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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/jffs2/xattr.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/jffs2/xattr.c')
-rw-r--r--fs/jffs2/xattr.c1352
1 files changed, 1352 insertions, 0 deletions
diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c
new file mode 100644
index 000000000..acb4492f5
--- /dev/null
+++ b/fs/jffs2/xattr.c
@@ -0,0 +1,1352 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2006 NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define JFFS2_XATTR_IS_CORRUPTED 1
+
+#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/posix_acl_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).
+ * is_xattr_datum_unchecked(c, xd)
+ * returns 1, if xdatum contains any unchecked raw nodes. if all raw nodes are not
+ * unchecked, it returns 0.
+ * 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. Currently, this threshold
+ * is hard coded as 32KiB.
+ * 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.
+ * unrefer_xattr_datum(c, xd)
+ * is used to delete a xdatum. When nobody refers this xdatum, JFFS2_XFLAGS_DEAD
+ * is set on xd->flags and chained xattr_dead_list or release it immediately.
+ * In the first case, the garbage collector release it later.
+ * -------------------------------------------------- */
+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 int is_xattr_datum_unchecked(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+ struct jffs2_raw_node_ref *raw;
+ int rc = 0;
+
+ spin_lock(&c->erase_completion_lock);
+ for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
+ if (ref_flags(raw) == REF_UNCHECKED) {
+ rc = 1;
+ break;
+ }
+ }
+ spin_unlock(&c->erase_completion_lock);
+ return rc;
+}
+
+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", __func__, 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 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_node_ref *raw;
+ struct jffs2_raw_xattr rx;
+ size_t readlen;
+ uint32_t crc, offset, totlen;
+ int rc;
+
+ spin_lock(&c->erase_completion_lock);
+ offset = ref_offset(xd->node);
+ if (ref_flags(xd->node) == REF_PRISTINE)
+ goto complete;
+ spin_unlock(&c->erase_completion_lock);
+
+ rc = jffs2_flash_read(c, offset, 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, offset);
+ return rc ? rc : -EIO;
+ }
+ crc = crc32(0, &rx, sizeof(rx) - 4);
+ if (crc != je32_to_cpu(rx.node_crc)) {
+ JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+ offset, je32_to_cpu(rx.hdr_crc), crc);
+ xd->flags |= JFFS2_XFLAGS_INVALID;
+ return JFFS2_XATTR_IS_CORRUPTED;
+ }
+ 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",
+ offset, 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);
+ xd->flags |= JFFS2_XFLAGS_INVALID;
+ return JFFS2_XATTR_IS_CORRUPTED;
+ }
+ 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);
+
+ spin_lock(&c->erase_completion_lock);
+ complete:
+ for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
+ jeb = &c->blocks[ref_offset(raw) / c->sector_size];
+ totlen = PAD(ref_totlen(c, jeb, raw));
+ if (ref_flags(raw) == REF_UNCHECKED) {
+ c->unchecked_size -= totlen; c->used_size += totlen;
+ jeb->unchecked_size -= totlen; jeb->used_size += totlen;
+ }
+ raw->flash_offset = ref_offset(raw) | ((xd->node==raw) ? REF_PRISTINE : REF_NORMAL);
+ }
+ spin_unlock(&c->erase_completion_lock);
+
+ /* unchecked xdatum is chained with c->xattr_unchecked */
+ list_del_init(&xd->xindex);
+
+ dbg_xattr("success on verifying 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(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_XATTR)"
+ " at %#08x, read: 0x%08x calculated: 0x%08x\n",
+ ref_offset(xd->node), xd->data_crc, crc);
+ kfree(data);
+ xd->flags |= JFFS2_XFLAGS_INVALID;
+ return JFFS2_XATTR_IS_CORRUPTED;
+ }
+
+ 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->flags & JFFS2_XFLAGS_DEAD);
+ if (xd->xname)
+ return 0;
+ if (xd->flags & JFFS2_XFLAGS_INVALID)
+ return JFFS2_XATTR_IS_CORRUPTED;
+ if (unlikely(is_xattr_datum_unchecked(c, xd)))
+ rc = do_verify_xattr_datum(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_xattr rx;
+ struct kvec vecs[2];
+ size_t length;
+ int rc, totlen;
+ uint32_t phys_ofs = write_ofs(c);
+
+ BUG_ON(!xd->xname);
+ BUG_ON(xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID));
+
+ vecs[0].iov_base = &rx;
+ vecs[0].iov_len = 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 */
+ memset(&rx, 0, sizeof(rx));
+ 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 */
+ jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(totlen), (void *)xd);
+
+ 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)) {
+ atomic_inc(&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);
+
+ atomic_set(&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;
+}
+
+static void unrefer_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+ /* must be called under down_write(xattr_sem) */
+ if (atomic_dec_and_lock(&xd->refcnt, &c->erase_completion_lock)) {
+ unload_xattr_datum(c, xd);
+ xd->flags |= JFFS2_XFLAGS_DEAD;
+ if (xd->node == (void *)xd) {
+ BUG_ON(!(xd->flags & JFFS2_XFLAGS_INVALID));
+ jffs2_free_xattr_datum(xd);
+ } else {
+ list_add(&xd->xindex, &c->xattr_dead_list);
+ }
+ spin_unlock(&c->erase_completion_lock);
+
+ dbg_xattr("xdatum(xid=%u, version=%u) was removed.\n",
+ xd->xid, xd->version);
+ }
+}
+
+/* -------- 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.
