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|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_trans.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_rtbitmap.h"
/*
* Realtime allocator bitmap functions shared with userspace.
*/
/*
* Real time buffers need verifiers to avoid runtime warnings during IO.
* We don't have anything to verify, however, so these are just dummy
* operations.
*/
static void
xfs_rtbuf_verify_read(
struct xfs_buf *bp)
{
return;
}
static void
xfs_rtbuf_verify_write(
struct xfs_buf *bp)
{
return;
}
const struct xfs_buf_ops xfs_rtbuf_ops = {
.name = "rtbuf",
.verify_read = xfs_rtbuf_verify_read,
.verify_write = xfs_rtbuf_verify_write,
};
/* Release cached rt bitmap and summary buffers. */
void
xfs_rtbuf_cache_relse(
struct xfs_rtalloc_args *args)
{
if (args->rbmbp) {
xfs_trans_brelse(args->tp, args->rbmbp);
args->rbmbp = NULL;
args->rbmoff = NULLFILEOFF;
}
if (args->sumbp) {
xfs_trans_brelse(args->tp, args->sumbp);
args->sumbp = NULL;
args->sumoff = NULLFILEOFF;
}
}
/*
* Get a buffer for the bitmap or summary file block specified.
* The buffer is returned read and locked.
*/
int
xfs_rtbuf_get(
struct xfs_rtalloc_args *args,
xfs_fileoff_t block, /* block number in bitmap or summary */
int issum) /* is summary not bitmap */
{
struct xfs_mount *mp = args->mp;
struct xfs_buf **cbpp; /* cached block buffer */
xfs_fileoff_t *coffp; /* cached block number */
struct xfs_buf *bp; /* block buffer, result */
struct xfs_inode *ip; /* bitmap or summary inode */
struct xfs_bmbt_irec map;
enum xfs_blft type;
int nmap = 1;
int error;
if (issum) {
cbpp = &args->sumbp;
coffp = &args->sumoff;
ip = mp->m_rsumip;
type = XFS_BLFT_RTSUMMARY_BUF;
} else {
cbpp = &args->rbmbp;
coffp = &args->rbmoff;
ip = mp->m_rbmip;
type = XFS_BLFT_RTBITMAP_BUF;
}
/*
* If we have a cached buffer, and the block number matches, use that.
*/
if (*cbpp && *coffp == block)
return 0;
/*
* Otherwise we have to have to get the buffer. If there was an old
* one, get rid of it first.
*/
if (*cbpp) {
xfs_trans_brelse(args->tp, *cbpp);
*cbpp = NULL;
}
error = xfs_bmapi_read(ip, block, 1, &map, &nmap, 0);
if (error)
return error;
if (XFS_IS_CORRUPT(mp, nmap == 0 || !xfs_bmap_is_written_extent(&map)))
return -EFSCORRUPTED;
ASSERT(map.br_startblock != NULLFSBLOCK);
error = xfs_trans_read_buf(mp, args->tp, mp->m_ddev_targp,
XFS_FSB_TO_DADDR(mp, map.br_startblock),
mp->m_bsize, 0, &bp, &xfs_rtbuf_ops);
if (error)
return error;
xfs_trans_buf_set_type(args->tp, bp, type);
*cbpp = bp;
*coffp = block;
return 0;
}
/*
* Searching backward from start to limit, find the first block whose
* allocated/free state is different from start's.
*/
int
xfs_rtfind_back(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext to look at */
xfs_rtxnum_t limit, /* last rtext to look at */
xfs_rtxnum_t *rtx) /* out: start rtext found */
{
struct xfs_mount *mp = args->mp;
int bit; /* bit number in the word */
xfs_fileoff_t block; /* bitmap block number */
int error; /* error value */
xfs_rtxnum_t firstbit; /* first useful bit in the word */
xfs_rtxnum_t i; /* current bit number rel. to start */
xfs_rtxnum_t len; /* length of inspected area */
xfs_rtword_t mask; /* mask of relevant bits for value */
xfs_rtword_t want; /* mask for "good" values */
xfs_rtword_t wdiff; /* difference from wanted value */
xfs_rtword_t incore;
unsigned int word; /* word number in the buffer */
/*
* Compute and read in starting bitmap block for starting block.
