must be called under down_write(xattr_sem) */
struct jffs2_xattr_ref *ref;
int ret;
ref = jffs2_alloc_xattr_ref();
if (!ref)
return ERR_PTR(-ENOMEM);
ref->ic = ic;
ref->xd = xd;
ret = save_xattr_ref(c, ref);
if (ret) {
jffs2_free_xattr_ref(ref);
return ERR_PTR(ret);
}
/* Chain to inode */
ref->next = ic->xref;
ic->xref = ref;
return ref; /* success */
}
void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
{
/* It's called from jffs2_clear_inode() on inode removing.
When an inode with XATTR is removed, those XATTRs must be removed. */
struct jffs2_xattr_ref *ref, *_ref;
if (!ic || ic->nlink > 0)
return;
down_write(&c->xattr_sem);
for (ref = ic->xref; ref; ref = _ref) {
_ref = ref->next;
delete_xattr_ref(c, ref);
}
ic->xref = NULL;
up_write(&c->xattr_sem);
}
void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
{
/* It's called from jffs2_free_ino_caches() until unmounting FS. */
struct jffs2_xattr_datum *xd;
struct jffs2_xattr_ref *ref, *_ref;
down_write(&c->xattr_sem);
for (ref = ic->xref; ref; ref = _ref) {
_ref = ref->next;
xd = ref->xd;
xd->refcnt--;
if (!xd->refcnt) {
unload_xattr_datum(c, xd);
jffs2_free_xattr_datum(xd);
}
jffs2_free_xattr_ref(ref);
}
ic->xref = NULL;
up_write(&c->xattr_sem);
}
static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
{
/* success of check_xattr_ref_inode() means taht inode (ic) dose not have
* duplicate name/value pairs. If duplicate name/value pair would be found,
* one will be removed.
*/
struct jffs2_xattr_ref *ref, *cmp, **pref;
int rc = 0;
if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
return 0;
down_write(&c->xattr_sem);
retry:
rc = 0;
for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
if (!ref->xd->xname) {
rc = load_xattr_datum(c, ref->xd);
if (unlikely(rc > 0)) {
*pref = ref->next;
delete_xattr_ref(c, ref);
goto retry;
} else if (unlikely(rc < 0))
goto out;
}
for (cmp=ref->next, pref=&ref->next; cmp; pref=&cmp->next, cmp=cmp->next) {
if (!cmp->xd->xname) {
ref->xd->flags |= JFFS2_XFLAGS_BIND;
rc = load_xattr_datum(c, cmp->xd);
ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
if (unlikely(rc > 0)) {
*pref = cmp->next;
delete_xattr_ref(c, cmp);
goto retry;
} else if (unlikely(rc < 0))
goto out;
}
if (ref->xd->xprefix == cmp->xd->xprefix
&& !strcmp(ref->xd->xname, cmp->xd->xname)) {
*pref = cmp->next;
delete_xattr_ref(c, cmp);
goto retry;
}
}
}
ic->flags |= INO_FLAGS_XATTR_CHECKED;
out:
up_write(&c->xattr_sem);
return rc;
}
/* -------- xattr subsystem functions ---------------
* jffs2_init_xattr_subsystem(c)
* is used to initialize semaphore and list_head, and some variables.
* jffs2_find_xattr_datum(c, xid)
* is used to lookup xdatum while scanning process.
* jffs2_clear_xattr_subsystem(c)
* is used to release any xattr related objects.
* jffs2_build_xattr_subsystem(c)
* is used to associate xdatum and xref while super block building process.
* jffs2_setup_xattr_datum(c, xid, version)
* is used to insert xdatum while scanning process.