+ * save_xattr_ref(c, ref)
+ * is used to write xref to medium. If delete marker is marked, it write
+ * a delete marker of xref into medium.
+ * create_xattr_ref(c, ic, xd)
+ * is used to create a new xref and write to medium.
+ * delete_xattr_ref(c, ref)
+ * is used to delete jffs2_xattr_ref. It marks xref XREF_DELETE_MARKER,
+ * and allows GC to reclaim those physical nodes.
+ * 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.
+ * jffs2_xattr_do_crccheck_inode(c, ic)
+ * is used to force xattr data integrity check during the initial gc scan.
+ * -------------------------------------------------- */
+static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+ struct jffs2_eraseblock *jeb;
+ struct jffs2_raw_node_ref *raw;
+ struct jffs2_raw_xref rr;
+ size_t readlen;
+ uint32_t crc, offset, totlen;
+ int rc;
+
+ spin_lock(&c->erase_completion_lock);
+ if (ref_flags(ref->node) != REF_UNCHECKED)
+ goto complete;
+ offset = ref_offset(ref->node);
+ spin_unlock(&c->erase_completion_lock);
+
+ rc = jffs2_flash_read(c, offset, 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, offset);
+ return rc ? rc : -EIO;
+ }
+ /* obsolete node */
+ crc = crc32(0, &rr, sizeof(rr) - 4);
+ if (crc != je32_to_cpu(rr.node_crc)) {
+ JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+ offset, je32_to_cpu(rr.node_crc), crc);
+ return JFFS2_XATTR_IS_CORRUPTED;
+ }
+ 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",
+ offset, 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 JFFS2_XATTR_IS_CORRUPTED;
+ }
+ ref->ino = je32_to_cpu(rr.ino);
+ ref->xid = je32_to_cpu(rr.xid);
+ ref->xseqno = je32_to_cpu(rr.xseqno);
+ if (ref->xseqno > c->highest_xseqno)
+ c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
+
+ spin_lock(&c->erase_completion_lock);
+ complete:
+ for (raw=ref->node; raw != (void *)ref; raw=raw->next_in_ino) {
+ jeb = &c->blocks[ref_offset(raw) / c->sector_size];
+ totlen = PAD(ref_totlen(c, jeb, raw));
+ if (ref_flags(raw) == REF_UNCHECKED) {
+ c->unchecked_size -= totlen; c->used_size += totlen;
+ jeb->unchecked_size -= totlen; jeb->used_size += totlen;
+ }
+ raw->flash_offset = ref_offset(raw) | ((ref->node==raw) ? REF_PRISTINE : REF_NORMAL);
+ }
+ 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 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_xref rr;
+ size_t length;
+ uint32_t xseqno, 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));
+
+ xseqno = (c->highest_xseqno += 2);
+ if (is_xattr_ref_dead(ref)) {
+ xseqno |= XREF_DELETE_MARKER;
+ rr.ino = cpu_to_je32(ref->ino);
+ rr.xid = cpu_to_je32(ref->xid);
+ } else {
+ rr.ino = cpu_to_je32(ref->ic->ino);
+ rr.xid = cpu_to_je32(ref->xd->xid);
+ }
+ rr.xseqno = cpu_to_je32(xseqno);
+ 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;
+ }
+ /* success */
+ ref->xseqno = xseqno;
+ jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), (void *)ref);
+
+ 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 */
+}
+
+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;
+
+ xd = ref->xd;
+ ref->xseqno |= XREF_DELETE_MARKER;
+ ref->ino = ref->ic->ino;
+ ref->xid = ref->xd->xid;
+ spin_lock(&c->erase_completion_lock);
+ ref->next = c->xref_dead_list;
+ c->xref_dead_list = ref;
+ spin_unlock(&c->erase_completion_lock);
+
+ dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) was removed.\n",
+ ref->ino, ref->xid, ref->xseqno);
+
+ unrefer_xattr_datum(c, xd);
+}
+
+void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+ /* It's called from jffs2_evict_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->pino_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;
