diff options
Diffstat (limited to 'fs/gfs2/dir.c')
| -rw-r--r-- | fs/gfs2/dir.c | 1974 |
1 files changed, 1974 insertions, 0 deletions
diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c new file mode 100644 index 00000000000..6918a58261e --- /dev/null +++ b/fs/gfs2/dir.c @@ -0,0 +1,1974 @@ +/* + * 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 v.2. + */ + +/* + * Implements Extendible Hashing as described in: + * "Extendible Hashing" by Fagin, et al in + * __ACM Trans. on Database Systems__, Sept 1979. + * + * + * Here's the layout of dirents which is essentially the same as that of ext2 + * within a single block. The field de_name_len is the number of bytes + * actually required for the name (no null terminator). The field de_rec_len + * is the number of bytes allocated to the dirent. The offset of the next + * dirent in the block is (dirent + dirent->de_rec_len). When a dirent is + * deleted, the preceding dirent inherits its allocated space, ie + * prev->de_rec_len += deleted->de_rec_len. Since the next dirent is obtained + * by adding de_rec_len to the current dirent, this essentially causes the + * deleted dirent to get jumped over when iterating through all the dirents. + * + * When deleting the first dirent in a block, there is no previous dirent so + * the field de_ino is set to zero to designate it as deleted. When allocating + * a dirent, gfs2_dirent_alloc iterates through the dirents in a block. If the + * first dirent has (de_ino == 0) and de_rec_len is large enough, this first + * dirent is allocated. Otherwise it must go through all the 'used' dirents + * searching for one in which the amount of total space minus the amount of + * used space will provide enough space for the new dirent. + * + * There are two types of blocks in which dirents reside. In a stuffed dinode, + * the dirents begin at offset sizeof(struct gfs2_dinode) from the beginning of + * the block. In leaves, they begin at offset sizeof(struct gfs2_leaf) from the + * beginning of the leaf block. The dirents reside in leaves when + * + * dip->i_di.di_flags & GFS2_DIF_EXHASH is true + * + * Otherwise, the dirents are "linear", within a single stuffed dinode block. + * + * When the dirents are in leaves, the actual contents of the directory file are + * used as an array of 64-bit block pointers pointing to the leaf blocks. The + * dirents are NOT in the directory file itself. There can be more than one + * block pointer in the array that points to the same leaf. In fact, when a + * directory is first converted from linear to exhash, all of the pointers + * point to the same leaf. + * + * When a leaf is completely full, the size of the hash table can be + * doubled unless it is already at the maximum size which is hard coded into + * GFS2_DIR_MAX_DEPTH. After that, leaves are chained together in a linked list, + * but never before the maximum hash table size has been reached. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/buffer_head.h> +#include <linux/sort.h> +#include <linux/gfs2_ondisk.h> +#include <linux/crc32.h> +#include <linux/vmalloc.h> + +#include "gfs2.h" +#include "lm_interface.h" +#include "incore.h" +#include "dir.h" +#include "glock.h" +#include "inode.h" +#include "meta_io.h" +#include "quota.h" +#include "rgrp.h" +#include "trans.h" +#include "bmap.h" +#include "util.h" + +#define IS_LEAF 1 /* Hashed (leaf) directory */ +#define IS_DINODE 2 /* Linear (stuffed dinode block) directory */ + +#if 1 +#define gfs2_disk_hash2offset(h) (((uint64_t)(h)) >> 1) +#define gfs2_dir_offset2hash(p) ((uint32_t)(((uint64_t)(p)) << 1)) +#else +#define gfs2_disk_hash2offset(h) (((uint64_t)(h))) +#define gfs2_dir_offset2hash(p) ((uint32_t)(((uint64_t)(p)))) +#endif + +typedef int (*leaf_call_t) (struct gfs2_inode *dip, + uint32_t index, uint32_t len, uint64_t leaf_no, + void *data); + + +int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, uint64_t block, + struct buffer_head **bhp) +{ + struct buffer_head *bh; + + bh = gfs2_meta_new(ip->i_gl, block); + gfs2_trans_add_bh(ip->i_gl, bh, 1); + gfs2_metatype_set(bh, GFS2_METATYPE_JD, GFS2_FORMAT_JD); + gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header)); + *bhp = bh; + return 0; +} + +static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, uint64_t block, + struct buffer_head **bhp) +{ + struct buffer_head *bh; + int error; + + error = gfs2_meta_read(ip->i_gl, block, DIO_START | DIO_WAIT, &bh); + if (error) + return error; + if (gfs2_metatype_check(ip->i_sbd, bh, GFS2_METATYPE_JD)) { + brelse(bh); + return -EIO; + } + *bhp = bh; + return 0; +} + +static int gfs2_dir_write_stuffed(struct gfs2_inode *ip, const char *buf, + unsigned int offset, unsigned int size) + +{ + struct buffer_head *dibh; + int error; + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + return error; + + gfs2_trans_add_bh(ip->i_gl, dibh, 1); + memcpy(dibh->b_data + offset + sizeof(struct gfs2_dinode), buf, size); + if (ip->i_di.di_size < offset + size) + ip->i_di.di_size = offset + size; + ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds(); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + + brelse(dibh); + + return size; +} + + + +/** + * gfs2_dir_write_data - Write directory information to the inode + * @ip: The GFS2 inode + * @buf: The buffer containing information to be written + * @offset: The file offset to start writing at + * @size: The amount of data to write + * + * Returns: The number of bytes correctly written or error code + */ +static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf, + uint64_t offset, unsigned int size) +{ + struct gfs2_sbd *sdp = ip->i_sbd; + struct buffer_head *dibh; + uint64_t lblock, dblock; + uint32_t extlen = 0; + unsigned int o; + int copied = 0; + int error = 0; + + if (!size) + return 0; + + if (gfs2_is_stuffed(ip) && + offset + size <= sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) + return gfs2_dir_write_stuffed(ip, buf, (unsigned