xattr.c

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/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License version 2.
 */

#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/xattr.h>
#include <linux/gfs2_ondisk.h>
#include <asm/uaccess.h>

#include "gfs2.h"
#include "incore.h"
#include "acl.h"
#include "xattr.h"
#include "glock.h"
#include "inode.h"
#include "meta_io.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"

static int ea_calc_size(struct gfs2_sbd *sdp, unsigned int nsize, size_t dsize,
            unsigned int *size)
{
    unsigned int jbsize = sdp->sd_jbsize;

    /* Stuffed */
    *size = ALIGN(sizeof(struct gfs2_ea_header) + nsize + dsize, 8);

    if (*size <= jbsize)
        return 1;

    /* Unstuffed */
    *size = ALIGN(sizeof(struct gfs2_ea_header) + nsize +
              (sizeof(__be64) * DIV_ROUND_UP(dsize, jbsize)), 8);

    return 0;
}

static int ea_check_size(struct gfs2_sbd *sdp, unsigned int nsize, size_t dsize)
{
    unsigned int size;

    if (dsize > GFS2_EA_MAX_DATA_LEN)
        return -ERANGE;

    ea_calc_size(sdp, nsize, dsize, &size);

    /* This can only happen with 512 byte blocks */
    if (size > sdp->sd_jbsize)
        return -ERANGE;

    return 0;
}

typedef int (*ea_call_t) (struct gfs2_inode *ip, struct buffer_head *bh,
              struct gfs2_ea_header *ea,
              struct gfs2_ea_header *prev, void *private);

static int ea_foreach_i(struct gfs2_inode *ip, struct buffer_head *bh,
            ea_call_t ea_call, void *data)
{
    struct gfs2_ea_header *ea, *prev = NULL;
    int error = 0;

    if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_EA))
        return -EIO;

    for (ea = GFS2_EA_BH2FIRST(bh);; prev = ea, ea = GFS2_EA2NEXT(ea)) {
        if (!GFS2_EA_REC_LEN(ea))
            goto fail;
        if (!(bh->b_data <= (char *)ea && (char *)GFS2_EA2NEXT(ea) <=
                          bh->b_data + bh->b_size))
            goto fail;
        if (!GFS2_EATYPE_VALID(ea->ea_type))
            goto fail;

        error = ea_call(ip, bh, ea, prev, data);
        if (error)
            return error;

        if (GFS2_EA_IS_LAST(ea)) {
            if ((char *)GFS2_EA2NEXT(ea) !=
                bh->b_data + bh->b_size)
                goto fail;
            break;
        }
    }

    return error;

fail:
    gfs2_consist_inode(ip);
    return -EIO;
}

static int ea_foreach(struct gfs2_inode *ip, ea_call_t ea_call, void *data)
{
    struct buffer_head *bh, *eabh;
    __be64 *eablk, *end;
    int error;

    error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, &bh);
    if (error)
        return error;

    if (!(ip->i_diskflags & GFS2_DIF_EA_INDIRECT)) {
        error = ea_foreach_i(ip, bh, ea_call, data);
        goto out;
    }

    if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_IN)) {
        error = -EIO;
        goto out;
    }

    eablk = (__be64 *)(bh->b_data + sizeof(struct gfs2_meta_header));
    end = eablk + GFS2_SB(&ip->i_inode)->sd_inptrs;

    for (; eablk < end; eablk++) {
        u64 bn;

        if (!*eablk)
            break;
        bn = be64_to_cpu(*eablk);

        error = gfs2_meta_read(ip->i_gl, bn, DIO_WAIT, &eabh);
        if (error)
            break;
        error = ea_foreach_i(ip, eabh, ea_call, data);
        brelse(eabh);
        if (error)
            break;
    }
out:
    brelse(bh);
    return error;
}

struct ea_find {
    int type;
    const char *name;
    size_t namel;
    struct gfs2_ea_location *ef_el;
};

static int ea_find_i(struct gfs2_inode *ip, struct buffer_head *bh,
             struct gfs2_ea_header *ea, struct gfs2_ea_header *prev,
             void *private)
{
    struct ea_find *ef = private;

    if (ea->ea_type == GFS2_EATYPE_UNUSED)
        return 0;

    if (ea->ea_type == ef->type) {
        if (ea->ea_name_len == ef->namel &&
            !memcmp(GFS2_EA2NAME(ea), ef->name, ea->ea_name_len)) {
            struct gfs2_ea_location *el = ef->ef_el;
            get_bh(bh);
            el->el_bh = bh;
            el->el_ea = ea;
            el->el_prev = prev;
            return 1;
        }
    }

    return 0;
}

static int gfs2_ea_find(struct gfs2_inode *ip, int type, const char *name,
            struct gfs2_ea_location *el)
{
    struct ea_find ef;
    int error;

    ef.type = type;
    ef.name = name;
    ef.namel = strlen(name);
    ef.ef_el = el;

    memset(el, 0, sizeof(struct gfs2_ea_location));

    error = ea_foreach(ip, ea_find_i, &ef);
    if (error > 0)
        return 0;