+ if (atomic_dec_and_test(&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 that 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, **pcmp;
+ 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, pcmp=&ref->next; cmp; pcmp=&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)) {
+ *pcmp = 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)) {
+ if (ref->xseqno > cmp->xseqno) {
+ *pcmp = cmp->next;
+ delete_xattr_ref(c, cmp);
+ } else {
+ *pref = ref->next;
+ delete_xattr_ref(c, ref);
+ }
+ goto retry;
+ }
+ }
+ }
+ ic->flags |= INO_FLAGS_XATTR_CHECKED;
+ out:
+ up_write(&c->xattr_sem);
+
+ return rc;
+}
+
+void jffs2_xattr_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+ check_xattr_ref_inode(c, ic);
+}
+
+/* -------- 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);
+ INIT_LIST_HEAD(&c->xattr_dead_list);
+ c->xref_dead_list = NULL;
+ c->xref_temp = NULL;
+
+ init_rwsem(&c->xattr_sem);
+ c->highest_xid = 0;
+ c->highest_xseqno = 0;
+ 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);
+ }
+
+ for (ref=c->xref_dead_list; ref; ref = _ref) {
+ _ref = ref->next;
+ jffs2_free_xattr_ref(ref);
+ }
+
+ for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
+ list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
+ list_del(&xd->xindex);
+ kfree(xd->xname);
+ jffs2_free_xattr_datum(xd);
+ }
+ }
+
+ list_for_each_entry_safe(xd, _xd, &c->xattr_dead_list, xindex) {
+ list_del(&xd->xindex);
+ jffs2_free_xattr_datum(xd);
+ }
+ list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
+ list_del(&xd->xindex);
+ jffs2_free_xattr_datum(xd);
+ }
+}
+
+#define XREF_TMPHASH_SIZE (128)
+int jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
+{
+ struct jffs2_xattr_ref *ref, *_ref;
+ struct jffs2_xattr_ref **xref_tmphash;
+ struct jffs2_xattr_datum *xd, *_xd;
+ struct jffs2_inode_cache *ic;
+ struct jffs2_raw_node_ref *raw;
+ int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
+ int xdatum_orphan_count = 0, xref_orphan_count = 0, xref_dead_count = 0;
+
+ BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
+
+ xref_tmphash = kcalloc(XREF_TMPHASH_SIZE,
+ sizeof(struct jffs2_xattr_ref *), GFP_KERNEL);
+ if (!xref_tmphash)
+ return -ENOMEM;
+
+ /* Phase.1 : Merge same xref */
+ for (ref=c->xref_temp; ref; ref=_ref) {
+ struct jffs2_xattr_ref *tmp;
+
+ _ref = ref->next;
+ if (ref_flags(ref->node) != REF_PRISTINE) {
+ if (verify_xattr_ref(c, ref)) {
+ BUG_ON(ref->node->next_in_ino != (void *)ref);
+ ref->node->next_in_ino = NULL;
+ jffs2_mark_node_obsolete(c, ref->node);
+ jffs2_free_xattr_ref(ref);
+ continue;
+ }
+ }
+
+ i = (ref->ino ^ ref->xid) % XREF_TMPHASH_SIZE;
+ for (tmp=xref_tmphash[i]; tmp; tmp=tmp->next) {
+ if (tmp->ino == ref->ino && tmp->xid == ref->xid)
+ break;
+ }
+ if (tmp) {
+ raw = ref->node;
+ if (ref->xseqno > tmp->xseqno) {
+ tmp->xseqno = ref->xseqno;
+ raw->next_in_ino = tmp->node;
+ tmp->node = raw;
+ } else {
+ raw->next_in_ino = tmp->node->next_in_ino;
+ tmp->node->next_in_ino = raw;
+ }
+ jffs2_free_xattr_ref(ref);
+ continue;
+ } else {
+ ref->next = xref_tmphash[i];
+ xref_tmphash[i] = ref;
+ }
+ }
+ c->xref_temp = NULL;
+
+ /* Phase.2 : Bind xref with inode_cache and xattr_datum */
+ for (i=0; i < XREF_TMPHASH_SIZE; i++) {
+ for (ref=xref_tmphash[i]; ref; ref=_ref) {
+ xref_count++;
+ _ref = ref->next;
+ if (is_xattr_ref_dead(ref)) {
+ ref->next = c->xref_dead_list;
+ c->xref_dead_list = ref;
+ xref_dead_count++;
+ 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 || !ic->pino_nlink) {
+ dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n",
+ ref->ino, ref->xid, ref->xseqno);
