diff options
Diffstat (limited to 'fs/jffs2/xattr.c')
| -rw-r--r-- | fs/jffs2/xattr.c | 1238 |
1 files changed, 1238 insertions, 0 deletions
diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c new file mode 100644 index 00000000000..2d82e250be3 --- /dev/null +++ b/fs/jffs2/xattr.c @@ -0,0 +1,1238 @@ +/* + * 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 = ℞ + 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; +} |