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rgrp.c
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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2008 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/fs.h>
#include <linux/gfs2_ondisk.h>
#include <linux/prefetch.h>
#include <linux/blkdev.h>
#include "gfs2.h"
#include "incore.h"
#include "glock.h"
#include "glops.h"
#include "lops.h"
#include "meta_io.h"
#include "quota.h"
#include "rgrp.h"
#include "super.h"
#include "trans.h"
#include "util.h"
#include "log.h"
#include "inode.h"
#include "trace_gfs2.h"
#define BFITNOENT ((u32)~0)
#define NO_BLOCK ((u64)~0)
#if BITS_PER_LONG == 32
#define LBITMASK (0x55555555UL)
#define LBITSKIP55 (0x55555555UL)
#define LBITSKIP00 (0x00000000UL)
#else
#define LBITMASK (0x5555555555555555UL)
#define LBITSKIP55 (0x5555555555555555UL)
#define LBITSKIP00 (0x0000000000000000UL)
#endif
/*
* These routines are used by the resource group routines (rgrp.c)
* to keep track of block allocation. Each block is represented by two
* bits. So, each byte represents GFS2_NBBY (i.e. 4) blocks.
*
* 0 = Free
* 1 = Used (not metadata)
* 2 = Unlinked (still in use) inode
* 3 = Used (metadata)
*/
static const char valid_change[16] = {
/* current */
/* n */ 0, 1, 1, 1,
/* e */ 1, 0, 0, 0,
/* w */ 0, 0, 0, 1,
1, 0, 0, 0
};
static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32 goal,
unsigned char old_state, unsigned char new_state,
unsigned int *n);
/**
* gfs2_setbit - Set a bit in the bitmaps
* @buffer: the buffer that holds the bitmaps
* @buflen: the length (in bytes) of the buffer
* @block: the block to set
* @new_state: the new state of the block
*
*/
static inline void gfs2_setbit(struct gfs2_rgrpd *rgd, unsigned char *buf1,
unsigned char *buf2, unsigned int offset,
unsigned int buflen, u32 block,
unsigned char new_state)
{
unsigned char *byte1, *byte2, *end, cur_state;
const unsigned int bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
byte1 = buf1 + offset + (block / GFS2_NBBY);
end = buf1 + offset + buflen;
BUG_ON(byte1 >= end);
cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
if (unlikely(!valid_change[new_state * 4 + cur_state])) {
gfs2_consist_rgrpd(rgd);
return;
}
*byte1 ^= (cur_state ^ new_state) << bit;
if (buf2) {
byte2 = buf2 + offset + (block / GFS2_NBBY);
cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
*byte2 ^= (cur_state ^ new_state) << bit;
}
}
/**
* gfs2_testbit - test a bit in the bitmaps
* @buffer: the buffer that holds the bitmaps
* @buflen: the length (in bytes) of the buffer
* @block: the block to read
*
*/
static inline unsigned char gfs2_testbit(struct gfs2_rgrpd *rgd,
const unsigned char *buffer,
unsigned int buflen, u32 block)
{
const unsigned char *byte, *end;
unsigned char cur_state;
unsigned int bit;
byte = buffer + (block / GFS2_NBBY);
bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
end = buffer + buflen;
gfs2_assert(rgd->rd_sbd, byte < end);
cur_state = (*byte >> bit) & GFS2_BIT_MASK;
return cur_state;
}
/**
* gfs2_bit_search
* @ptr: Pointer to bitmap data
* @mask: Mask to use (normally 0x55555.... but adjusted for search start)
* @state: The state we are searching for
*
* We xor the bitmap data with a patter which is the bitwise opposite
* of what we are looking for, this gives rise to a pattern of ones
* wherever there is a match. Since we have two bits per entry, we
* take this pattern, shift it down by one place and then and it with
* the original. All the even bit positions (0,2,4, etc) then represent
* successful matches, so we mask with 0x55555..... to remove the unwanted
* odd bit positions.
*
* This allows searching of a whole u64 at once (32 blocks) with a
* single test (on 64 bit arches).