*/
block = xfs_rtx_to_rbmblock(mp, start);
error = xfs_rtbitmap_read_buf(args, block);
if (error)
return error;
/*
* Get the first word's index & point to it.
*/
word = xfs_rtx_to_rbmword(mp, start);
bit = (int)(start & (XFS_NBWORD - 1));
len = start - limit + 1;
/*
* Compute match value, based on the bit at start: if 1 (free)
* then all-ones, else all-zeroes.
*/
incore = xfs_rtbitmap_getword(args, word);
want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
/*
* If the starting position is not word-aligned, deal with the
* partial word.
*/
if (bit < XFS_NBWORD - 1) {
/*
* Calculate first (leftmost) bit number to look at,
* and mask for all the relevant bits in this word.
*/
firstbit = XFS_RTMAX((xfs_srtblock_t)(bit - len + 1), 0);
mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
firstbit;
/*
* Calculate the difference between the value there
* and what we're looking for.
*/
if ((wdiff = (incore ^ want) & mask)) {
/*
* Different. Mark where we are and return.
*/
i = bit - XFS_RTHIBIT(wdiff);
*rtx = start - i + 1;
return 0;
}
i = bit - firstbit + 1;
/*
* Go on to previous block if that's where the previous word is
* and we need the previous word.
*/
if (--word == -1 && i < len) {
/*
* If done with this block, get the previous one.
*/
error = xfs_rtbitmap_read_buf(args, --block);
if (error)
return error;
word = mp->m_blockwsize - 1;
}
} else {
/*
* Starting on a word boundary, no partial word.
*/
i = 0;
}
/*
* Loop over whole words in buffers. When we use up one buffer
* we move on to the previous one.
*/
while (len - i >= XFS_NBWORD) {
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = incore ^ want)) {
/*
* Different, mark where we are and return.
*/
i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
*rtx = start - i + 1;
return 0;
}
i += XFS_NBWORD;
/*
* Go on to previous block if that's where the previous word is
* and we need the previous word.
*/
if (--word == -1 && i < len) {
/*
* If done with this block, get the previous one.
*/
error = xfs_rtbitmap_read_buf(args, --block);
if (error)
return error;
word = mp->m_blockwsize - 1;
}
}
/*
* If not ending on a word boundary, deal with the last
* (partial) word.
*/
if (len - i) {
/*
* Calculate first (leftmost) bit number to look at,
* and mask for all the relevant bits in this word.
*/
firstbit = XFS_NBWORD - (len - i);
mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = (incore ^ want) & mask)) {
/*
* Different, mark where we are and return.
*/
i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
*rtx = start - i + 1;
return 0;
} else
i = len;
}
/*
* No match, return that we scanned the whole area.
*/
*rtx = start - i + 1;
return 0;
}
/*
* Searching forward from start to limit, find the first block whose
* allocated/free state is different from start's.
*/
int
xfs_rtfind_forw(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext to look at */
xfs_rtxnum_t limit, /* last rtext to look at */
xfs_rtxnum_t *rtx) /* out: start rtext found */
{
struct xfs_mount *mp = args->mp;
int bit; /* bit number in the word */
xfs_fileoff_t block; /* bitmap block number */
int error;
xfs_rtxnum_t i; /* current bit number rel. to start */
xfs_rtxnum_t lastbit;/* last useful bit in the word */
xfs_rtxnum_t len; /* length of inspected area */
xfs_rtword_t mask; /* mask of relevant bits for value */
xfs_rtword_t want; /* mask for "good" values */
xfs_rtword_t wdiff; /* difference from wanted value */
xfs_rtword_t incore;
unsigned int word; /* word number in the buffer */
/*
* Compute and read in starting bitmap block for starting block.
*/
block = xfs_rtx_to_rbmblock(mp, start);
error = xfs_rtbitmap_read_buf(args, block);
if (error)
return error;
/*
* Get the first word's index & point to it.
*/
word = xfs_rtx_to_rbmword(mp, start);
bit = (int)(start & (XFS_NBWORD - 1));
len = limit - start + 1;
/*
* Compute match value, based on the bit at start: if 1 (free)
* then all-ones, else all-zeroes.
*/
incore = xfs_rtbitmap_getword(args, word);
want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
/*
* If the starting position is not word-aligned, deal with the
* partial word.