    return error;
}

static int ea_dealloc_unstuffed(struct gfs2_inode *ip, struct buffer_head *bh,
                struct gfs2_ea_header *ea,
                struct gfs2_ea_header *prev, void *private)
{
    int *leave = private;
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct gfs2_rgrpd *rgd;
    struct gfs2_holder rg_gh;
    struct buffer_head *dibh;
    __be64 *dataptrs;
    u64 bn = 0;
    u64 bstart = 0;
    unsigned int blen = 0;
    unsigned int blks = 0;
    unsigned int x;
    int error;

    error = gfs2_rindex_update(sdp);
    if (error)
        return error;

    if (GFS2_EA_IS_STUFFED(ea))
        return 0;

    dataptrs = GFS2_EA2DATAPTRS(ea);
    for (x = 0; x < ea->ea_num_ptrs; x++, dataptrs++) {
        if (*dataptrs) {
            blks++;
            bn = be64_to_cpu(*dataptrs);
        }
    }
    if (!blks)
        return 0;

    rgd = gfs2_blk2rgrpd(sdp, bn, 1);
    if (!rgd) {
        gfs2_consist_inode(ip);
        return -EIO;
    }

    error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &rg_gh);
    if (error)
        return error;

    error = gfs2_trans_begin(sdp, rgd->rd_length + RES_DINODE +
                 RES_EATTR + RES_STATFS + RES_QUOTA, blks);
    if (error)
        goto out_gunlock;

    gfs2_trans_add_bh(ip->i_gl, bh, 1);

    dataptrs = GFS2_EA2DATAPTRS(ea);
    for (x = 0; x < ea->ea_num_ptrs; x++, dataptrs++) {
        if (!*dataptrs)
            break;
        bn = be64_to_cpu(*dataptrs);

        if (bstart + blen == bn)
            blen++;
        else {
            if (bstart)
                gfs2_free_meta(ip, bstart, blen);
            bstart = bn;
            blen = 1;
        }

        *dataptrs = 0;
        gfs2_add_inode_blocks(&ip->i_inode, -1);
    }
    if (bstart)
        gfs2_free_meta(ip, bstart, blen);

    if (prev && !leave) {
        u32 len;

        len = GFS2_EA_REC_LEN(prev) + GFS2_EA_REC_LEN(ea);
        prev->ea_rec_len = cpu_to_be32(len);

        if (GFS2_EA_IS_LAST(ea))
            prev->ea_flags |= GFS2_EAFLAG_LAST;
    } else {
        ea->ea_type = GFS2_EATYPE_UNUSED;
        ea->ea_num_ptrs = 0;
    }

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (!error) {
        ip->i_inode.i_ctime = CURRENT_TIME;
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
        gfs2_dinode_out(ip, dibh->b_data);
        brelse(dibh);
    }

    gfs2_trans_end(sdp);

out_gunlock:
    gfs2_glock_dq_uninit(&rg_gh);
    return error;
}

static int ea_remove_unstuffed(struct gfs2_inode *ip, struct buffer_head *bh,
                   struct gfs2_ea_header *ea,
                   struct gfs2_ea_header *prev, int leave)
{
    int error;

    error = gfs2_rindex_update(GFS2_SB(&ip->i_inode));
    if (error)
        return error;

    error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
    if (error)
        goto out_alloc;

    error = ea_dealloc_unstuffed(ip, bh, ea, prev, (leave) ? &error : NULL);

    gfs2_quota_unhold(ip);
out_alloc:
    return error;
}

struct ea_list {
    struct gfs2_ea_request *ei_er;
    unsigned int ei_size;
};

static inline unsigned int gfs2_ea_strlen(struct gfs2_ea_header *ea)
{
    switch (ea->ea_type) {
    case GFS2_EATYPE_USR:
        return 5 + ea->ea_name_len + 1;
    case GFS2_EATYPE_SYS:
        return 7 + ea->ea_name_len + 1;
    case GFS2_EATYPE_SECURITY:
        return 9 + ea->ea_name_len + 1;
    default:
        return 0;
    }
}

static int ea_list_i(struct gfs2_inode *ip, struct buffer_head *bh,
             struct gfs2_ea_header *ea, struct gfs2_ea_header *prev,
             void *private)
{
    struct ea_list *ei = private;
    struct gfs2_ea_request *er = ei->ei_er;
    unsigned int ea_size = gfs2_ea_strlen(ea);

    if (ea->ea_type == GFS2_EATYPE_UNUSED)
        return 0;

    if (er->er_data_len) {
        char *prefix = NULL;
        unsigned int l = 0;
        char c = 0;

        if (ei->ei_size + ea_size > er->er_data_len)
            return -ERANGE;

        switch (ea->ea_type) {
        case GFS2_EATYPE_USR:
            prefix = "user.";
            l = 5;
            break;
        case GFS2_EATYPE_SYS:
            prefix = "system.";
            l = 7;
            break;
        case GFS2_EATYPE_SECURITY:
            prefix = "security.";
            l = 9;
            break;
        }