*/
static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state)
{
u64 tmp;
static const u64 search[] = {
[0] = 0xffffffffffffffffULL,
[1] = 0xaaaaaaaaaaaaaaaaULL,
[2] = 0x5555555555555555ULL,
[3] = 0x0000000000000000ULL,
};
tmp = le64_to_cpu(*ptr) ^ search[state];
tmp &= (tmp >> 1);
tmp &= mask;
return tmp;
}
/**
* gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
* a block in a given allocation state.
* @buffer: the buffer that holds the bitmaps
* @len: the length (in bytes) of the buffer
* @goal: start search at this block's bit-pair (within @buffer)
* @state: GFS2_BLKST_XXX the state of the block we're looking for.
*
* Scope of @goal and returned block number is only within this bitmap buffer,
* not entire rgrp or filesystem. @buffer will be offset from the actual
* beginning of a bitmap block buffer, skipping any header structures, but
* headers are always a multiple of 64 bits long so that the buffer is
* always aligned to a 64 bit boundary.
*
* The size of the buffer is in bytes, but is it assumed that it is
* always ok to read a complete multiple of 64 bits at the end
* of the block in case the end is no aligned to a natural boundary.
*
* Return: the block number (bitmap buffer scope) that was found
*/
static u32 gfs2_bitfit(const u8 *buf, const unsigned int len,
u32 goal, u8 state)
{
u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1);
const __le64 *ptr = ((__le64 *)buf) + (goal >> 5);
const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64)));
u64 tmp;
u64 mask = 0x5555555555555555ULL;
u32 bit;
BUG_ON(state > 3);
/* Mask off bits we don't care about at the start of the search */
mask <<= spoint;
tmp = gfs2_bit_search(ptr, mask, state);
ptr++;
while(tmp == 0 && ptr < end) {
tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state);
ptr++;
}
/* Mask off any bits which are more than len bytes from the start */
if (ptr == end && (len & (sizeof(u64) - 1)))
tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1))));
/* Didn't find anything, so return */
if (tmp == 0)
return BFITNOENT;
ptr--;
bit = __ffs64(tmp);
bit /= 2; /* two bits per entry in the bitmap */
return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit;
}
/**
* gfs2_bitcount - count the number of bits in a certain state
* @buffer: the buffer that holds the bitmaps
* @buflen: the length (in bytes) of the buffer
* @state: the state of the block we're looking for
*
* Returns: The number of bits
*/
static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer,
unsigned int buflen, u8 state)
{
const u8 *byte = buffer;
const u8 *end = buffer + buflen;
const u8 state1 = state << 2;
const u8 state2 = state << 4;
const u8 state3 = state << 6;
u32 count = 0;
for (; byte < end; byte++) {
if (((*byte) & 0x03) == state)
count++;
if (((*byte) & 0x0C) == state1)
count++;
if (((*byte) & 0x30) == state2)
count++;
if (((*byte) & 0xC0) == state3)
count++;
}
return count;
}
/**
* gfs2_rgrp_verify - Verify that a resource group is consistent
* @sdp: the filesystem
* @rgd: the rgrp
*
*/
void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
struct gfs2_bitmap *bi = NULL;
u32 length = rgd->rd_length;
u32 count[4], tmp;
int buf, x;
memset(count, 0, 4 * sizeof(u32));
/* Count # blocks in each of 4 possible allocation states */
for (buf = 0; buf < length; buf++) {
bi = rgd->rd_bits + buf;
for (x = 0; x < 4; x++)
count[x] += gfs2_bitcount(rgd,
bi->bi_bh->b_data +
bi->bi_offset,
bi->bi_len, x);
}
if (count[0] != rgd->rd_free) {
if (gfs2_consist_rgrpd(rgd))
fs_err(sdp, "free data mismatch: %u != %u\n",
count[0], rgd->rd_free);
return;
}
tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes;
if (count[1] != tmp) {
if (gfs2_consist_rgrpd(rgd))
fs_err(sdp, "used data mismatch: %u != %u\n",
count[1], tmp);