int)offset, + size); + + if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip))) + return -EINVAL; + + if (gfs2_is_stuffed(ip)) { + error = gfs2_unstuff_dinode(ip, NULL, NULL); + if (error) + return error; + } + + lblock = offset; + o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header); + + while (copied < size) { + unsigned int amount; + struct buffer_head *bh; + int new; + + amount = size - copied; + if (amount > sdp->sd_sb.sb_bsize - o) + amount = sdp->sd_sb.sb_bsize - o; + + if (!extlen) { + new = 1; + error = gfs2_extent_map(ip->i_vnode, lblock, &new, + &dblock, &extlen); + if (error) + goto fail; + error = -EIO; + if (gfs2_assert_withdraw(sdp, dblock)) + goto fail; + } + + if (amount == sdp->sd_jbsize || new) + error = gfs2_dir_get_new_buffer(ip, dblock, &bh); + else + error = gfs2_dir_get_existing_buffer(ip, dblock, &bh); + + if (error) + goto fail; + + gfs2_trans_add_bh(ip->i_gl, bh, 1); + memcpy(bh->b_data + o, buf, amount); + brelse(bh); + if (error) + goto fail; + + copied += amount; + lblock++; + dblock++; + extlen--; + + o = sizeof(struct gfs2_meta_header); + } + +out: + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + return error; + + if (ip->i_di.di_size < offset + copied) + ip->i_di.di_size = offset + copied; + ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds(); + + gfs2_trans_add_bh(ip->i_gl, dibh, 1); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + brelse(dibh); + + return copied; +fail: + if (copied) + goto out; + return error; +} + +static int gfs2_dir_read_stuffed(struct gfs2_inode *ip, char *buf, + unsigned int offset, unsigned int size) +{ + struct buffer_head *dibh; + int error; + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (!error) { + offset += sizeof(struct gfs2_dinode); + memcpy(buf, dibh->b_data + offset, size); + brelse(dibh); + } + + return (error) ? error : size; +} + + +/** + * gfs2_dir_read_data - Read a data from a directory inode + * @ip: The GFS2 Inode + * @buf: The buffer to place result into + * @offset: File offset to begin jdata_readng from + * @size: Amount of data to transfer + * + * Returns: The amount of data actually copied or the error + */ +static int gfs2_dir_read_data(struct gfs2_inode *ip, char *buf, + uint64_t offset, unsigned int size) +{ + struct gfs2_sbd *sdp = ip->i_sbd; + uint64_t lblock, dblock; + uint32_t extlen = 0; + unsigned int o; + int copied = 0; + int error = 0; + + if (offset >= ip->i_di.di_size) + return 0; + + if ((offset + size) > ip->i_di.di_size) + size = ip->i_di.di_size - offset; + + if (!size) + return 0; + + if (gfs2_is_stuffed(ip)) + return gfs2_dir_read_stuffed(ip, buf, (unsigned int)offset, + size); + + if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip))) + return -EINVAL; + + lblock = offset; + o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header); + + while (copied < size) { + unsigned int amount; + struct buffer_head *bh; + int new; + + amount = size - copied; + if (amount > sdp->sd_sb.sb_bsize - o) + amount = sdp->sd_sb.sb_bsize - o; + + if (!extlen) { + new = 0; + error = gfs2_extent_map(ip->i_vnode, lblock, &new, + &dblock, &extlen); + if (error) + goto fail; + } + + if (extlen > 1) + gfs2_meta_ra(ip->i_gl, dblock, extlen); + + if (dblock) { + if (new) + error = gfs2_dir_get_new_buffer(ip, dblock, &bh); + else + error = gfs2_dir_get_existing_buffer(ip, dblock, &bh); + if (error) + goto fail; + dblock++; + extlen--; + } else + bh = NULL; + + memcpy(buf, bh->b_data + o, amount); + brelse(bh); + if (error) + goto fail; + + copied += amount; + lblock++; + + o = sizeof(struct gfs2_meta_header); + } + + return copied; +fail: + return (copied) ? copied : error; +} + +typedef int (*gfs2_dscan_t)(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque); + +static inline int __gfs2_dirent_find(const struct gfs2_dirent *dent, + const struct qstr *name, int ret) +{ + if (dent->de_inum.no_addr != 0 && + be32_to_cpu(dent->de_hash) == name->hash && + be16_to_cpu(dent->de_name_len) == name->len && + memcmp((char *)(dent+1), name->name, name->len) == 0) + return ret; + return 0; +} + +static int gfs2_dirent_find(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque) +{ + return __gfs2_dirent_find(dent, name, 1); +} + +static int gfs2_dirent_prev(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque) +{ + return __gfs2_dirent_find(dent, name, 2); +} + +/* + * name->name holds ptr to start of block. + * name->len holds size of block. + */ +static int gfs2_dirent_last(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque) +{ + const char *start = name->name; + const char *end = (const char *)dent + be16_to_cpu(dent->de_rec_len); + if (name->len == (end - start)) + return 1; + return 0; +} + +static int gfs2_dirent_find_space(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque) +{ + unsigned required = GFS2_DIRENT_SIZE(name->len); + unsigned actual = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len)); + unsigned totlen = be16_to_cpu(dent->de_rec_len); + + if (!dent->de_inum.no_addr) + actual = GFS2_DIRENT_SIZE(0); + if ((totlen - actual) >= required) + return 1; + return 0; +} + +struct dirent_gather { + const struct gfs2_dirent **pdent; + unsigned offset; +}; + +static int gfs2_dirent_gather(const struct gfs2_dirent *dent, + const struct qstr *name, + void *opaque) +{ + struct dirent_gather *g = opaque; + if (dent->de_inum.no_addr) { + g->pdent[g->offset++] = dent; + } + return 0; +} + +/* + * Other possible things to check: + * - Inode located within filesystem size (and on valid block) + * - Valid directory entry type + * Not sure how heavy-weight we want to make this... could also check + * hash is correct for example, but that would take a lot of extra time. + * For now the most important thing is to check that the various sizes + * are correct. + */ +static int gfs2_check_dirent(struct gfs2_dirent *dent, unsigned int offset, + unsigned int size, unsigned int len, int first) +{ + const char *msg = "gfs2_dirent