        BUG_ON(l == 0);

        memcpy(er->er_data + ei->ei_size, prefix, l);
        memcpy(er->er_data + ei->ei_size + l, GFS2_EA2NAME(ea),
               ea->ea_name_len);
        memcpy(er->er_data + ei->ei_size + ea_size - 1, &c, 1);
    }

    ei->ei_size += ea_size;

    return 0;
}

ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
    struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
    struct gfs2_ea_request er;
    struct gfs2_holder i_gh;
    int error;

    memset(&er, 0, sizeof(struct gfs2_ea_request));
    if (size) {
        er.er_data = buffer;
        er.er_data_len = size;
    }

    error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
    if (error)
        return error;

    if (ip->i_eattr) {
        struct ea_list ei = { .ei_er = &er, .ei_size = 0 };

        error = ea_foreach(ip, ea_list_i, &ei);
        if (!error)
            error = ei.ei_size;
    }

    gfs2_glock_dq_uninit(&i_gh);

    return error;
}

static int gfs2_iter_unstuffed(struct gfs2_inode *ip, struct gfs2_ea_header *ea,
                   const char *din, char *dout)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct buffer_head **bh;
    unsigned int amount = GFS2_EA_DATA_LEN(ea);
    unsigned int nptrs = DIV_ROUND_UP(amount, sdp->sd_jbsize);
    __be64 *dataptrs = GFS2_EA2DATAPTRS(ea);
    unsigned int x;
    int error = 0;
    unsigned char *pos;
    unsigned cp_size;

    bh = kcalloc(nptrs, sizeof(struct buffer_head *), GFP_NOFS);
    if (!bh)
        return -ENOMEM;

    for (x = 0; x < nptrs; x++) {
        error = gfs2_meta_read(ip->i_gl, be64_to_cpu(*dataptrs), 0,
                       bh + x);
        if (error) {
            while (x--)
                brelse(bh[x]);
            goto out;
        }
        dataptrs++;
    }

    for (x = 0; x < nptrs; x++) {
        error = gfs2_meta_wait(sdp, bh[x]);
        if (error) {
            for (; x < nptrs; x++)
                brelse(bh[x]);
            goto out;
        }
        if (gfs2_metatype_check(sdp, bh[x], GFS2_METATYPE_ED)) {
            for (; x < nptrs; x++)
                brelse(bh[x]);
            error = -EIO;
            goto out;
        }

        pos = bh[x]->b_data + sizeof(struct gfs2_meta_header);
        cp_size = (sdp->sd_jbsize > amount) ? amount : sdp->sd_jbsize;

        if (dout) {
            memcpy(dout, pos, cp_size);
            dout += sdp->sd_jbsize;
        }

        if (din) {
            gfs2_trans_add_bh(ip->i_gl, bh[x], 1);
            memcpy(pos, din, cp_size);
            din += sdp->sd_jbsize;
        }

        amount -= sdp->sd_jbsize;
        brelse(bh[x]);
    }

out:
    kfree(bh);
    return error;
}

static int gfs2_ea_get_copy(struct gfs2_inode *ip, struct gfs2_ea_location *el,
                char *data, size_t size)
{
    int ret;
    size_t len = GFS2_EA_DATA_LEN(el->el_ea);
    if (len > size)
        return -ERANGE;

    if (GFS2_EA_IS_STUFFED(el->el_ea)) {
        memcpy(data, GFS2_EA2DATA(el->el_ea), len);
        return len;
    }
    ret = gfs2_iter_unstuffed(ip, el->el_ea, NULL, data);
    if (ret < 0)
        return ret;
    return len;
}

int gfs2_xattr_acl_get(struct gfs2_inode *ip, const char *name, char **ppdata)
{
    struct gfs2_ea_location el;
    int error;
    int len;
    char *data;

    error = gfs2_ea_find(ip, GFS2_EATYPE_SYS, name, &el);
    if (error)
        return error;
    if (!el.el_ea)
        goto out;
    if (!GFS2_EA_DATA_LEN(el.el_ea))
        goto out;

    len = GFS2_EA_DATA_LEN(el.el_ea);
    data = kmalloc(len, GFP_NOFS);
    error = -ENOMEM;
    if (data == NULL)
        goto out;

    error = gfs2_ea_get_copy(ip, &el, data, len);
    if (error < 0)
        kfree(data);
    else
        *ppdata = data;
out:
    brelse(el.el_bh);
    return error;
}

static int gfs2_xattr_get(struct dentry *dentry, const char *name,
        void *buffer, size_t size, int type)
{
    struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
    struct gfs2_ea_location el;
    int error;

    if (!ip->i_eattr)
        return -ENODATA;
    if (strlen(name) > GFS2_EA_MAX_NAME_LEN)
        return -EINVAL;

    error = gfs2_ea_find(ip, type, name, &el);
    if (error)
        return error;
    if (!el.el_ea)
        return -ENODATA;
    if (size)
        error = gfs2_ea_get_copy(ip, &el, buffer, size);
    else
        error = GFS2_EA_DATA_LEN(el.el_ea);
    brelse(el.el_bh);