return;
}
if (count[2] + count[3] != rgd->rd_dinodes) {
if (gfs2_consist_rgrpd(rgd))
fs_err(sdp, "used metadata mismatch: %u != %u\n",
count[2] + count[3], rgd->rd_dinodes);
return;
}
}
static inline int rgrp_contains_block(struct gfs2_rgrpd *rgd, u64 block)
{
u64 first = rgd->rd_data0;
u64 last = first + rgd->rd_data;
return first <= block && block < last;
}
/**
* gfs2_blk2rgrpd - Find resource group for a given data/meta block number
* @sdp: The GFS2 superblock
* @n: The data block number
*
* Returns: The resource group, or NULL if not found
*/
struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk)
{
struct gfs2_rgrpd *rgd;
spin_lock(&sdp->sd_rindex_spin);
list_for_each_entry(rgd, &sdp->sd_rindex_mru_list, rd_list_mru) {
if (rgrp_contains_block(rgd, blk)) {
list_move(&rgd->rd_list_mru, &sdp->sd_rindex_mru_list);
spin_unlock(&sdp->sd_rindex_spin);
return rgd;
}
}
spin_unlock(&sdp->sd_rindex_spin);
return NULL;
}
/**
* gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
* @sdp: The GFS2 superblock
*
* Returns: The first rgrp in the filesystem
*/
struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
{
gfs2_assert(sdp, !list_empty(&sdp->sd_rindex_list));
return list_entry(sdp->sd_rindex_list.next, struct gfs2_rgrpd, rd_list);
}
/**
* gfs2_rgrpd_get_next - get the next RG
* @rgd: A RG
*
* Returns: The next rgrp
*/
struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
{
if (rgd->rd_list.next == &rgd->rd_sbd->sd_rindex_list)
return NULL;
return list_entry(rgd->rd_list.next, struct gfs2_rgrpd, rd_list);
}
static void clear_rgrpdi(struct gfs2_sbd *sdp)
{
struct list_head *head;
struct gfs2_rgrpd *rgd;
struct gfs2_glock *gl;
spin_lock(&sdp->sd_rindex_spin);
sdp->sd_rindex_forward = NULL;
spin_unlock(&sdp->sd_rindex_spin);
head = &sdp->sd_rindex_list;
while (!list_empty(head)) {
rgd = list_entry(head->next, struct gfs2_rgrpd, rd_list);
gl = rgd->rd_gl;
list_del(&rgd->rd_list);
list_del(&rgd->rd_list_mru);
if (gl) {
gl->gl_object = NULL;
gfs2_glock_put(gl);
}
kfree(rgd->rd_bits);
kmem_cache_free(gfs2_rgrpd_cachep, rgd);
}
}
void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
{
mutex_lock(&sdp->sd_rindex_mutex);
clear_rgrpdi(sdp);
mutex_unlock(&sdp->sd_rindex_mutex);
}
static void gfs2_rindex_print(const struct gfs2_rgrpd *rgd)
{
printk(KERN_INFO " ri_addr = %llu\n", (unsigned long long)rgd->rd_addr);
printk(KERN_INFO " ri_length = %u\n", rgd->rd_length);
printk(KERN_INFO " ri_data0 = %llu\n", (unsigned long long)rgd->rd_data0);
printk(KERN_INFO " ri_data = %u\n", rgd->rd_data);
printk(KERN_INFO " ri_bitbytes = %u\n", rgd->rd_bitbytes);
}
/**
* gfs2_compute_bitstructs - Compute the bitmap sizes
* @rgd: The resource group descriptor
*
* Calculates bitmap descriptors, one for each block that contains bitmap data
*
* Returns: errno
*/
static int compute_bitstructs(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
struct gfs2_bitmap *bi;
u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */
u32 bytes_left, bytes;
int x;
if (!length)
return -EINVAL;
rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS);
if (!rgd->rd_bits)
return -ENOMEM;
bytes_left = rgd->rd_bitbytes;
for (x = 0; x < length; x++) {
bi = rgd->rd_bits + x;
bi->bi_flags = 0;
/* small rgrp; bitmap stored completely in header block */
if (length == 1) {
bytes = bytes_left;
bi->bi_offset = sizeof(struct gfs2_rgrp);
bi->bi_start = 0;
bi->bi_len = bytes;
/* header block */
} else if (x == 0) {
bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
bi->bi_offset = sizeof(struct gfs2_rgrp);
bi->bi_start = 0;
bi->bi_len = bytes;
/* last block */
} else if (x + 1 == length) {
bytes = bytes_left;
bi->bi_offset = sizeof(struct gfs2_meta_header);
bi->bi_start = rgd->rd_bitbytes - bytes_left;