+ ref->xseqno |= XREF_DELETE_MARKER;
+ ref->next = c->xref_dead_list;
+ c->xref_dead_list = ref;
+ xref_orphan_count++;
+ continue;
+ }
+ ref->xd = xd;
+ ref->ic = ic;
+ atomic_inc(&xd->refcnt);
+ ref->next = ic->xref;
+ ic->xref = ref;
+ }
+ }
+
+ /* Phase.3 : Link unchecked xdatum to xattr_unchecked list */
+ for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
+ list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
+ xdatum_count++;
+ list_del_init(&xd->xindex);
+ if (!atomic_read(&xd->refcnt)) {
+ dbg_xattr("xdatum(xid=%u, version=%u) is orphan.\n",
+ xd->xid, xd->version);
+ xd->flags |= JFFS2_XFLAGS_DEAD;
+ list_add(&xd->xindex, &c->xattr_unchecked);
+ xdatum_orphan_count++;
+ continue;
+ }
+ if (is_xattr_datum_unchecked(c, xd)) {
+ dbg_xattr("unchecked xdatum(xid=%u, version=%u)\n",
+ xd->xid, xd->version);
+ list_add(&xd->xindex, &c->xattr_unchecked);
+ xdatum_unchecked_count++;
+ }
+ }
+ }
+ /* build complete */
+ JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum"
+ " (%u unchecked, %u orphan) and "
+ "%u of xref (%u dead, %u orphan) found.\n",
+ xdatum_count, xdatum_unchecked_count, xdatum_orphan_count,
+ xref_count, xref_dead_count, xref_orphan_count);
+ kfree(xref_tmphash);
+ return 0;
+}
+
+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 = jffs2_find_xattr_datum(c, xid);
+ if (!xd) {
+ 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]);
+ }
+ 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.
+ * -------------------------------------------------- */
+const 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
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+#endif
+ &jffs2_trusted_xattr_handler,
+ NULL
+};
+
+static const struct xattr_handler *xprefix_to_handler(int xprefix) {
+ const 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 = &posix_acl_access_xattr_handler;
+ break;
+ case JFFS2_XPREFIX_ACL_DEFAULT:
+ ret = &posix_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 = d_inode(dentry);
+ 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;
+ const struct xattr_handler *xhandle;
+ const char *prefix;
+ ssize_t prefix_len, 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 || (xhandle->list && !xhandle->list(dentry)))
+ continue;
+ prefix = xhandle->prefix ?: xhandle->name;
+ prefix_len = strlen(prefix);
+ rc = prefix_len + xd->name_len + 1;
+
+ if (buffer) {
+ if (rc > size - len) {
+ rc = -ERANGE;
+ goto out;
+ }
+ memcpy(buffer, prefix, prefix_len);
+ buffer += prefix_len;
+ memcpy(buffer, xd->xname, xd->name_len);
+ buffer += xd->name_len;
+ *buffer++ = 0;
+ }
+ 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) {
+ ref->ino = ic->ino;
+ ref->xid = xd->xid;
+ ref->xseqno |= XREF_DELETE_MARKER;
+ rc = save_xattr_ref(c, ref);
+ if (!rc) {
+ *pref = ref->next;
+ spin_lock(&c->erase_completion_lock);
+ ref->next = c->xref_dead_list;
+ c->xref_dead_list = ref;
+ spin_unlock(&c->erase_completion_lock);
+ unrefer_xattr_datum(c, xd);
+ } else {
+ ref->ic = ic;
+ ref->xd = xd;
+ ref->xseqno &= ~XREF_DELETE_MARKER;
+ }
+ goto out;
+ }
+ goto found;
+ }
+ }
+ /* not found */
+ if (flags & XATTR_REPLACE) {
+ rc = -ENODATA;
+ goto out;
+ }
+ if (!buffer) {
+ rc = -ENODATA;
+ 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);
+ down_write(&c->xattr_sem);
+ if (rc) {
+ JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
+ unrefer_xattr_datum(c, xd);
+ up_write(&c->xattr_sem);
+ return rc;
+ }
+ 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);
+ unrefer_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, raw)
+ * is used to move xdatum into new node.