    return error;
}

static int ea_alloc_blk(struct gfs2_inode *ip, struct buffer_head **bhp)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct gfs2_ea_header *ea;
    unsigned int n = 1;
    u64 block;
    int error;

    error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL);
    if (error)
        return error;
    gfs2_trans_add_unrevoke(sdp, block, 1);
    *bhp = gfs2_meta_new(ip->i_gl, block);
    gfs2_trans_add_bh(ip->i_gl, *bhp, 1);
    gfs2_metatype_set(*bhp, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
    gfs2_buffer_clear_tail(*bhp, sizeof(struct gfs2_meta_header));

    ea = GFS2_EA_BH2FIRST(*bhp);
    ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
    ea->ea_type = GFS2_EATYPE_UNUSED;
    ea->ea_flags = GFS2_EAFLAG_LAST;
    ea->ea_num_ptrs = 0;

    gfs2_add_inode_blocks(&ip->i_inode, 1);

    return 0;
}

static int ea_write(struct gfs2_inode *ip, struct gfs2_ea_header *ea,
            struct gfs2_ea_request *er)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    int error;

    ea->ea_data_len = cpu_to_be32(er->er_data_len);
    ea->ea_name_len = er->er_name_len;
    ea->ea_type = er->er_type;
    ea->__pad = 0;

    memcpy(GFS2_EA2NAME(ea), er->er_name, er->er_name_len);

    if (GFS2_EAREQ_SIZE_STUFFED(er) <= sdp->sd_jbsize) {
        ea->ea_num_ptrs = 0;
        memcpy(GFS2_EA2DATA(ea), er->er_data, er->er_data_len);
    } else {
        __be64 *dataptr = GFS2_EA2DATAPTRS(ea);
        const char *data = er->er_data;
        unsigned int data_len = er->er_data_len;
        unsigned int copy;
        unsigned int x;

        ea->ea_num_ptrs = DIV_ROUND_UP(er->er_data_len, sdp->sd_jbsize);
        for (x = 0; x < ea->ea_num_ptrs; x++) {
            struct buffer_head *bh;
            u64 block;
            int mh_size = sizeof(struct gfs2_meta_header);
            unsigned int n = 1;

            error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL);
            if (error)
                return error;
            gfs2_trans_add_unrevoke(sdp, block, 1);
            bh = gfs2_meta_new(ip->i_gl, block);
            gfs2_trans_add_bh(ip->i_gl, bh, 1);
            gfs2_metatype_set(bh, GFS2_METATYPE_ED, GFS2_FORMAT_ED);

            gfs2_add_inode_blocks(&ip->i_inode, 1);

            copy = data_len > sdp->sd_jbsize ? sdp->sd_jbsize :
                               data_len;
            memcpy(bh->b_data + mh_size, data, copy);
            if (copy < sdp->sd_jbsize)
                memset(bh->b_data + mh_size + copy, 0,
                       sdp->sd_jbsize - copy);

            *dataptr++ = cpu_to_be64(bh->b_blocknr);
            data += copy;
            data_len -= copy;

            brelse(bh);
        }

        gfs2_assert_withdraw(sdp, !data_len);
    }

    return 0;
}

typedef int (*ea_skeleton_call_t) (struct gfs2_inode *ip,
                   struct gfs2_ea_request *er, void *private);

static int ea_alloc_skeleton(struct gfs2_inode *ip, struct gfs2_ea_request *er,
                 unsigned int blks,
                 ea_skeleton_call_t skeleton_call, void *private)
{
    struct buffer_head *dibh;
    int error;

    error = gfs2_rindex_update(GFS2_SB(&ip->i_inode));
    if (error)
        return error;

    error = gfs2_quota_lock_check(ip);
    if (error)
        return error;

    error = gfs2_inplace_reserve(ip, blks);
    if (error)
        goto out_gunlock_q;

    error = gfs2_trans_begin(GFS2_SB(&ip->i_inode),
                 blks + gfs2_rg_blocks(ip, blks) +
                 RES_DINODE + RES_STATFS + RES_QUOTA, 0);
    if (error)
        goto out_ipres;

    error = skeleton_call(ip, er, private);
    if (error)
        goto out_end_trans;

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (!error) {
        ip->i_inode.i_ctime = CURRENT_TIME;
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
        gfs2_dinode_out(ip, dibh->b_data);
        brelse(dibh);
    }

out_end_trans:
    gfs2_trans_end(GFS2_SB(&ip->i_inode));
out_ipres:
    gfs2_inplace_release(ip);
out_gunlock_q:
    gfs2_quota_unlock(ip);
    return error;
}

static int ea_init_i(struct gfs2_inode *ip, struct gfs2_ea_request *er,
             void *private)
{
    struct buffer_head *bh;
    int error;

    error = ea_alloc_blk(ip, &bh);
    if (error)
        return error;

    ip->i_eattr = bh->b_blocknr;
    error = ea_write(ip, GFS2_EA_BH2FIRST(bh), er);

    brelse(bh);