bi->bi_len = bytes;
/* other blocks */
} else {
bytes = sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header);
bi->bi_offset = sizeof(struct gfs2_meta_header);
bi->bi_start = rgd->rd_bitbytes - bytes_left;
bi->bi_len = bytes;
}
bytes_left -= bytes;
}
if (bytes_left) {
gfs2_consist_rgrpd(rgd);
return -EIO;
}
bi = rgd->rd_bits + (length - 1);
if ((bi->bi_start + bi->bi_len) * GFS2_NBBY != rgd->rd_data) {
if (gfs2_consist_rgrpd(rgd)) {
gfs2_rindex_print(rgd);
fs_err(sdp, "start=%u len=%u offset=%u\n",
bi->bi_start, bi->bi_len, bi->bi_offset);
}
return -EIO;
}
return 0;
}
/**
* gfs2_ri_total - Total up the file system space, according to the rindex.
*
*/
u64 gfs2_ri_total(struct gfs2_sbd *sdp)
{
u64 total_data = 0;
struct inode *inode = sdp->sd_rindex;
struct gfs2_inode *ip = GFS2_I(inode);
char buf[sizeof(struct gfs2_rindex)];
struct file_ra_state ra_state;
int error, rgrps;
mutex_lock(&sdp->sd_rindex_mutex);
file_ra_state_init(&ra_state, inode->i_mapping);
for (rgrps = 0;; rgrps++) {
loff_t pos = rgrps * sizeof(struct gfs2_rindex);
if (pos + sizeof(struct gfs2_rindex) >= ip->i_disksize)
break;
error = gfs2_internal_read(ip, &ra_state, buf, &pos,
sizeof(struct gfs2_rindex));
if (error != sizeof(struct gfs2_rindex))
break;
total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data);
}
mutex_unlock(&sdp->sd_rindex_mutex);
return total_data;
}
static void gfs2_rindex_in(struct gfs2_rgrpd *rgd, const void *buf)
{
const struct gfs2_rindex *str = buf;
rgd->rd_addr = be64_to_cpu(str->ri_addr);
rgd->rd_length = be32_to_cpu(str->ri_length);
rgd->rd_data0 = be64_to_cpu(str->ri_data0);
rgd->rd_data = be32_to_cpu(str->ri_data);
rgd->rd_bitbytes = be32_to_cpu(str->ri_bitbytes);
}
/**
* read_rindex_entry - Pull in a new resource index entry from the disk
* @gl: The glock covering the rindex inode
*
* Returns: 0 on success, error code otherwise
*/
static int read_rindex_entry(struct gfs2_inode *ip,
struct file_ra_state *ra_state)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
char buf[sizeof(struct gfs2_rindex)];
int error;
struct gfs2_rgrpd *rgd;
error = gfs2_internal_read(ip, ra_state, buf, &pos,
sizeof(struct gfs2_rindex));
if (!error)
return 0;
if (error != sizeof(struct gfs2_rindex)) {
if (error > 0)
error = -EIO;
return error;
}
rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS);
error = -ENOMEM;
if (!rgd)
return error;
mutex_init(&rgd->rd_mutex);
lops_init_le(&rgd->rd_le, &gfs2_rg_lops);
rgd->rd_sbd = sdp;
list_add_tail(&rgd->rd_list, &sdp->sd_rindex_list);
list_add_tail(&rgd->rd_list_mru, &sdp->sd_rindex_mru_list);
gfs2_rindex_in(rgd, buf);
error = compute_bitstructs(rgd);
if (error)
return error;
error = gfs2_glock_get(sdp, rgd->rd_addr,
&gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
if (error)
return error;
rgd->rd_gl->gl_object = rgd;
rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
return error;
}
/**
* gfs2_ri_update - Pull in a new resource index from the disk
* @ip: pointer to the rindex inode
*
* Returns: 0 on successful update, error code otherwise
*/
static int gfs2_ri_update(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct inode *inode = &ip->i_inode;
struct file_ra_state ra_state;
u64 rgrp_count = ip->i_disksize;
int error;
if (do_div(rgrp_count, sizeof(struct gfs2_rindex))) {
gfs2_consist_inode(ip);
return -EIO;
}
clear_rgrpdi(sdp);
file_ra_state_init(&ra_state, inode->i_mapping);
for (sdp->sd_rgrps = 0; sdp->sd_rgrps < rgrp_count; sdp->sd_rgrps++) {
error = read_rindex_entry(ip, &ra_state);
if (error) {
clear_rgrpdi(sdp);
return error;
}
}
sdp->sd_rindex_uptodate = 1;
return 0;
}
/**
* gfs2_ri_update_special - Pull in a new resource index from the disk
*
* This is a special version that's safe to call from gfs2_inplace_reserve_i.