*/
if (bit) {
/*
* Calculate last (rightmost) bit number to look at,
* and mask for all the relevant bits in this word.
*/
lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
/*
* Calculate the difference between the value there
* and what we're looking for.
*/
if ((wdiff = (incore ^ want) & mask)) {
/*
* Different. Mark where we are and return.
*/
i = XFS_RTLOBIT(wdiff) - bit;
*rtx = start + i - 1;
return 0;
}
i = lastbit - bit;
/*
* Go on to next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* If done with this block, get the previous one.
*/
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
word = 0;
}
} else {
/*
* Starting on a word boundary, no partial word.
*/
i = 0;
}
/*
* Loop over whole words in buffers. When we use up one buffer
* we move on to the next one.
*/
while (len - i >= XFS_NBWORD) {
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = incore ^ want)) {
/*
* Different, mark where we are and return.
*/
i += XFS_RTLOBIT(wdiff);
*rtx = start + i - 1;
return 0;
}
i += XFS_NBWORD;
/*
* Go on to next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* If done with this block, get the next one.
*/
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
word = 0;
}
}
/*
* If not ending on a word boundary, deal with the last
* (partial) word.
*/
if ((lastbit = len - i)) {
/*
* Calculate mask for all the relevant bits in this word.
*/
mask = ((xfs_rtword_t)1 << lastbit) - 1;
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = (incore ^ want) & mask)) {
/*
* Different, mark where we are and return.
*/
i += XFS_RTLOBIT(wdiff);
*rtx = start + i - 1;
return 0;
} else
i = len;
}
/*
* No match, return that we scanned the whole area.
*/
*rtx = start + i - 1;
return 0;
}
/* Log rtsummary counter at @infoword. */
static inline void
xfs_trans_log_rtsummary(
struct xfs_rtalloc_args *args,
unsigned int infoword)
{
struct xfs_buf *bp = args->sumbp;
size_t first, last;
first = (void *)xfs_rsumblock_infoptr(args, infoword) - bp->b_addr;
last = first + sizeof(xfs_suminfo_t) - 1;
xfs_trans_log_buf(args->tp, bp, first, last);
}
/*
* Modify the summary information for a given extent size, bitmap block
* combination.
*/
int
xfs_rtmodify_summary(
struct xfs_rtalloc_args *args,
int log, /* log2 of extent size */
xfs_fileoff_t bbno, /* bitmap block number */
int delta) /* in/out: summary block number */
{
struct xfs_mount *mp = args->mp;
xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
unsigned int infoword;
xfs_suminfo_t val;
int error;
error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
if (error)
return error;
infoword = xfs_rtsumoffs_to_infoword(mp, so);
val = xfs_suminfo_add(args, infoword, delta);
if (mp->m_rsum_cache) {
if (val == 0 && log + 1 == mp->m_rsum_cache[bbno])
mp->m_rsum_cache[bbno] = log;
if (val != 0 && log >= mp->m_rsum_cache[bbno])
mp->m_rsum_cache[bbno] = log + 1;
}
xfs_trans_log_rtsummary(args, infoword);
return 0;
}
/*
* Read and return the summary information for a given extent size, bitmap block
* combination.
*/
int
xfs_rtget_summary(
struct xfs_rtalloc_args *args,
int log, /* log2 of extent size */
xfs_fileoff_t bbno, /* bitmap block number */
xfs_suminfo_t *sum) /* out: summary info for this block */
{
struct xfs_mount *mp = args->mp;
xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
int error;
error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
if (!error)
*sum = xfs_suminfo_get(args, xfs_rtsumoffs_to_infoword(mp, so));
return error;
}
/* Log rtbitmap block from the word @from to the byte before @next. */
static inline void
xfs_trans_log_rtbitmap(
struct xfs_rtalloc_args *args,
unsigned int from,
unsigned int next)
{
struct xfs_buf *bp = args->rbmbp;
size_t first, last;
first = (void *)xfs_rbmblock_wordptr(args, from) - bp->b_addr;
last = ((void *)xfs_rbmblock_wordptr(args, next) - 1) - bp->b_addr;
xfs_trans_log_buf(args->tp, bp, first, last);
}
/*
* Set the given range of bitmap bits to the given value.
* Do whatever I/O and logging is required.