* -------------------------------------------------- */
void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
{
int i;
for (i=0; i < XATTRINDEX_HASHSIZE; i++)
INIT_LIST_HEAD(&c->xattrindex[i]);
INIT_LIST_HEAD(&c->xattr_unchecked);
c->xref_temp = NULL;
init_rwsem(&c->xattr_sem);
c->xdatum_mem_usage = 0;
c->xdatum_mem_threshold = 32 * 1024; /* Default 32KB */
}
static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
{
struct jffs2_xattr_datum *xd;
int i = xid % XATTRINDEX_HASHSIZE;
/* It's only used in scanning/building process. */
BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
list_for_each_entry(xd, &c->xattrindex[i], xindex) {
if (xd->xid==xid)
return xd;
}
return NULL;
}
void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
{
struct jffs2_xattr_datum *xd, *_xd;
struct jffs2_xattr_ref *ref, *_ref;
int i;
for (ref=c->xref_temp; ref; ref = _ref) {
_ref = ref->next;
jffs2_free_xattr_ref(ref);
}
c->xref_temp = NULL;
for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
list_del(&xd->xindex);
if (xd->xname)
kfree(xd->xname);
jffs2_free_xattr_datum(xd);
}
}
}
void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
{
struct jffs2_xattr_ref *ref, *_ref;
struct jffs2_xattr_datum *xd, *_xd;
struct jffs2_inode_cache *ic;
int i, xdatum_count =0, xdatum_unchecked_count = 0, xref_count = 0;
BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
/* Phase.1 */
for (ref=c->xref_temp; ref; ref=_ref) {
_ref = ref->next;
/* checking REF_UNCHECKED nodes */
if (ref_flags(ref->node) != REF_PRISTINE) {
if (verify_xattr_ref(c, ref)) {
delete_xattr_ref_node(c, ref);
jffs2_free_xattr_ref(ref);
continue;
}
}
/* At this point, ref->xid and ref->ino contain XID and inode number.
ref->xd and ref->ic are not valid yet. */
xd = jffs2_find_xattr_datum(c, ref->xid);
ic = jffs2_get_ino_cache(c, ref->ino);
if (!xd || !ic) {
if (ref_flags(ref->node) != REF_UNCHECKED)
JFFS2_WARNING("xref(ino=%u, xid=%u) is orphan. \n",
ref->ino, ref->xid);
delete_xattr_ref_node(c, ref);
jffs2_free_xattr_ref(ref);
continue;
}
ref->xd = xd;
ref->ic = ic;
xd->refcnt++;
ref->next = ic->xref;
ic->xref = ref;
xref_count++;
}
c->xref_temp = NULL;
/* After this, ref->xid/ino are NEVER used. */
/* Phase.2 */
for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
list_del_init(&xd->xindex);
if (!xd->refcnt) {
if (ref_flags(xd->node) != REF_UNCHECKED)
JFFS2_WARNING("orphan xdatum(xid=%u, version=%u) at %#08x\n",
xd->xid, xd->version, ref_offset(xd->node));
delete_xattr_datum(c, xd);
continue;
}
if (ref_flags(xd->node) != REF_PRISTINE) {
dbg_xattr("unchecked xdatum(xid=%u) at %#08x\n",
xd->xid, ref_offset(xd->node));
list_add(&xd->xindex, &c->xattr_unchecked);
xdatum_unchecked_count++;
}
xdatum_count++;
}
}
/* build complete */
JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum (%u unchecked) and "
"%u of xref found.\n", xdatum_count, xdatum_unchecked_count, xref_count);
}
struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
uint32_t xid, uint32_t version)
{
struct jffs2_xattr_datum *xd, *_xd;
_xd = jffs2_find_xattr_datum(c, xid);
if (_xd) {
dbg_xattr("duplicate xdatum (xid=%u, version=%u/%u) at %#08x\n",
xid, version, _xd->version, ref_offset(_xd->node));
if (version < _xd->version)
return ERR_PTR(-EEXIST);
}
xd = jffs2_alloc_xattr_datum();
if (!xd)
return ERR_PTR(-ENOMEM);
xd->xid = xid;
xd->version = version;
if (xd->xid > c->highest_xid)
c->highest_xid = xd->xid;
list_add_tail(&xd->xindex, &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
if (_xd) {
list_del_init(&_xd->xindex);
delete_xattr_datum_node(c, _xd);
jffs2_free_xattr_datum(_xd);
}
return xd;
}
/* -------- xattr subsystem functions ---------------
* xprefix_to_handler(xprefix)
* is used to translate xprefix into xattr_handler.
* jffs2_listxattr(dentry, buffer, size)
* is an implementation of listxattr handler on jffs2.
* do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
* is an implementation of getxattr handler on jffs2.
* do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
* is an implementation of setxattr handler on jffs2.