* In this case we know that we don't have any resource groups in memory yet.
*
* @ip: pointer to the rindex inode
*
* Returns: 0 on successful update, error code otherwise
*/
static int gfs2_ri_update_special(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct inode *inode = &ip->i_inode;
struct file_ra_state ra_state;
int error;
file_ra_state_init(&ra_state, inode->i_mapping);
for (sdp->sd_rgrps = 0;; sdp->sd_rgrps++) {
/* Ignore partials */
if ((sdp->sd_rgrps + 1) * sizeof(struct gfs2_rindex) >
ip->i_disksize)
break;
error = read_rindex_entry(ip, &ra_state);
if (error) {
clear_rgrpdi(sdp);
return error;
}
}
sdp->sd_rindex_uptodate = 1;
return 0;
}
/**
* gfs2_rindex_hold - Grab a lock on the rindex
* @sdp: The GFS2 superblock
* @ri_gh: the glock holder
*
* We grab a lock on the rindex inode to make sure that it doesn't
* change whilst we are performing an operation. We keep this lock
* for quite long periods of time compared to other locks. This
* doesn't matter, since it is shared and it is very, very rarely
* accessed in the exclusive mode (i.e. only when expanding the filesystem).
*
* This makes sure that we're using the latest copy of the resource index
* special file, which might have been updated if someone expanded the
* filesystem (via gfs2_grow utility), which adds new resource groups.
*
* Returns: 0 on success, error code otherwise
*/
int gfs2_rindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ri_gh)
{
struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
struct gfs2_glock *gl = ip->i_gl;
int error;
error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, ri_gh);
if (error)
return error;
/* Read new copy from disk if we don't have the latest */
if (!sdp->sd_rindex_uptodate) {
mutex_lock(&sdp->sd_rindex_mutex);
if (!sdp->sd_rindex_uptodate) {
error = gfs2_ri_update(ip);
if (error)
gfs2_glock_dq_uninit(ri_gh);
}
mutex_unlock(&sdp->sd_rindex_mutex);
}
return error;
}
static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf)
{
const struct gfs2_rgrp *str = buf;
u32 rg_flags;
rg_flags = be32_to_cpu(str->rg_flags);
rg_flags &= ~GFS2_RDF_MASK;
rgd->rd_flags &= GFS2_RDF_MASK;
rgd->rd_flags |= rg_flags;
rgd->rd_free = be32_to_cpu(str->rg_free);
rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes);
rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration);
}
static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf)
{
struct gfs2_rgrp *str = buf;
str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK);
str->rg_free = cpu_to_be32(rgd->rd_free);
str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes);
str->__pad = cpu_to_be32(0);
str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration);
memset(&str->rg_reserved, 0, sizeof(str->rg_reserved));
}
/**
* gfs2_rgrp_bh_get - Read in a RG's header and bitmaps
* @rgd: the struct gfs2_rgrpd describing the RG to read in
*
* Read in all of a Resource Group's header and bitmap blocks.