too small"; + if (unlikely(size < sizeof(struct gfs2_dirent))) + goto error; + msg = "gfs2_dirent misaligned"; + if (unlikely(offset & 0x7)) + goto error; + msg = "gfs2_dirent points beyond end of block"; + if (unlikely(offset + size > len)) + goto error; + msg = "zero inode number"; + if (unlikely(!first && !dent->de_inum.no_addr)) + goto error; + msg = "name length is greater than space in dirent"; + if (dent->de_inum.no_addr && + unlikely(sizeof(struct gfs2_dirent)+be16_to_cpu(dent->de_name_len) > + size)) + goto error; + return 0; +error: + printk(KERN_WARNING "gfs2_check_dirent: %s (%s)\n", msg, + first ? "first in block" : "not first in block"); + return -EIO; +} + +static int gfs2_dirent_offset(const void *buf) +{ + const struct gfs2_meta_header *h = buf; + int offset; + + BUG_ON(buf == NULL); + + switch(be32_to_cpu(h->mh_type)) { + case GFS2_METATYPE_LF: + offset = sizeof(struct gfs2_leaf); + break; + case GFS2_METATYPE_DI: + offset = sizeof(struct gfs2_dinode); + break; + default: + goto wrong_type; + } + return offset; +wrong_type: + printk(KERN_WARNING "gfs2_scan_dirent: wrong block type %u\n", + be32_to_cpu(h->mh_type)); + return -1; +} + +static struct gfs2_dirent *gfs2_dirent_scan(struct inode *inode, + void *buf, + unsigned int len, gfs2_dscan_t scan, + const struct qstr *name, + void *opaque) +{ + struct gfs2_dirent *dent, *prev; + unsigned offset; + unsigned size; + int ret = 0; + + ret = gfs2_dirent_offset(buf); + if (ret < 0) + goto consist_inode; + + offset = ret; + prev = NULL; + dent = (struct gfs2_dirent *)(buf + offset); + size = be16_to_cpu(dent->de_rec_len); + if (gfs2_check_dirent(dent, offset, size, len, 1)) + goto consist_inode; + do { + ret = scan(dent, name, opaque); + if (ret) + break; + offset += size; + if (offset == len) + break; + prev = dent; + dent = (struct gfs2_dirent *)(buf + offset); + size = be16_to_cpu(dent->de_rec_len); + if (gfs2_check_dirent(dent, offset, size, len, 0)) + goto consist_inode; + } while(1); + + switch(ret) { + case 0: + return NULL; + case 1: + return dent; + case 2: + return prev ? prev : dent; + default: + BUG_ON(ret > 0); + return ERR_PTR(ret); + } + +consist_inode: + gfs2_consist_inode(inode->u.generic_ip); + return ERR_PTR(-EIO); +} + + +/** + * dirent_first - Return the first dirent + * @dip: the directory + * @bh: The buffer + * @dent: Pointer to list of dirents + * + * return first dirent whether bh points to leaf or stuffed dinode + * + * Returns: IS_LEAF, IS_DINODE, or -errno + */ + +static int dirent_first(struct gfs2_inode *dip, struct buffer_head *bh, + struct gfs2_dirent **dent) +{ + struct gfs2_meta_header *h = (struct gfs2_meta_header *)bh->b_data; + + if (be32_to_cpu(h->mh_type) == GFS2_METATYPE_LF) { + if (gfs2_meta_check(dip->i_sbd, bh)) + return -EIO; + *dent = (struct gfs2_dirent *)(bh->b_data + + sizeof(struct gfs2_leaf)); + return IS_LEAF; + } else { + if (gfs2_metatype_check(dip->i_sbd, bh, GFS2_METATYPE_DI)) + return -EIO; + *dent = (struct gfs2_dirent *)(bh->b_data + + sizeof(struct gfs2_dinode)); + return IS_DINODE; + } +} + +/** + * dirent_next - Next dirent + * @dip: the directory + * @bh: The buffer + * @dent: Pointer to list of dirents + * + * Returns: 0 on success, error code otherwise + */ + +static int dirent_next(struct gfs2_inode *dip, struct buffer_head *bh, + struct gfs2_dirent **dent) +{ + struct gfs2_dirent *tmp, *cur; + char *bh_end; + uint16_t cur_rec_len; + + cur = *dent; + bh_end = bh->b_data + bh->b_size; + cur_rec_len = be16_to_cpu(cur->de_rec_len); + + if ((char *)cur + cur_rec_len >= bh_end) { + if ((char *)cur + cur_rec_len > bh_end) { + gfs2_consist_inode(dip); + return -EIO; + } + return -ENOENT; + } + + tmp = (struct gfs2_dirent *)((char *)cur + cur_rec_len); + + if ((char *)tmp + be16_to_cpu(tmp->de_rec_len) > bh_end) { + gfs2_consist_inode(dip); + return -EIO; + } + + if (cur_rec_len == 0) { + gfs2_consist_inode(dip); + return -EIO; + } + + /* Only the first dent could ever have de_inum.no_addr == 0 */ + if (!tmp->de_inum.no_addr) { + gfs2_consist_inode(dip); + return -EIO; + } + + *dent = tmp; + + return 0; +} + +/** + * dirent_del - Delete a dirent + * @dip: The GFS2 inode + * @bh: The buffer + * @prev: The previous dirent + * @cur: The current dirent + * + */ + +static void dirent_del(struct gfs2_inode *dip, struct buffer_head *bh, + struct gfs2_dirent *prev, struct gfs2_dirent *cur) +{ + uint16_t cur_rec_len, prev_rec_len; + + if (!cur->de_inum.no_addr) { + gfs2_consist_inode(dip); + return; + } + + gfs2_trans_add_bh(dip->i_gl, bh, 1); + + /* If there is no prev entry, this is the first entry in the block. + The de_rec_len is already as big as it needs to be. Just zero + out the inode number and return. */ + + if (!prev) { + cur->de_inum.no_addr = 0; /* No endianess worries */ + return; + } + + /* Combine this dentry with the previous one. */ + + prev_rec_len = be16_to_cpu(prev->de_rec_len); + cur_rec_len = be16_to_cpu(cur->de_rec_len); + + if ((char *)prev + prev_rec_len != (char *)cur) + gfs2_consist_inode(dip); + if ((char *)cur + cur_rec_len > bh->b_data + bh->b_size) + gfs2_consist_inode(dip); + + prev_rec_len += cur_rec_len; + prev->de_rec_len = cpu_to_be16(prev_rec_len); +} + +/* + * Takes a dent from which to grab space as an argument. Returns the + * newly created dent. + */ +static struct gfs2_dirent *gfs2_init_dirent(struct inode *inode, + struct gfs2_dirent *dent, + const struct qstr *name, + struct buffer_head *bh) +{ + struct gfs2_inode *ip = inode->u.generic_ip; + struct gfs2_dirent *ndent; + unsigned offset = 0, totlen; + + if (dent->de_inum.no_addr) + offset = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len)); + totlen = be16_to_cpu(dent->de_rec_len); + BUG_ON(offset + name->len > totlen); + gfs2_trans_add_bh(ip->i_gl, bh, 1); + ndent = (struct gfs2_dirent *)((char *)dent + offset); + dent->de_rec_len = cpu_to_be16(offset); + gfs2_qstr2dirent(name, totlen - offset, ndent); + return