    return error;
}

static int ea_init(struct gfs2_inode *ip, int type, const char *name,
           const void *data, size_t size)
{
    struct gfs2_ea_request er;
    unsigned int jbsize = GFS2_SB(&ip->i_inode)->sd_jbsize;
    unsigned int blks = 1;

    er.er_type = type;
    er.er_name = name;
    er.er_name_len = strlen(name);
    er.er_data = (void *)data;
    er.er_data_len = size;

    if (GFS2_EAREQ_SIZE_STUFFED(&er) > jbsize)
        blks += DIV_ROUND_UP(er.er_data_len, jbsize);

    return ea_alloc_skeleton(ip, &er, blks, ea_init_i, NULL);
}

static struct gfs2_ea_header *ea_split_ea(struct gfs2_ea_header *ea)
{
    u32 ea_size = GFS2_EA_SIZE(ea);
    struct gfs2_ea_header *new = (struct gfs2_ea_header *)((char *)ea +
                     ea_size);
    u32 new_size = GFS2_EA_REC_LEN(ea) - ea_size;
    int last = ea->ea_flags & GFS2_EAFLAG_LAST;

    ea->ea_rec_len = cpu_to_be32(ea_size);
    ea->ea_flags ^= last;

    new->ea_rec_len = cpu_to_be32(new_size);
    new->ea_flags = last;

    return new;
}

static void ea_set_remove_stuffed(struct gfs2_inode *ip,
                  struct gfs2_ea_location *el)
{
    struct gfs2_ea_header *ea = el->el_ea;
    struct gfs2_ea_header *prev = el->el_prev;
    u32 len;

    gfs2_trans_add_bh(ip->i_gl, el->el_bh, 1);

    if (!prev || !GFS2_EA_IS_STUFFED(ea)) {
        ea->ea_type = GFS2_EATYPE_UNUSED;
        return;
    } else if (GFS2_EA2NEXT(prev) != ea) {
        prev = GFS2_EA2NEXT(prev);
        gfs2_assert_withdraw(GFS2_SB(&ip->i_inode), GFS2_EA2NEXT(prev) == ea);
    }

    len = GFS2_EA_REC_LEN(prev) + GFS2_EA_REC_LEN(ea);
    prev->ea_rec_len = cpu_to_be32(len);

    if (GFS2_EA_IS_LAST(ea))
        prev->ea_flags |= GFS2_EAFLAG_LAST;
}

struct ea_set {
    int ea_split;

    struct gfs2_ea_request *es_er;
    struct gfs2_ea_location *es_el;

    struct buffer_head *es_bh;
    struct gfs2_ea_header *es_ea;
};

static int ea_set_simple_noalloc(struct gfs2_inode *ip, struct buffer_head *bh,
                 struct gfs2_ea_header *ea, struct ea_set *es)
{
    struct gfs2_ea_request *er = es->es_er;
    struct buffer_head *dibh;
    int error;

    error = gfs2_trans_begin(GFS2_SB(&ip->i_inode), RES_DINODE + 2 * RES_EATTR, 0);
    if (error)
        return error;

    gfs2_trans_add_bh(ip->i_gl, bh, 1);

    if (es->ea_split)
        ea = ea_split_ea(ea);

    ea_write(ip, ea, er);

    if (es->es_el)
        ea_set_remove_stuffed(ip, es->es_el);

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (error)
        goto out;
    ip->i_inode.i_ctime = CURRENT_TIME;
    gfs2_trans_add_bh(ip->i_gl, dibh, 1);
    gfs2_dinode_out(ip, dibh->b_data);
    brelse(dibh);
out:
    gfs2_trans_end(GFS2_SB(&ip->i_inode));
    return error;
}

static int ea_set_simple_alloc(struct gfs2_inode *ip,
                   struct gfs2_ea_request *er, void *private)
{
    struct ea_set *es = private;
    struct gfs2_ea_header *ea = es->es_ea;
    int error;

    gfs2_trans_add_bh(ip->i_gl, es->es_bh, 1);

    if (es->ea_split)
        ea = ea_split_ea(ea);

    error = ea_write(ip, ea, er);
    if (error)
        return error;

    if (es->es_el)
        ea_set_remove_stuffed(ip, es->es_el);

    return 0;
}

static int ea_set_simple(struct gfs2_inode *ip, struct buffer_head *bh,
             struct gfs2_ea_header *ea, struct gfs2_ea_header *prev,
             void *private)
{
    struct ea_set *es = private;
    unsigned int size;
    int stuffed;
    int error;

    stuffed = ea_calc_size(GFS2_SB(&ip->i_inode), es->es_er->er_name_len,
                   es->es_er->er_data_len, &size);

    if (ea->ea_type == GFS2_EATYPE_UNUSED) {
        if (GFS2_EA_REC_LEN(ea) < size)
            return 0;
        if (!GFS2_EA_IS_STUFFED(ea)) {
            error = ea_remove_unstuffed(ip, bh, ea, prev, 1);
            if (error)
                return error;
        }
        es->ea_split = 0;
    } else if (GFS2_EA_REC_LEN(ea) - GFS2_EA_SIZE(ea) >= size)
        es->ea_split = 1;
    else
        return 0;