+ * jffs2_garbage_collect_xattr_ref(c, ref, raw)
+ * is used to move xref into new node.
+ * jffs2_verify_xattr(c)
+ * is used to call do_verify_xattr_datum() before garbage collecting.
+ * jffs2_release_xattr_datum(c, xd)
+ * is used to release an in-memory object of xdatum.
+ * jffs2_release_xattr_ref(c, ref)
+ * is used to release an in-memory object of xref.
+ * -------------------------------------------------- */
+int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
+ struct jffs2_raw_node_ref *raw)
+{
+ uint32_t totlen, length, old_ofs;
+ int rc = 0;
+
+ down_write(&c->xattr_sem);
+ if (xd->node != raw)
+ goto out;
+ if (xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID))
+ goto out;
+
+ rc = load_xattr_datum(c, xd);
+ if (unlikely(rc)) {
+ rc = (rc > 0) ? 0 : rc;
+ goto out;
+ }
+ old_ofs = ref_offset(xd->node);
+ totlen = PAD(sizeof(struct jffs2_raw_xattr)
+ + xd->name_len + 1 + xd->value_len);
+ rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
+ if (rc) {
+ JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
+ 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:
+ if (!rc)
+ jffs2_mark_node_obsolete(c, raw);
+ up_write(&c->xattr_sem);
+ return rc;
+}
+
+int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
+ struct jffs2_raw_node_ref *raw)
+{
+ uint32_t totlen, length, old_ofs;
+ int rc = 0;
+
+ down_write(&c->xattr_sem);
+ BUG_ON(!ref->node);
+
+ if (ref->node != raw)
+ goto out;
+ if (is_xattr_ref_dead(ref) && (raw->next_in_ino == (void *)ref))
+ goto out;
+
+ old_ofs = ref_offset(ref->node);
+ totlen = ref_totlen(c, c->gcblock, ref->node);
+
+ rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XREF_SIZE);
+ if (rc) {
+ JFFS2_WARNING("%s: jffs2_reserve_space_gc() = %d, request = %u\n",
+ __func__, rc, totlen);
+ 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:
+ if (!rc)
+ jffs2_mark_node_obsolete(c, raw);
+ up_write(&c->xattr_sem);
+ return rc;
+}
+
+int jffs2_verify_xattr(struct jffs2_sb_info *c)
+{
+ struct jffs2_xattr_datum *xd, *_xd;
+ struct jffs2_eraseblock *jeb;
+ struct jffs2_raw_node_ref *raw;
+ uint32_t totlen;
+ 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)
+ continue;
+ list_del_init(&xd->xindex);
+ spin_lock(&c->erase_completion_lock);
+ for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
+ if (ref_flags(raw) != REF_UNCHECKED)
+ continue;
+ jeb = &c->blocks[ref_offset(raw) / c->sector_size];
+ totlen = PAD(ref_totlen(c, jeb, raw));
+ c->unchecked_size -= totlen; c->used_size += totlen;
+ jeb->unchecked_size -= totlen; jeb->used_size += totlen;
+ raw->flash_offset = ref_offset(raw)
+ | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
+ }
+ if (xd->flags & JFFS2_XFLAGS_DEAD)
+ list_add(&xd->xindex, &c->xattr_dead_list);
+ spin_unlock(&c->erase_completion_lock);
+ }
+ up_write(&c->xattr_sem);
+ return list_empty(&c->xattr_unchecked) ? 1 : 0;
+}
+
+void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+ /* must be called under spin_lock(&c->erase_completion_lock) */
+ if (atomic_read(&xd->refcnt) || xd->node != (void *)xd)
+ return;
+
+ list_del(&xd->xindex);
+ jffs2_free_xattr_datum(xd);
+}
+
+void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+ /* must be called under spin_lock(&c->erase_completion_lock) */
+ struct jffs2_xattr_ref *tmp, **ptmp;
+
+ if (ref->node != (void *)ref)
+ return;
+
+ for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
+ if (ref == tmp) {
+ *ptmp = tmp->next;
+ break;
+ }
+ }
+ jffs2_free_xattr_ref(ref);
+}