* -------------------------------------------------- */
struct xattr_handler *jffs2_xattr_handlers[] = {
&jffs2_user_xattr_handler,
#ifdef CONFIG_JFFS2_FS_SECURITY
&jffs2_security_xattr_handler,
#endif
#ifdef CONFIG_JFFS2_FS_POSIX_ACL
&jffs2_acl_access_xattr_handler,
&jffs2_acl_default_xattr_handler,
#endif
&jffs2_trusted_xattr_handler,
NULL
};
static struct xattr_handler *xprefix_to_handler(int xprefix) {
struct xattr_handler *ret;
switch (xprefix) {
case JFFS2_XPREFIX_USER:
ret = &jffs2_user_xattr_handler;
break;
#ifdef CONFIG_JFFS2_FS_SECURITY
case JFFS2_XPREFIX_SECURITY:
ret = &jffs2_security_xattr_handler;
break;
#endif
#ifdef CONFIG_JFFS2_FS_POSIX_ACL
case JFFS2_XPREFIX_ACL_ACCESS:
ret = &jffs2_acl_access_xattr_handler;
break;
case JFFS2_XPREFIX_ACL_DEFAULT:
ret = &jffs2_acl_default_xattr_handler;
break;
#endif
case JFFS2_XPREFIX_TRUSTED:
ret = &jffs2_trusted_xattr_handler;
break;
default:
ret = NULL;
break;
}
return ret;
}
ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
struct inode *inode = dentry->d_inode;
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
struct jffs2_inode_cache *ic = f->inocache;
struct jffs2_xattr_ref *ref, **pref;
struct jffs2_xattr_datum *xd;
struct xattr_handler *xhandle;
ssize_t len, rc;
int retry = 0;
rc = check_xattr_ref_inode(c, ic);
if (unlikely(rc))
return rc;
down_read(&c->xattr_sem);
retry:
len = 0;
for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
BUG_ON(ref->ic != ic);
xd = ref->xd;
if (!xd->xname) {
/* xdatum is unchached */
if (!retry) {
retry = 1;
up_read(&c->xattr_sem);
down_write(&c->xattr_sem);
goto retry;
} else {
rc = load_xattr_datum(c, xd);
if (unlikely(rc > 0)) {
*pref = ref->next;
delete_xattr_ref(c, ref);
goto retry;
} else if (unlikely(rc < 0))
goto out;
}
}
xhandle = xprefix_to_handler(xd->xprefix);
if (!xhandle)
continue;
if (buffer) {
rc = xhandle->list(inode, buffer+len, size-len, xd->xname, xd->name_len);
} else {
rc = xhandle->list(inode, NULL, 0, xd->xname, xd->name_len);
}
if (rc < 0)
goto out;
len += rc;
}
rc = len;
out:
if (!retry) {
up_read(&c->xattr_sem);
} else {
up_write(&c->xattr_sem);
}
return rc;
}
int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
char *buffer, size_t size)
{
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
struct jffs2_inode_cache *ic = f->inocache;
struct jffs2_xattr_datum *xd;
struct jffs2_xattr_ref *ref, **pref;
int rc, retry = 0;
rc = check_xattr_ref_inode(c, ic);
if (unlikely(rc))
return rc;
down_read(&c->xattr_sem);
retry:
for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
BUG_ON(ref->ic!=ic);
xd = ref->xd;
if (xd->xprefix != xprefix)
continue;
if (!xd->xname) {
/* xdatum is unchached */
if (!retry) {
retry = 1;
up_read(&c->xattr_sem);
down_write(&c->xattr_sem);
goto retry;
} else {
rc = load_xattr_datum(c, xd);
if (unlikely(rc > 0)) {
*pref = ref->next;
delete_xattr_ref(c, ref);
goto retry;
} else if (unlikely(rc < 0)) {
goto out;
}
}
}
if (!strcmp(xname, xd->xname)) {
rc = xd->value_len;
if (buffer) {
if (size < rc) {
rc = -ERANGE;
} else {
memcpy(buffer, xd->xvalue, rc);
}
}
goto out;
}
}
rc = -ENODATA;
out:
if (!retry) {
up_read(&c->xattr_sem);
} else {
up_write(&c->xattr_sem);
}
return rc;
}
int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
const char *buffer, size_t size, int flags)
{
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
struct jffs2_inode_cache *ic = f->inocache;
struct jffs2_xattr_datum *xd;
struct jffs2_xattr_ref *ref, *newref, **pref;
uint32_t length, request;
int rc;
rc = check_xattr_ref_inode(c, ic);
if (unlikely(rc))
return rc;
request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
rc = jffs2_reserve_space(c, request, &length,
ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
if (rc) {
JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
return rc;
}
/* Find existing xattr */