    if (stuffed) {
        error = ea_set_simple_noalloc(ip, bh, ea, es);
        if (error)
            return error;
    } else {
        unsigned int blks;

        es->es_bh = bh;
        es->es_ea = ea;
        blks = 2 + DIV_ROUND_UP(es->es_er->er_data_len,
                    GFS2_SB(&ip->i_inode)->sd_jbsize);

        error = ea_alloc_skeleton(ip, es->es_er, blks,
                      ea_set_simple_alloc, es);
        if (error)
            return error;
    }

    return 1;
}

static int ea_set_block(struct gfs2_inode *ip, struct gfs2_ea_request *er,
            void *private)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct buffer_head *indbh, *newbh;
    __be64 *eablk;
    int error;
    int mh_size = sizeof(struct gfs2_meta_header);

    if (ip->i_diskflags & GFS2_DIF_EA_INDIRECT) {
        __be64 *end;

        error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT,
                       &indbh);
        if (error)
            return error;

        if (gfs2_metatype_check(sdp, indbh, GFS2_METATYPE_IN)) {
            error = -EIO;
            goto out;
        }

        eablk = (__be64 *)(indbh->b_data + mh_size);
        end = eablk + sdp->sd_inptrs;

        for (; eablk < end; eablk++)
            if (!*eablk)
                break;

        if (eablk == end) {
            error = -ENOSPC;
            goto out;
        }

        gfs2_trans_add_bh(ip->i_gl, indbh, 1);
    } else {
        u64 blk;
        unsigned int n = 1;
        error = gfs2_alloc_blocks(ip, &blk, &n, 0, NULL);
        if (error)
            return error;
        gfs2_trans_add_unrevoke(sdp, blk, 1);
        indbh = gfs2_meta_new(ip->i_gl, blk);
        gfs2_trans_add_bh(ip->i_gl, indbh, 1);
        gfs2_metatype_set(indbh, GFS2_METATYPE_IN, GFS2_FORMAT_IN);
        gfs2_buffer_clear_tail(indbh, mh_size);

        eablk = (__be64 *)(indbh->b_data + mh_size);
        *eablk = cpu_to_be64(ip->i_eattr);
        ip->i_eattr = blk;
        ip->i_diskflags |= GFS2_DIF_EA_INDIRECT;
        gfs2_add_inode_blocks(&ip->i_inode, 1);

        eablk++;
    }

    error = ea_alloc_blk(ip, &newbh);
    if (error)
        goto out;

    *eablk = cpu_to_be64((u64)newbh->b_blocknr);
    error = ea_write(ip, GFS2_EA_BH2FIRST(newbh), er);
    brelse(newbh);
    if (error)
        goto out;

    if (private)
        ea_set_remove_stuffed(ip, private);

out:
    brelse(indbh);
    return error;
}

static int ea_set_i(struct gfs2_inode *ip, int type, const char *name,
            const void *value, size_t size, struct gfs2_ea_location *el)
{
    struct gfs2_ea_request er;
    struct ea_set es;
    unsigned int blks = 2;
    int error;

    er.er_type = type;
    er.er_name = name;
    er.er_data = (void *)value;
    er.er_name_len = strlen(name);
    er.er_data_len = size;

    memset(&es, 0, sizeof(struct ea_set));
    es.es_er = &er;
    es.es_el = el;

    error = ea_foreach(ip, ea_set_simple, &es);
    if (error > 0)
        return 0;
    if (error)
        return error;

    if (!(ip->i_diskflags & GFS2_DIF_EA_INDIRECT))
        blks++;
    if (GFS2_EAREQ_SIZE_STUFFED(&er) > GFS2_SB(&ip->i_inode)->sd_jbsize)
        blks += DIV_ROUND_UP(er.er_data_len, GFS2_SB(&ip->i_inode)->sd_jbsize);

    return ea_alloc_skeleton(ip, &er, blks, ea_set_block, el);
}

static int ea_set_remove_unstuffed(struct gfs2_inode *ip,
                   struct gfs2_ea_location *el)
{
    if (el->el_prev && GFS2_EA2NEXT(el->el_prev) != el->el_ea) {
        el->el_prev = GFS2_EA2NEXT(el->el_prev);
        gfs2_assert_withdraw(GFS2_SB(&ip->i_inode),
                     GFS2_EA2NEXT(el->el_prev) == el->el_ea);
    }

    return ea_remove_unstuffed(ip, el->el_bh, el->el_ea, el->el_prev, 0);
}

static int ea_remove_stuffed(struct gfs2_inode *ip, struct gfs2_ea_location *el)
{
    struct gfs2_ea_header *ea = el->el_ea;
    struct gfs2_ea_header *prev = el->el_prev;
    struct buffer_head *dibh;
    int error;

    error = gfs2_trans_begin(GFS2_SB(&ip->i_inode), RES_DINODE + RES_EATTR, 0);
    if (error)
        return error;

    gfs2_trans_add_bh(ip->i_gl, el->el_bh, 1);

    if (prev) {
        u32 len;

        len = GFS2_EA_REC_LEN(prev) + GFS2_EA_REC_LEN(ea);
        prev->ea_rec_len = cpu_to_be32(len);

        if (GFS2_EA_IS_LAST(ea))
            prev->ea_flags |= GFS2_EAFLAG_LAST;
    } else {
        ea->ea_type = GFS2_EATYPE_UNUSED;
    }