* Caller must eventually call gfs2_rgrp_relse() to free the bitmaps.
*
* Returns: errno
*/
int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
struct gfs2_glock *gl = rgd->rd_gl;
unsigned int length = rgd->rd_length;
struct gfs2_bitmap *bi;
unsigned int x, y;
int error;
mutex_lock(&rgd->rd_mutex);
spin_lock(&sdp->sd_rindex_spin);
if (rgd->rd_bh_count) {
rgd->rd_bh_count++;
spin_unlock(&sdp->sd_rindex_spin);
mutex_unlock(&rgd->rd_mutex);
return 0;
}
spin_unlock(&sdp->sd_rindex_spin);
for (x = 0; x < length; x++) {
bi = rgd->rd_bits + x;
error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, &bi->bi_bh);
if (error)
goto fail;
}
for (y = length; y--;) {
bi = rgd->rd_bits + y;
error = gfs2_meta_wait(sdp, bi->bi_bh);
if (error)
goto fail;
if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB :
GFS2_METATYPE_RG)) {
error = -EIO;
goto fail;
}
}
if (!(rgd->rd_flags & GFS2_RDF_UPTODATE)) {
for (x = 0; x < length; x++)
clear_bit(GBF_FULL, &rgd->rd_bits[x].bi_flags);
gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
rgd->rd_flags |= (GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
}
spin_lock(&sdp->sd_rindex_spin);
rgd->rd_free_clone = rgd->rd_free;
rgd->rd_bh_count++;
spin_unlock(&sdp->sd_rindex_spin);
mutex_unlock(&rgd->rd_mutex);
return 0;
fail:
while (x--) {
bi = rgd->rd_bits + x;
brelse(bi->bi_bh);
bi->bi_bh = NULL;
gfs2_assert_warn(sdp, !bi->bi_clone);
}
mutex_unlock(&rgd->rd_mutex);
return error;
}
void gfs2_rgrp_bh_hold(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
spin_lock(&sdp->sd_rindex_spin);
gfs2_assert_warn(rgd->rd_sbd, rgd->rd_bh_count);
rgd->rd_bh_count++;
spin_unlock(&sdp->sd_rindex_spin);
}
/**
* gfs2_rgrp_bh_put - Release RG bitmaps read in with gfs2_rgrp_bh_get()
* @rgd: the struct gfs2_rgrpd describing the RG to read in
*
*/
void gfs2_rgrp_bh_put(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
int x, length = rgd->rd_length;
spin_lock(&sdp->sd_rindex_spin);
gfs2_assert_warn(rgd->rd_sbd, rgd->rd_bh_count);
if (--rgd->rd_bh_count) {
spin_unlock(&sdp->sd_rindex_spin);
return;
}
for (x = 0; x < length; x++) {
struct gfs2_bitmap *bi = rgd->rd_bits + x;
kfree(bi->bi_clone);
bi->bi_clone = NULL;
brelse(bi->bi_bh);
bi->bi_bh = NULL;
}
spin_unlock(&sdp->sd_rindex_spin);
}
static void gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
const struct gfs2_bitmap *bi)
{
struct super_block *sb = sdp->sd_vfs;
struct block_device *bdev = sb->s_bdev;
const unsigned int sects_per_blk = sdp->sd_sb.sb_bsize /
bdev_logical_block_size(sb->s_bdev);
u64 blk;
sector_t start = 0;
sector_t nr_sects = 0;
int rv;
unsigned int x;
for (x = 0; x < bi->bi_len; x++) {
const u8 *orig = bi->bi_bh->b_data + bi->bi_offset + x;
const u8 *clone = bi->bi_clone + bi->bi_offset + x;
u8 diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1));
diff &= 0x55;
if (diff == 0)
continue;
blk = offset + ((bi->bi_start + x) * GFS2_NBBY);
blk *= sects_per_blk; /* convert to sectors */
while(diff) {
if (diff & 1) {
if (nr_sects == 0)
goto start_new_extent;
if ((start + nr_sects) != blk) {
rv = blkdev_issue_discard(bdev, start,