ndent; +} + +static struct gfs2_dirent *gfs2_dirent_alloc(struct inode *inode, + struct buffer_head *bh, + const struct qstr *name) +{ + struct gfs2_dirent *dent; + dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, + gfs2_dirent_find_space, name, NULL); + if (!dent || IS_ERR(dent)) + return dent; + return gfs2_init_dirent(inode, dent, name, bh); +} + +static int get_leaf(struct gfs2_inode *dip, uint64_t leaf_no, + struct buffer_head **bhp) +{ + int error; + + error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_START | DIO_WAIT, bhp); + if (!error && gfs2_metatype_check(dip->i_sbd, *bhp, GFS2_METATYPE_LF)) + error = -EIO; + + return error; +} + +/** + * get_leaf_nr - Get a leaf number associated with the index + * @dip: The GFS2 inode + * @index: + * @leaf_out: + * + * Returns: 0 on success, error code otherwise + */ + +static int get_leaf_nr(struct gfs2_inode *dip, uint32_t index, + uint64_t *leaf_out) +{ + uint64_t leaf_no; + int error; + + error = gfs2_dir_read_data(dip, (char *)&leaf_no, + index * sizeof(uint64_t), + sizeof(uint64_t)); + if (error != sizeof(uint64_t)) + return (error < 0) ? error : -EIO; + + *leaf_out = be64_to_cpu(leaf_no); + + return 0; +} + +static int get_first_leaf(struct gfs2_inode *dip, uint32_t index, + struct buffer_head **bh_out) +{ + uint64_t leaf_no; + int error; + + error = get_leaf_nr(dip, index, &leaf_no); + if (!error) + error = get_leaf(dip, leaf_no, bh_out); + + return error; +} + +static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode, + const struct qstr *name, + gfs2_dscan_t scan, + struct buffer_head **pbh) +{ + struct buffer_head *bh; + struct gfs2_dirent *dent; + struct gfs2_inode *ip = inode->u.generic_ip; + int error; + + if (ip->i_di.di_flags & GFS2_DIF_EXHASH) { + struct gfs2_leaf *leaf; + unsigned hsize = 1 << ip->i_di.di_depth; + unsigned index; + u64 ln; + if (hsize * sizeof(u64) != ip->i_di.di_size) { + gfs2_consist_inode(ip); + return ERR_PTR(-EIO); + } + + index = name->hash >> (32 - ip->i_di.di_depth); + error = get_first_leaf(ip, index, &bh); + if (error) + return ERR_PTR(error); + do { + dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, + scan, name, NULL); + if (dent) + goto got_dent; + leaf = (struct gfs2_leaf *)bh->b_data; + ln = be64_to_cpu(leaf->lf_next); + brelse(bh); + if (!ln) + break; + error = get_leaf(ip, ln, &bh); + } while(!error); + + return error ? ERR_PTR(error) : NULL; + } + + error = gfs2_meta_inode_buffer(ip, &bh); + if (error) + return ERR_PTR(error); + dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, scan, name, NULL); +got_dent: + if (unlikely(dent == NULL || IS_ERR(dent))) { + brelse(bh); + bh = NULL; + } + *pbh = bh; + return dent; +} + +static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, u16 depth) +{ + struct gfs2_inode *ip = inode->u.generic_ip; + u64 bn = gfs2_alloc_meta(ip); + struct buffer_head *bh = gfs2_meta_new(ip->i_gl, bn); + struct gfs2_leaf *leaf; + struct gfs2_dirent *dent; + struct qstr name = { .name = "", .len = 0, .hash = 0 }; + if (!bh) + return NULL; + gfs2_trans_add_bh(ip->i_gl, bh, 1); + gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF); + leaf = (struct gfs2_leaf *)bh->b_data; + leaf->lf_depth = cpu_to_be16(depth); + leaf->lf_entries = cpu_to_be16(0); + leaf->lf_dirent_format = cpu_to_be16(GFS2_FORMAT_DE); + leaf->lf_next = cpu_to_be64(0); + memset(leaf->lf_reserved, 0, sizeof(leaf->lf_reserved)); + dent = (struct gfs2_dirent *)(leaf+1); + gfs2_qstr2dirent(&name, bh->b_size - sizeof(struct gfs2_leaf), dent); + *pbh = bh; + return leaf; +} + +/** + * dir_make_exhash - Convert a stuffed directory into an ExHash directory + * @dip: The GFS2 inode + * + * Returns: 0 on success, error code otherwise + */ + +static int dir_make_exhash(struct inode *inode) +{ + struct gfs2_inode *dip = inode->u.generic_ip; + struct gfs2_sbd *sdp = dip->i_sbd; + struct gfs2_dirent *dent; + struct qstr args; + struct buffer_head *bh, *dibh; + struct gfs2_leaf *leaf; + int y; + uint32_t x; + uint64_t *lp, bn; + int error; + + error = gfs2_meta_inode_buffer(dip, &dibh); + if (error) + return error; + + /* Turn over a new leaf */ + + leaf = new_leaf(inode, &bh, 0); + if (!leaf) + return -ENOSPC; + bn = bh->b_blocknr; + + gfs2_assert(sdp, dip->i_di.di_entries < (1 << 16)); + leaf->lf_entries = cpu_to_be16(dip->i_di.di_entries); + + /* Copy dirents */ + + gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_leaf), dibh, + sizeof(struct gfs2_dinode)); + + /* Find last entry */ + + x = 0; + args.len = bh->b_size - sizeof(struct gfs2_dinode) + + sizeof(struct gfs2_leaf); + args.name = bh->b_data; + dent = gfs2_dirent_scan(dip->i_vnode, bh->b_data, bh->b_size, + gfs2_dirent_last, &args, NULL); + if (!dent) { + brelse(bh); + brelse(dibh); + return -EIO; + } + if (IS_ERR(dent)) { + brelse(bh); + brelse(dibh); + return PTR_ERR(dent); + } + + /* Adjust the last dirent's record length + (Remember that dent still points to the last entry.) */ + + dent->de_rec_len = cpu_to_be16(be16_to_cpu(dent->de_rec_len) + + sizeof(struct gfs2_dinode) - + sizeof(struct gfs2_leaf)); + + brelse(bh); + + /* We're done with the new leaf block, now setup the new + hash table. */ + + gfs2_trans_add_bh(dip->i_gl, dibh, 1); + gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); + + lp = (uint64_t *)(dibh->b_data + sizeof(struct gfs2_dinode)); + + for (x = sdp->sd_hash_ptrs; x--; lp++) + *lp = cpu_to_be64(bn); + + dip->i_di.di_size = sdp->sd_sb.sb_bsize / 2; + dip->i_di.di_blocks++; + dip->i_di.di_flags |= GFS2_DIF_EXHASH; + dip->i_di.di_payload_format = 0; + + for (x = sdp->sd_hash_ptrs, y = -1; x; x >>= 1, y++) ; + dip->i_di.di_depth = y; + + gfs2_dinode_out(&dip->i_di, dibh->b_data); + + brelse(dibh); + + return 0; +} + +/** + * dir_split_leaf - Split a leaf block into two + * @dip: The GFS2 inode + * @index: + * @leaf_no: + * + * Returns: 0 on success, error code on failure + */ + +static int dir_split_leaf(struct inode *inode, const struct qstr *name) +{ + struct gfs2_inode *dip = inode->u.generic_ip; + struct buffer_head *nbh, *obh, *dibh; + struct gfs2_leaf *nleaf, *oleaf; + struct gfs2_dirent *dent, *prev = NULL, *next = NULL, *new; + uint32_t start, len, half_len, divider; + uint64_t bn, *lp, leaf_no; + uint32_t index; + int x, moved = 0; + int error; + + index = name->hash >> (32 - dip->i_di.di_depth); + error = get_leaf_nr(dip, index, &leaf_no); + if (error) + return error; + + /* Get the old leaf block */ + error = get_leaf(dip, leaf_no, &obh); + if (error) + return error; + + oleaf = (struct gfs2_leaf *)obh->b_data; + if (dip->i_di.di_depth == be16_to_cpu(oleaf->lf_depth)) { + brelse(obh); + return 1; /* can't split */ + } + + gfs2_trans_add_bh(dip->i_gl, obh, 1); + + nleaf = new_leaf(inode, &nbh, be16_to_cpu(oleaf->lf_depth) + 1); + if (!nleaf) { + brelse(obh); + return -ENOSPC; + } + bn = nbh->b_blocknr; + + /* Compute the start and len of leaf pointers in the hash table. */ + len = 1 << (dip->i_di.di_depth - be16_to_cpu(oleaf->lf_depth)); + half_len = len >> 1; + if (!half_len) { + printk(KERN_WARNING "di_depth %u lf_depth %u index %u\n", dip->i_di.di_depth, be16_to_cpu(oleaf->lf_depth), index); + gfs2_consist_inode(dip); + error = -EIO; + goto fail_brelse; + } + + start = (index & ~(len - 1)); + + /* Change the pointers. + Don't bother distinguishing stuffed from non-stuffed. + This code is complicated enough already. */ + lp = kmalloc(half_len * sizeof(uint64_t), GFP_NOFS | __GFP_NOFAIL); + /* Change the pointers */ + for (x = 0; x < half_len; x++) + lp[x] = cpu_to_be64(bn); + + error = gfs2_dir_write_data(dip, (char *)lp, start * sizeof(uint64_t), + half_len * sizeof(uint64_t)); + if (error != half_len * sizeof(uint64_t)) { + if (error >= 0) + error = -EIO; + goto fail_lpfree; + } + + kfree(lp); + + /* Compute the divider */ + divider = (start + half_len) << (32 - dip->i_di.di_depth); + + /* Copy the entries */ + dirent_first(dip, obh, &dent); + + do { + next = dent; + if (dirent_next(dip, obh, &next)) + next = NULL; + + if (dent->de_inum.no_addr && + be32_to_cpu(dent->de_hash) < divider) { + struct qstr str; + str.name = (char*)(dent+1); + str.len = be16_to_cpu(dent->de_name_len); + str.hash = be32_to_cpu(dent->de_hash); + new = gfs2_dirent_alloc(inode, nbh, &str); + if (IS_ERR(new)) { + error = PTR_ERR(new); + break; + } + + new->de_inum = dent->de_inum; /* No endian worries */ + new->de_type = dent->de_type; /* No endian worries */ + nleaf->lf_entries = cpu_to_be16(be16_to_cpu(nleaf->lf_entries)+1); + + dirent_del(dip, obh, prev, dent); + + if (!oleaf->lf_entries) + gfs2_consist_inode(dip); + oleaf->lf_entries = cpu_to_be16(be16_to_cpu(oleaf->lf_entries)-1); + + if (!prev) + prev = dent; + + moved = 1; + } else { + prev = dent; + } + dent = next; + } while (dent); + + oleaf->lf_depth = nleaf->lf_depth; + + error = gfs2_meta_inode_buffer(dip, &dibh); + if (!gfs2_assert_withdraw(dip->i_sbd, !error)) { + dip->i_di.di_blocks++; + gfs2_dinode_out(&dip->i_di, dibh->b_data); + brelse(dibh); + } + + brelse(obh); + brelse(nbh); + + return error; + +fail_lpfree: + kfree(lp); + +fail_brelse: + brelse(obh); + brelse(nbh); + return error; +} + +/** + * dir_double_exhash - Double size of ExHash table + * @dip: The GFS2 dinode + * + * Returns: 0 on success, error code on failure + */ + +static int dir_double_exhash(struct gfs2_inode *dip) +{ + struct gfs2_sbd *sdp = dip->i_sbd; + struct buffer_head *dibh; + uint32_t hsize; + uint64_t *buf; + uint64_t *from, *to; + uint64_t block; + int x; + int error = 0; + + hsize = 1 << dip->i_di.di_depth; + if (hsize * sizeof(uint64_t) != dip->i_di.di_size) { + gfs2_consist_inode(dip); + return -EIO; + } + + /* Allocate both the "from" and "to" buffers in one big chunk */ + + buf = kcalloc(3, sdp->sd_hash_bsize, GFP_KERNEL | __GFP_NOFAIL); + + for (block = dip->i_di.di_size >> sdp->sd_hash_bsize_shift; block--;) { + error = gfs2_dir_read_data(dip, (char *)buf, + block * sdp->sd_hash_bsize, + sdp->sd_hash_bsize); + if (error != sdp->sd_hash_bsize) { + if (error >= 0) + error = -EIO; + goto fail; + } + + from = buf; + to = (uint64_t *)((char *)buf + sdp->sd_hash_bsize); + + for (x = sdp->sd_hash_ptrs; x--; from++) { + *to++ = *from; /* No endianess worries */ + *to++ = *from; + } + + error = gfs2_dir_write_data(dip, + (char *)buf + sdp->sd_hash_bsize, + block * sdp->sd_sb.sb_bsize, + sdp->sd_sb.sb_bsize); + if (error != sdp->sd_sb.sb_bsize) { + if (error >= 0) + error = -EIO; + goto fail; + } + } + + kfree(buf); + + error = gfs2_meta_inode_buffer(dip, &dibh); + if (!gfs2_assert_withdraw(sdp, !error)) { + dip->i_di.di_depth++; + gfs2_dinode_out(&dip->i_di, dibh->b_data); + brelse(dibh); + } + + return error; + + fail: + kfree(buf); + + return error; +} + +/** + * compare_dents - compare directory entries by hash value + * @a: first dent + * @b: second dent + * + * When comparing the hash entries of @a to @b: + * gt: returns 1 + * lt: returns -1 + * eq: returns 0 + */ + +static int compare_dents(const void *a, const void *b) +{ + struct gfs2_dirent *dent_a, *dent_b; + uint32_t hash_a, hash_b; + int ret = 0; + + dent_a = *(struct gfs2_dirent **)a; + hash_a = be32_to_cpu(dent_a->de_hash); + + dent_b = *(struct gfs2_dirent **)b; + hash_b = be32_to_cpu(dent_b->de_hash); + + if (hash_a > hash_b) + ret = 1; + else if (hash_a < hash_b) + ret = -1; + else { + unsigned int len_a = be16_to_cpu(dent_a->de_name_len); + unsigned int len_b = be16_to_cpu(dent_b->de_name_len); + + if (len_a > len_b) + ret = 1; + else if (len_a < len_b) + ret = -1; + else + ret = memcmp((char *)(dent_a + 1), + (char *)(dent_b + 1), + len_a); + } + + return ret; +} + +/** + * do_filldir_main - read out directory entries + * @dip: The GFS2 inode + * @offset: The offset in the file to read from + * @opaque: opaque data to pass to filldir + * @filldir: The function to pass entries to + * @darr: an array of struct gfs2_dirent pointers to read + * @entries: the number of entries in darr + * @copied: pointer to int that's non-zero if a entry has been copied out + * + * Jump through some hoops to make sure that if there are hash collsions, + * they are read out at the beginning of a buffer. We want to minimize + * the possibility that they will fall into different readdir buffers or + * that someone will want to seek to that location. + * + * Returns: errno, >0 on exception from filldir + */ + +static int do_filldir_main(struct gfs2_inode *dip, uint64_t *offset, + void *opaque, gfs2_filldir_t filldir, + const struct gfs2_dirent **darr, uint32_t entries, + int *copied) +{ + const struct gfs2_dirent *dent, *dent_next; + struct gfs2_inum inum; + uint64_t off, off_next; + unsigned int x, y; + int run = 0; + int error = 0; + + sort(darr, entries, sizeof(struct gfs2_dirent *), compare_dents, NULL); + + dent_next = darr[0]; + off_next = be32_to_cpu(dent_next->de_hash); + off_next = gfs2_disk_hash2offset(off_next); + + for (x = 0, y = 1; x < entries; x++, y++) { + dent = dent_next; + off = off_next; + + if (y < entries) { + dent_next = darr[y]; + off_next = be32_to_cpu(dent_next->de_hash); + off_next = gfs2_disk_hash2offset(off_next); + + if (off < *offset) + continue; + *offset = off; + + if (off_next == off) { + if (*copied && !run) + return 1; + run = 1; + } else + run = 0; + } else { + if (off < *offset) + continue; + *offset = off; + } + + gfs2_inum_in(&inum, (char *)&dent->de_inum); + + error = filldir(opaque, (char *)(dent + 1), + be16_to_cpu(dent->de_name_len), + off, &inum, + be16_to_cpu(dent->de_type)); + if (error) + return 1; + + *copied = 1; + } + + /* Increment the *offset by one, so the next time we come into the + do_filldir fxn, we get the next entry instead of the last one in the + current leaf */ + + (*offset)++; + + return 0; +} + +static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque, + gfs2_filldir_t filldir, int *copied, + unsigned *depth, u64 leaf_no) +{ + struct gfs2_inode *ip = inode->u.generic_ip; + struct buffer_head *bh; + struct gfs2_leaf *lf; + unsigned entries = 0; + unsigned leaves = 0; + const struct gfs2_dirent **darr, *dent; + struct dirent_gather g; + struct buffer_head **larr; + int leaf = 0; + int error, i; + u64 lfn = leaf_no; + + do { + error = get_leaf(ip, lfn, &bh); + if (error) + goto out; + lf = (struct gfs2_leaf *)bh->b_data; + if (leaves == 0) + *depth = be16_to_cpu(lf->lf_depth); + entries += be16_to_cpu(lf->lf_entries); + leaves++; + lfn = be64_to_cpu(lf->lf_next); + brelse(bh); + } while(lfn); + + if (!entries) + return 0; + + error = -ENOMEM; + larr = vmalloc((leaves + entries) * sizeof(void*)); + if (!larr) + goto out; + darr = (const struct gfs2_dirent **)(larr + leaves); + g.pdent = darr; + g.offset = 0; + lfn = leaf_no; + + do { + error = get_leaf(ip, lfn, &bh); + if (error) + goto out_kfree; + lf = (struct gfs2_leaf *)bh->b_data; + lfn = be64_to_cpu(lf->lf_next); + if (lf->lf_entries) { + dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, + gfs2_dirent_gather, NULL, &g); + error = PTR_ERR(dent); + if (IS_ERR(dent)) { + goto out_kfree; + } + error = 0; + larr[leaf++] = bh; + } else { + brelse(bh); + } + } while(lfn); + + error = do_filldir_main(ip, offset, opaque, filldir, darr, + entries, copied); +out_kfree: + for(i = 0; i < leaf; i++) + brelse(larr[i]); + vfree(larr); +out: + return error; +} + +/** + * dir_e_read - Reads the entries from a directory into a filldir buffer + * @dip: dinode pointer + * @offset: the hash of the last entry read shifted to the right once + * @opaque: buffer for the filldir function to fill + * @filldir: points to the filldir function to use + * + * Returns: errno + */ + +static int dir_e_read(struct inode *inode, uint64_t *offset, void *opaque, + gfs2_filldir_t filldir) +{ + struct gfs2_inode *dip = inode->u.generic_ip; + struct gfs2_sbd *sdp = dip->i_sbd; + uint32_t hsize, len = 0; + uint32_t ht_offset, lp_offset, ht_offset_cur = -1; + uint32_t hash, index; + uint64_t *lp; + int copied = 0; + int error = 0; + unsigned depth; + + hsize = 1 << dip->i_di.di_depth; + if (hsize * sizeof(uint64_t) != dip->i_di.di_size) { + gfs2_consist_inode(dip); + return -EIO; + } + + hash = gfs2_dir_offset2hash(*offset); + index = hash >> (32 - dip->i_di.di_depth); + + lp = kmalloc(sdp->sd_hash_bsize, GFP_KERNEL); + if (!lp) + return -ENOMEM; + + while (index < hsize) { + lp_offset = index & (sdp->sd_hash_ptrs - 1); + ht_offset = index - lp_offset; + + if (ht_offset_cur != ht_offset) { + error = gfs2_dir_read_data(dip, (char *)lp, + ht_offset * sizeof(uint64_t), + sdp->sd_hash_bsize); + if (error != sdp->sd_hash_bsize) { + if (error >= 0) + error = -EIO; + goto out; + } + ht_offset_cur = ht_offset; + } + + error = gfs2_dir_read_leaf(inode, offset, opaque, filldir, + &copied, &depth, + be64_to_cpu(lp[lp_offset])); + if (error) + break; + + len = 1 << (dip->i_di.di_depth - depth); + index = (index & ~(len - 1)) + len; + } + +out: + kfree(lp); + if (error > 0) + error = 0; + return error; +} + +int gfs2_dir_read(struct inode *inode, uint64_t *offset, void *opaque, + gfs2_filldir_t filldir) +{ + struct gfs2_inode *dip = inode->u.generic_ip; + struct dirent_gather g; + const struct gfs2_dirent **darr, *dent; + struct buffer_head *dibh; + int copied = 0; + int error; + + if (!dip->i_di.di_entries) + return 0; + + if (dip->i_di.di_flags & GFS2_DIF_EXHASH) + return dir_e_read(inode, offset, opaque, filldir); + + if (!gfs2_is_stuffed(dip)) { + gfs2_consist_inode(dip); + return -EIO; + } + + error = gfs2_meta_inode_buffer(dip, &dibh); + if (error) + return error; + + error = -ENOMEM; + darr = kmalloc(dip->i_di.di_entries * sizeof(struct gfs2_dirent *), + GFP_KERNEL); + if (darr) { + g.pdent = darr; + g.offset = 0; + dent = gfs2_dirent_scan(inode, dibh->b_data, dibh->b_size, + gfs2_dirent_gather, NULL, &g); + if (IS_ERR(dent)) { + error = PTR_ERR(dent); + goto out; + } + error = do_filldir_main(dip, offset, opaque, filldir, darr, + dip->i_di.di_entries, &copied); +out: + kfree(darr); + } + + if (error > 0) + error = 0; + + brelse(dibh); + + return error; +} + +/** + * gfs2_dir_search - Search a directory + * @dip: The GFS2 inode + * @filename: + * @inode: + * + * This routine searches a directory for a file or another directory. + * Assumes a glock is held on dip. + * + * Returns: errno + */ + +int gfs2_dir_search(struct inode *dir, const struct qstr *name, + struct gfs2_inum *inum, unsigned int *type) +{ + struct buffer_head *bh; + struct gfs2_dirent *dent; + + dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh); + if (dent) { + if (IS_ERR(dent)) + return PTR_ERR(dent); + if (inum) + gfs2_inum_in(inum, (char *)&dent->de_inum); + if (type) + *type = be16_to_cpu(dent->de_type); + brelse(bh); + return 0; + } + return -ENOENT; +} + +static int dir_new_leaf(struct inode *inode, const struct qstr *name) +{ + struct buffer_head *bh, *obh; + struct gfs2_inode *ip = inode->u.generic_ip; + struct gfs2_leaf *leaf, *oleaf; + int error; + u32 index; + u64 bn; + + index = name->hash >> (32 - ip->i_di.di_depth); + error = get_first_leaf(ip, index, &obh); + if (error) + return error; + do { + oleaf = (struct gfs2_leaf *)obh->b_data; + bn = be64_to_cpu(oleaf->lf_next); + if (!bn) + break; + brelse(obh); + error = get_leaf(ip, bn, &obh); + if (error) + return error; + } while(1); + + gfs2_trans_add_bh(ip->i_gl, obh, 1); + + leaf = new_leaf(inode, &bh, be16_to_cpu(oleaf->lf_depth)); + if (!leaf) { + brelse(obh); + return -ENOSPC; + } + oleaf->lf_next = cpu_to_be64(bh->b_blocknr); + brelse(bh); + brelse(obh); + + error = gfs2_meta_inode_buffer(ip, &bh); + if (error) + return error; + gfs2_trans_add_bh(ip->i_gl, bh, 1); + ip->i_di.di_blocks++; + gfs2_dinode_out(&ip->i_di, bh->b_data); + brelse(bh); + return 0; +} + +/** + * gfs2_dir_add - Add new filename into directory + * @dip: The GFS2 inode + * @filename: The new name + * @inode: The inode number of the entry + * @type: The type of the entry + * + * Returns: 0 on success, error code on failure + */ + +int gfs2_dir_add(struct inode *inode, const struct qstr *name, + const struct gfs2_inum *inum, unsigned type) +{ + struct gfs2_inode *ip = inode->u.generic_ip; + struct buffer_head *bh; + struct gfs2_dirent *dent; + struct gfs2_leaf *leaf; + int error; + + while(1) { + dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, + &bh); + if (dent) { + if (IS_ERR(dent)) + return PTR_ERR(dent); + dent = gfs2_init_dirent(inode, dent, name, bh); + gfs2_inum_out(inum, (char *)&dent->de_inum); + dent->de_type = cpu_to_be16(type); + if (ip->i_di.di_flags & GFS2_DIF_EXHASH) { + leaf = (struct gfs2_leaf *)bh->b_data; + leaf->lf_entries = cpu_to_be16(be16_to_cpu(leaf->lf_entries) + 1); + } + brelse(bh); + error = gfs2_meta_inode_buffer(ip, &bh); + if (error) + break; + gfs2_trans_add_bh(ip->i_gl, bh, 1); + ip->i_di.di_entries++; + ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds(); + gfs2_dinode_out(&ip->i_di, bh->b_data); + brelse(bh); + error = 0; + break; + } + if (!(ip->i_di.di_flags & GFS2_DIF_EXHASH)) { + error = dir_make_exhash(inode); + if (error) + break; + continue; + } + error = dir_split_leaf(inode, name); + if (error == 0) + continue; + if (error < 0) + break; + if (ip->i_di.di_depth < GFS2_DIR_MAX_DEPTH) { + error = dir_double_exhash(ip); + if (error) + break; + error = dir_split_leaf(inode, name); + if (error < 0) + break; + if (error == 0) + continue; + } + error = dir_new_leaf(inode, name); + if (!error) + continue; + error = -ENOSPC; + break; + } + return error; +} + + +/** + * gfs2_dir_del - Delete a directory entry + * @dip: The GFS2 inode + * @filename: The filename + * + * Returns: 0 on success, error code on failure + */ + +int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *name) +{ + struct gfs2_dirent *dent, *prev = NULL; + struct buffer_head *bh; + int error; + + /* Returns _either_ the entry (if its first in block) or the + previous entry otherwise */ + dent = gfs2_dirent_search(dip->i_vnode, name, gfs2_dirent_prev, &bh); + if (!dent) { + gfs2_consist_inode(dip); + return -EIO; + } + if (IS_ERR(dent)) { + gfs2_consist_inode(dip); + return PTR_ERR(dent); + } + /* If not first in block, adjust pointers accordingly */ + if (gfs2_dirent_find(dent, name, NULL) == 0) { + prev = dent; + dent = (struct gfs2_dirent *)((char *)dent + be16_to_cpu(prev->de_rec_len)); + } + + dirent_del(dip, bh, prev, dent); + if (dip->i_di.di_flags & GFS2_DIF_EXHASH) { + struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data; + u16 entries = be16_to_cpu(leaf->lf_entries); + if (!entries) + gfs2_consist_inode(dip); + leaf->lf_entries = cpu_to_be16(--entries); + } + brelse(bh); + + error = gfs2_meta_inode_buffer(dip, &bh); + if (error) + return error; + + if (!dip->i_di.di_entries) + gfs2_consist_inode(dip); + gfs2_trans_add_bh(dip->i_gl, bh, 1); + dip->i_di.di_entries--; + dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds(); + gfs2_dinode_out(&dip->i_di, bh->b_data); + brelse(bh); + + return error; +} + +/** + * gfs2_dir_mvino - Change inode number of directory entry + * @dip: The GFS2 inode + * @filename: + * @new_inode: + * + * This routine changes the inode number of a directory entry. It's used + * by rename to change ".." when a directory is moved. + * Assumes a glock is held on dvp. + * + * Returns: errno + */ + +int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename, + struct gfs2_inum *inum, unsigned int new_type) +{ + struct buffer_head *bh; + struct gfs2_dirent *dent; + int error; + + dent = gfs2_dirent_search(dip->i_vnode, filename, gfs2_dirent_find, &bh); + if (!dent) { + gfs2_consist_inode(dip); + return -EIO; + } + if (IS_ERR(dent)) + return PTR_ERR(dent); + + gfs2_trans_add_bh(dip->i_gl, bh, 1); + gfs2_inum_out(inum, (char *)&dent->de_inum); + dent->de_type = cpu_to_be16(new_type); + + if (dip->i_di.di_flags & GFS2_DIF_EXHASH) { + brelse(bh); + error = gfs2_meta_inode_buffer(dip, &bh); + if (error) + return