down_write(&c->xattr_sem);
retry:
for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
xd = ref->xd;
if (xd->xprefix != xprefix)
continue;
if (!xd->xname) {
rc = load_xattr_datum(c, xd);
if (unlikely(rc > 0)) {
*pref = ref->next;
delete_xattr_ref(c, ref);
goto retry;
} else if (unlikely(rc < 0))
goto out;
}
if (!strcmp(xd->xname, xname)) {
if (flags & XATTR_CREATE) {
rc = -EEXIST;
goto out;
}
if (!buffer) {
*pref = ref->next;
delete_xattr_ref(c, ref);
rc = 0;
goto out;
}
goto found;
}
}
/* not found */
if (flags & XATTR_REPLACE) {
rc = -ENODATA;
goto out;
}
if (!buffer) {
rc = -EINVAL;
goto out;
}
found:
xd = create_xattr_datum(c, xprefix, xname, buffer, size);
if (IS_ERR(xd)) {
rc = PTR_ERR(xd);
goto out;
}
up_write(&c->xattr_sem);
jffs2_complete_reservation(c);
/* create xattr_ref */
request = PAD(sizeof(struct jffs2_raw_xref));
rc = jffs2_reserve_space(c, request, &length,
ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
if (rc) {
JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
down_write(&c->xattr_sem);
xd->refcnt--;
if (!xd->refcnt)
delete_xattr_datum(c, xd);
up_write(&c->xattr_sem);
return rc;
}
down_write(&c->xattr_sem);
if (ref)
*pref = ref->next;
newref = create_xattr_ref(c, ic, xd);
if (IS_ERR(newref)) {
if (ref) {
ref->next = ic->xref;
ic->xref = ref;
}
rc = PTR_ERR(newref);
xd->refcnt--;
if (!xd->refcnt)
delete_xattr_datum(c, xd);
} else if (ref) {
delete_xattr_ref(c, ref);
}
out:
up_write(&c->xattr_sem);
jffs2_complete_reservation(c);
return rc;
}
/* -------- garbage collector functions -------------
* jffs2_garbage_collect_xattr_datum(c, xd)
* is used to move xdatum into new node.
* jffs2_garbage_collect_xattr_ref(c, ref)
* is used to move xref into new node.
* jffs2_verify_xattr(c)
* is used to call do_verify_xattr_datum() before garbage collecting.
* -------------------------------------------------- */
int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
{
uint32_t totlen, length, old_ofs;
int rc = -EINVAL;
down_write(&c->xattr_sem);
BUG_ON(!xd->node);
old_ofs = ref_offset(xd->node);
totlen = ref_totlen(c, c->gcblock, xd->node);
if (totlen < sizeof(struct jffs2_raw_xattr))
goto out;
if (!xd->xname) {
rc = load_xattr_datum(c, xd);
if (unlikely(rc > 0)) {
delete_xattr_datum_node(c, xd);
rc = 0;
goto out;
} else if (unlikely(rc < 0))
goto out;
}
rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
if (rc || length < totlen) {
JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, totlen);
rc = rc ? rc : -EBADFD;
goto out;
}
rc = save_xattr_datum(c, xd);
if (!rc)
dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
xd->xid, xd->version, old_ofs, ref_offset(xd->node));
out:
up_write(&c->xattr_sem);
return rc;
}
int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
{
uint32_t totlen, length, old_ofs;
int rc = -EINVAL;
down_write(&c->xattr_sem);
BUG_ON(!ref->node);
old_ofs = ref_offset(ref->node);
totlen = ref_totlen(c, c->gcblock, ref->node);
if (totlen != sizeof(struct jffs2_raw_xref))
goto out;
rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XREF_SIZE);
if (rc || length < totlen) {
JFFS2_WARNING("%s: jffs2_reserve_space() = %d, request = %u\n",
__FUNCTION__, rc, totlen);
rc = rc ? rc : -EBADFD;
goto out;
}
rc = save_xattr_ref(c, ref);
if (!rc)
dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
out:
up_write(&c->xattr_sem);
return rc;
}
int jffs2_verify_xattr(struct jffs2_sb_info *c)
{
struct jffs2_xattr_datum *xd, *_xd;
int rc;
down_write(&c->xattr_sem);
list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
rc = do_verify_xattr_datum(c, xd);
if (rc == 0) {
list_del_init(&xd->xindex);
break;
} else if (rc > 0) {
list_del_init(&xd->xindex);
delete_xattr_datum_node(c, xd);
}
}
up_write(&c->xattr_sem);
return list_empty(&c->xattr_unchecked) ? 1 : 0;
}
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