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (!error) {
        ip->i_inode.i_ctime = CURRENT_TIME;
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
        gfs2_dinode_out(ip, dibh->b_data);
        brelse(dibh);
    }

    gfs2_trans_end(GFS2_SB(&ip->i_inode));

    return error;
}

static int gfs2_xattr_remove(struct gfs2_inode *ip, int type, const char *name)
{
    struct gfs2_ea_location el;
    int error;

    if (!ip->i_eattr)
        return -ENODATA;

    error = gfs2_ea_find(ip, type, name, &el);
    if (error)
        return error;
    if (!el.el_ea)
        return -ENODATA;

    if (GFS2_EA_IS_STUFFED(el.el_ea))
        error = ea_remove_stuffed(ip, &el);
    else
        error = ea_remove_unstuffed(ip, el.el_bh, el.el_ea, el.el_prev, 0);

    brelse(el.el_bh);

    return error;
}

int __gfs2_xattr_set(struct inode *inode, const char *name,
           const void *value, size_t size, int flags, int type)
{
    struct gfs2_inode *ip = GFS2_I(inode);
    struct gfs2_sbd *sdp = GFS2_SB(inode);
    struct gfs2_ea_location el;
    unsigned int namel = strlen(name);
    int error;

    if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
        return -EPERM;
    if (namel > GFS2_EA_MAX_NAME_LEN)
        return -ERANGE;

    if (value == NULL)
        return gfs2_xattr_remove(ip, type, name);

    if (ea_check_size(sdp, namel, size))
        return -ERANGE;

    if (!ip->i_eattr) {
        if (flags & XATTR_REPLACE)
            return -ENODATA;
        return ea_init(ip, type, name, value, size);
    }

    error = gfs2_ea_find(ip, type, name, &el);
    if (error)
        return error;

    if (el.el_ea) {
        if (ip->i_diskflags & GFS2_DIF_APPENDONLY) {
            brelse(el.el_bh);
            return -EPERM;
        }

        error = -EEXIST;
        if (!(flags & XATTR_CREATE)) {
            int unstuffed = !GFS2_EA_IS_STUFFED(el.el_ea);
            error = ea_set_i(ip, type, name, value, size, &el);
            if (!error && unstuffed)
                ea_set_remove_unstuffed(ip, &el);
        }

        brelse(el.el_bh);
        return error;
    }

    error = -ENODATA;
    if (!(flags & XATTR_REPLACE))
        error = ea_set_i(ip, type, name, value, size, NULL);

    return error;
}

static int gfs2_xattr_set(struct dentry *dentry, const char *name,
        const void *value, size_t size, int flags, int type)
{
    return __gfs2_xattr_set(dentry->d_inode, name, value,
                size, flags, type);
}


static int ea_acl_chmod_unstuffed(struct gfs2_inode *ip,
                  struct gfs2_ea_header *ea, char *data)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    unsigned int amount = GFS2_EA_DATA_LEN(ea);
    unsigned int nptrs = DIV_ROUND_UP(amount, sdp->sd_jbsize);
    int ret;

    ret = gfs2_trans_begin(sdp, nptrs + RES_DINODE, 0);
    if (ret)
        return ret;

    ret = gfs2_iter_unstuffed(ip, ea, data, NULL);
    gfs2_trans_end(sdp);

    return ret;
}

int gfs2_xattr_acl_chmod(struct gfs2_inode *ip, struct iattr *attr, char *data)
{
    struct inode *inode = &ip->i_inode;
    struct gfs2_sbd *sdp = GFS2_SB(inode);
    struct gfs2_ea_location el;
    int error;

    error = gfs2_ea_find(ip, GFS2_EATYPE_SYS, GFS2_POSIX_ACL_ACCESS, &el);
    if (error)
        return error;

    if (GFS2_EA_IS_STUFFED(el.el_ea)) {
        error = gfs2_trans_begin(sdp, RES_DINODE + RES_EATTR, 0);
        if (error == 0) {
            gfs2_trans_add_bh(ip->i_gl, el.el_bh, 1);
            memcpy(GFS2_EA2DATA(el.el_ea), data,
                   GFS2_EA_DATA_LEN(el.el_ea));
        }
    } else {
        error = ea_acl_chmod_unstuffed(ip, el.el_ea, data);
    }

    brelse(el.el_bh);
    if (error)
        return error;

    error = gfs2_setattr_simple(inode, attr);
    gfs2_trans_end(sdp);
    return error;
}

static int ea_dealloc_indirect(struct gfs2_inode *ip)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct gfs2_rgrp_list rlist;
    struct buffer_head *indbh, *dibh;
    __be64 *eablk, *end;
    unsigned int rg_blocks = 0;
    u64 bstart = 0;
    unsigned int blen = 0;
    unsigned int blks = 0;
    unsigned int x;
    int error;