error; + gfs2_trans_add_bh(dip->i_gl, bh, 1); + } + + dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds(); + gfs2_dinode_out(&dip->i_di, bh->b_data); + brelse(bh); + return 0; +} + +/** + * foreach_leaf - call a function for each leaf in a directory + * @dip: the directory + * @lc: the function to call for each each + * @data: private data to pass to it + * + * Returns: errno + */ + +static int foreach_leaf(struct gfs2_inode *dip, leaf_call_t lc, void *data) +{ + struct gfs2_sbd *sdp = dip->i_sbd; + struct buffer_head *bh; + struct gfs2_leaf *leaf; + uint32_t hsize, len; + uint32_t ht_offset, lp_offset, ht_offset_cur = -1; + uint32_t index = 0; + uint64_t *lp; + uint64_t leaf_no; + int error = 0; + + hsize = 1 << dip->i_di.di_depth; + if (hsize * sizeof(uint64_t) != dip->i_di.di_size) { + gfs2_consist_inode(dip); + return -EIO; + } + + lp = kmalloc(sdp->sd_hash_bsize, GFP_KERNEL); + if (!lp) + return -ENOMEM; + + while (index < hsize) { + lp_offset = index & (sdp->sd_hash_ptrs - 1); + ht_offset = index - lp_offset; + + if (ht_offset_cur != ht_offset) { + error = gfs2_dir_read_data(dip, (char *)lp, + ht_offset * sizeof(uint64_t), + sdp->sd_hash_bsize); + if (error != sdp->sd_hash_bsize) { + if (error >= 0) + error = -EIO; + goto out; + } + ht_offset_cur = ht_offset; + } + + leaf_no = be64_to_cpu(lp[lp_offset]); + if (leaf_no) { + error = get_leaf(dip, leaf_no, &bh); + if (error) + goto out; + leaf = (struct gfs2_leaf *)bh->b_data; + brelse(bh); + + len = 1 << (dip->i_di.di_depth - be16_to_cpu(leaf->lf_depth)); + + error = lc(dip, index, len, leaf_no, data); + if (error) + goto out; + + index = (index & ~(len - 1)) + len; + } else + index++; + } + + if (index != hsize) { + gfs2_consist_inode(dip); + error = -EIO; + } + + out: + kfree(lp); + + return error; +} + +/** + * leaf_dealloc - Deallocate a directory leaf + * @dip: the directory + * @index: the hash table offset in the directory + * @len: the number of pointers to this leaf + * @leaf_no: the leaf number + * @data: not used + * + * Returns: errno + */ + +static int leaf_dealloc(struct gfs2_inode *dip, uint32_t index, uint32_t len, + uint64_t leaf_no, void *data) +{ + struct gfs2_sbd *sdp = dip->i_sbd; + struct gfs2_leaf *tmp_leaf; + struct gfs2_rgrp_list rlist; + struct buffer_head *bh, *dibh; + uint64_t blk, nblk; + unsigned int rg_blocks = 0, l_blocks = 0; + char *ht; + unsigned int x, size = len * sizeof(uint64_t); + int error; + + memset(&rlist, 0, sizeof(struct gfs2_rgrp_list)); + + ht = kzalloc(size, GFP_KERNEL); + if (!ht) + return -ENOMEM; + + gfs2_alloc_get(dip); + + error = gfs2_quota_hold(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); + if (error) + goto out; + + error = gfs2_rindex_hold(sdp, &dip->i_alloc.al_ri_gh); + if (error) + goto out_qs; + + /* Count the number of leaves */ + + for (blk = leaf_no; blk; blk = nblk) { + error = get_leaf(dip, blk, &bh); + if (error) + goto out_rlist; + tmp_leaf = (struct gfs2_leaf *)bh->b_data; + nblk = be64_to_cpu(tmp_leaf->lf_next); + brelse(bh); + + gfs2_rlist_add(sdp, &rlist, blk); + l_blocks++; + } + + gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE, 0); + + 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_ri.ri_length; + } + + error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs); + if (error) + goto out_rlist; + + error = gfs2_trans_begin(sdp, + rg_blocks + (DIV_ROUND_UP(size, sdp->sd_jbsize) + 1) + + RES_DINODE + RES_STATFS + RES_QUOTA, l_blocks); + if (error) + goto out_rg_gunlock; + + for (blk = leaf_no; blk; blk = nblk) { + error = get_leaf(dip, blk, &bh); + if (error) + goto out_end_trans; + tmp_leaf = (struct gfs2_leaf *)bh->b_data; + nblk = be64_to_cpu(tmp_leaf->lf_next); + brelse(bh); + + gfs2_free_meta(dip, blk, 1); + + if (!dip->i_di.di_blocks) + gfs2_consist_inode(dip); + dip->i_di.di_blocks--; + } + + error = gfs2_dir_write_data(dip, ht, index * sizeof(uint64_t), size); + if (error != size) { + if (error >= 0) + error = -EIO; + goto out_end_trans; + } + + error = gfs2_meta_inode_buffer(dip, &dibh); + if (error) + goto out_end_trans; + + gfs2_trans_add_bh(dip->i_gl, dibh, 1); + gfs2_dinode_out(&dip->i_di, dibh->b_data); + brelse(dibh); + + out_end_trans: + gfs2_trans_end(sdp); + + out_rg_gunlock: + gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs); + + out_rlist: + gfs2_rlist_free(&rlist); + gfs2_glock_dq_uninit(&dip->i_alloc.al_ri_gh); + + out_qs: + gfs2_quota_unhold(dip); + + out: + gfs2_alloc_put(dip); + kfree(ht); + + return error; +} + +/** + * gfs2_dir_exhash_dealloc - free all the leaf blocks in a directory + * @dip: the directory + * + * Dealloc all on-disk directory leaves to FREEMETA state + * Change on-disk inode type to "regular file" + * + * Returns: errno + */ + +int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip) +{ + struct gfs2_sbd *sdp = dip->i_sbd; + struct buffer_head *bh; + int error; + + /* Dealloc on-disk leaves to FREEMETA state */ + error = foreach_leaf(dip, leaf_dealloc, NULL); + if (error) + return error; + + /* Make this a regular file in case we crash. + (We don't want to free these blocks a second time.) */ + + error = gfs2_trans_begin(sdp, RES_DINODE, 0); + if (error) + return error; + + error = gfs2_meta_inode_buffer(dip, &bh); + if (!error) { + gfs2_trans_add_bh(dip->i_gl, bh, 1); + ((struct gfs2_dinode *)bh->b_data)->di_mode = + cpu_to_be32(S_IFREG); + brelse(bh); + } + + gfs2_trans_end(sdp); + + return error; +} + +/** + * gfs2_diradd_alloc_required - find if adding entry will require an allocation + * @ip: the file being written to + * @filname: the filename that's going to be added + * + * Returns: 1 if alloc required, 0 if not, -ve on error + */ + +int gfs2_diradd_alloc_required(struct inode *inode, const struct qstr *name) +{ + struct gfs2_dirent *dent; + struct buffer_head *bh; + + dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, &bh); + if (!dent) { + return 1; + } + if (IS_ERR(dent)) + return PTR_ERR(dent); + brelse(bh); + return 0; +} + |