nr_sects, GFP_NOFS,
DISCARD_FL_BARRIER);
if (rv)
goto fail;
nr_sects = 0;
start_new_extent:
start = blk;
}
nr_sects += sects_per_blk;
}
diff >>= 2;
blk += sects_per_blk;
}
}
if (nr_sects) {
rv = blkdev_issue_discard(bdev, start, nr_sects, GFP_NOFS,
DISCARD_FL_BARRIER);
if (rv)
goto fail;
}
return;
fail:
fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem", rv);
sdp->sd_args.ar_discard = 0;
}
void gfs2_rgrp_repolish_clones(struct gfs2_rgrpd *rgd)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
unsigned int length = rgd->rd_length;
unsigned int x;
for (x = 0; x < length; x++) {
struct gfs2_bitmap *bi = rgd->rd_bits + x;
if (!bi->bi_clone)
continue;
if (sdp->sd_args.ar_discard)
gfs2_rgrp_send_discards(sdp, rgd->rd_data0, bi);
clear_bit(GBF_FULL, &bi->bi_flags);
memcpy(bi->bi_clone + bi->bi_offset,
bi->bi_bh->b_data + bi->bi_offset, bi->bi_len);
}
spin_lock(&sdp->sd_rindex_spin);
rgd->rd_free_clone = rgd->rd_free;
spin_unlock(&sdp->sd_rindex_spin);
}
/**
* gfs2_alloc_get - get the struct gfs2_alloc structure for an inode
* @ip: the incore GFS2 inode structure
*
* Returns: the struct gfs2_alloc
*/
struct gfs2_alloc *gfs2_alloc_get(struct gfs2_inode *ip)
{
BUG_ON(ip->i_alloc != NULL);
ip->i_alloc = kzalloc(sizeof(struct gfs2_alloc), GFP_KERNEL);
return ip->i_alloc;
}
/**
* try_rgrp_fit - See if a given reservation will fit in a given RG
* @rgd: the RG data
* @al: the struct gfs2_alloc structure describing the reservation
*
* If there's room for the requested blocks to be allocated from the RG:
* Sets the $al_rgd field in @al.
*
* Returns: 1 on success (it fits), 0 on failure (it doesn't fit)
*/
static int try_rgrp_fit(struct gfs2_rgrpd *rgd, struct gfs2_alloc *al)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
int ret = 0;
if (rgd->rd_flags & (GFS2_RGF_NOALLOC | GFS2_RDF_ERROR))
return 0;
spin_lock(&sdp->sd_rindex_spin);
if (rgd->rd_free_clone >= al->al_requested) {
al->al_rgd = rgd;
ret = 1;
}
spin_unlock(&sdp->sd_rindex_spin);
return ret;
}
/**
* try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes
* @rgd: The rgrp
*
* Returns: The inode, if one has been found
*/
static struct inode *try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked,
u64 skip)
{
struct inode *inode;
u32 goal = 0, block;
u64 no_addr;
struct gfs2_sbd *sdp = rgd->rd_sbd;
unsigned int n;
for(;;) {
if (goal >= rgd->rd_data)
break;
down_write(&sdp->sd_log_flush_lock);
n = 1;
block = rgblk_search(rgd, goal, GFS2_BLKST_UNLINKED,
GFS2_BLKST_UNLINKED, &n);
up_write(&sdp->sd_log_flush_lock);
if (block == BFITNOENT)
break;
/* rgblk_search can return a block < goal, so we need to
keep it marching forward. */
no_addr = block + rgd->rd_data0;
goal++;
if (*last_unlinked != NO_BLOCK && no_addr <= *last_unlinked)
continue;
if (no_addr == skip)
continue;
*last_unlinked = no_addr;
inode = gfs2_inode_lookup(rgd->rd_sbd->sd_vfs, DT_UNKNOWN,
no_addr, -1, 1);
if (!IS_ERR(inode))
return inode;
}
rgd->rd_flags &= ~GFS2_RDF_CHECK;
return NULL;
}
/**
* recent_rgrp_next - get next RG from "recent" list
* @cur_rgd: current rgrp
*
* Returns: The next rgrp in the recent list