    error = gfs2_rindex_update(sdp);
    if (error)
        return error;

    memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));

    error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, &indbh);
    if (error)
        return error;

    if (gfs2_metatype_check(sdp, indbh, GFS2_METATYPE_IN)) {
        error = -EIO;
        goto out;
    }

    eablk = (__be64 *)(indbh->b_data + sizeof(struct gfs2_meta_header));
    end = eablk + sdp->sd_inptrs;

    for (; eablk < end; eablk++) {
        u64 bn;

        if (!*eablk)
            break;
        bn = be64_to_cpu(*eablk);

        if (bstart + blen == bn)
            blen++;
        else {
            if (bstart)
                gfs2_rlist_add(ip, &rlist, bstart);
            bstart = bn;
            blen = 1;
        }
        blks++;
    }
    if (bstart)
        gfs2_rlist_add(ip, &rlist, bstart);
    else
        goto out;

    gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);

    for (x = 0; x < rlist.rl_rgrps; x++) {
        struct gfs2_rgrpd *rgd;
        rgd = rlist.rl_ghs[x].gh_gl->gl_object;
        rg_blocks += rgd->rd_length;
    }

    error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
    if (error)
        goto out_rlist_free;

    error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE + RES_INDIRECT +
                 RES_STATFS + RES_QUOTA, blks);
    if (error)
        goto out_gunlock;

    gfs2_trans_add_bh(ip->i_gl, indbh, 1);

    eablk = (__be64 *)(indbh->b_data + sizeof(struct gfs2_meta_header));
    bstart = 0;
    blen = 0;

    for (; eablk < end; eablk++) {
        u64 bn;

        if (!*eablk)
            break;
        bn = be64_to_cpu(*eablk);

        if (bstart + blen == bn)
            blen++;
        else {
            if (bstart)
                gfs2_free_meta(ip, bstart, blen);
            bstart = bn;
            blen = 1;
        }

        *eablk = 0;
        gfs2_add_inode_blocks(&ip->i_inode, -1);
    }
    if (bstart)
        gfs2_free_meta(ip, bstart, blen);

    ip->i_diskflags &= ~GFS2_DIF_EA_INDIRECT;

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (!error) {
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
        gfs2_dinode_out(ip, dibh->b_data);
        brelse(dibh);
    }

    gfs2_trans_end(sdp);

out_gunlock:
    gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
out_rlist_free:
    gfs2_rlist_free(&rlist);
out:
    brelse(indbh);
    return error;
}

static int ea_dealloc_block(struct gfs2_inode *ip)
{
    struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
    struct gfs2_rgrpd *rgd;
    struct buffer_head *dibh;
    struct gfs2_holder gh;
    int error;

    error = gfs2_rindex_update(sdp);
    if (error)
        return error;

    rgd = gfs2_blk2rgrpd(sdp, ip->i_eattr, 1);
    if (!rgd) {
        gfs2_consist_inode(ip);
        return -EIO;
    }

    error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
    if (error)
        return error;

    error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_DINODE + RES_STATFS +
                 RES_QUOTA, 1);
    if (error)
        goto out_gunlock;

    gfs2_free_meta(ip, ip->i_eattr, 1);

    ip->i_eattr = 0;
    gfs2_add_inode_blocks(&ip->i_inode, -1);

    error = gfs2_meta_inode_buffer(ip, &dibh);
    if (!error) {
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
        gfs2_dinode_out(ip, dibh->b_data);
        brelse(dibh);
    }

    gfs2_trans_end(sdp);

out_gunlock:
    gfs2_glock_dq_uninit(&gh);
    return error;
}

int gfs2_ea_dealloc(struct gfs2_inode *ip)
{
    int error;

    error = gfs2_rindex_update(GFS2_SB(&ip->i_inode));
    if (error)
        return error;

    error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
    if (error)
        return error;

    error = ea_foreach(ip, ea_dealloc_unstuffed, NULL);
    if (error)
        goto out_quota;

    if (ip->i_diskflags & GFS2_DIF_EA_INDIRECT) {
        error = ea_dealloc_indirect(ip);
        if (error)
            goto out_quota;
    }

    error = ea_dealloc_block(ip);

out_quota:
    gfs2_quota_unhold(ip);
    return error;
}

static const struct xattr_handler gfs2_xattr_user_handler = {
    .prefix = XATTR_USER_PREFIX,
    .flags  = GFS2_EATYPE_USR,
    .get    = gfs2_xattr_get,
    .set    = gfs2_xattr_set,
};

static const struct xattr_handler gfs2_xattr_security_handler = {
    .prefix = XATTR_SECURITY_PREFIX,
    .flags  = GFS2_EATYPE_SECURITY,
    .get    = gfs2_xattr_get,
    .set    = gfs2_xattr_set,
};

const struct xattr_handler *gfs2_xattr_handlers[] = {
    &gfs2_xattr_user_handler,
    &gfs2_xattr_security_handler,
    &gfs2_xattr_system_handler,
    NULL,
};