*/
int
xfs_rtmodify_range(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext to modify */
xfs_rtxlen_t len, /* length of extent to modify */
int val) /* 1 for free, 0 for allocated */
{
struct xfs_mount *mp = args->mp;
int bit; /* bit number in the word */
xfs_fileoff_t block; /* bitmap block number */
int error;
int i; /* current bit number rel. to start */
int lastbit; /* last useful bit in word */
xfs_rtword_t mask; /* mask of relevant bits for value */
xfs_rtword_t incore;
unsigned int firstword; /* first word used in the buffer */
unsigned int word; /* word number in the buffer */
/*
* Compute starting bitmap block number.
*/
block = xfs_rtx_to_rbmblock(mp, start);
/*
* Read the bitmap block, and point to its data.
*/
error = xfs_rtbitmap_read_buf(args, block);
if (error)
return error;
/*
* Compute the starting word's address, and starting bit.
*/
firstword = word = xfs_rtx_to_rbmword(mp, start);
bit = (int)(start & (XFS_NBWORD - 1));
/*
* 0 (allocated) => all zeroes; 1 (free) => all ones.
*/
val = -val;
/*
* If not starting on a word boundary, deal with the first
* (partial) word.
*/
if (bit) {
/*
* Compute first bit not changed and mask of relevant bits.
*/
lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
/*
* Set/clear the active bits.
*/
incore = xfs_rtbitmap_getword(args, word);
if (val)
incore |= mask;
else
incore &= ~mask;
xfs_rtbitmap_setword(args, word, incore);
i = lastbit - bit;
/*
* Go on to the next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* Log the changed part of this block.
* Get the next one.
*/
xfs_trans_log_rtbitmap(args, firstword, word);
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
firstword = word = 0;
}
} else {
/*
* Starting on a word boundary, no partial word.
*/
i = 0;
}
/*
* Loop over whole words in buffers. When we use up one buffer
* we move on to the next one.
*/
while (len - i >= XFS_NBWORD) {
/*
* Set the word value correctly.
*/
xfs_rtbitmap_setword(args, word, val);
i += XFS_NBWORD;
/*
* Go on to the next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* Log the changed part of this block.
* Get the next one.
*/
xfs_trans_log_rtbitmap(args, firstword, word);
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
firstword = word = 0;
}
}
/*
* If not ending on a word boundary, deal with the last
* (partial) word.
*/
if ((lastbit = len - i)) {
/*
* Compute a mask of relevant bits.
*/
mask = ((xfs_rtword_t)1 << lastbit) - 1;
/*
* Set/clear the active bits.
*/
incore = xfs_rtbitmap_getword(args, word);
if (val)
incore |= mask;
else
incore &= ~mask;
xfs_rtbitmap_setword(args, word, incore);
word++;
}
/*
* Log any remaining changed bytes.
*/
if (word > firstword)
xfs_trans_log_rtbitmap(args, firstword, word);
return 0;
}
/*
* Mark an extent specified by start and len freed.
* Updates all the summary information as well as the bitmap.
*/
int
xfs_rtfree_range(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext to free */
xfs_rtxlen_t len) /* in/out: summary block number */
{
struct xfs_mount *mp = args->mp;
xfs_rtxnum_t end; /* end of the freed extent */
int error; /* error value */
xfs_rtxnum_t postblock; /* first rtext freed > end */
xfs_rtxnum_t preblock; /* first rtext freed < start */
end = start + len - 1;
/*
* Modify the bitmap to mark this extent freed.
*/
error = xfs_rtmodify_range(args, start, len, 1);
if (error) {
return error;
}
/*
* Assume we're freeing out of the middle of an allocated extent.
* We need to find the beginning and end of the extent so we can
* properly update the summary.
*/
error = xfs_rtfind_back(args, start, 0, &preblock);
if (error) {
return error;
}
/*
* Find the next allocated block (end of allocated extent).
*/
error = xfs_rtfind_forw(args, end, mp->m_sb.sb_rextents - 1,
&postblock);
if (error)
return error;
/*
* If there are blocks not being freed at the front of the
* old extent, add summary data for them to be allocated.
*/
if (preblock < start) {
error = xfs_rtmodify_summary(args,
XFS_RTBLOCKLOG(start - preblock),
xfs_rtx_to_rbmblock(mp, preblock), -1);
if (error) {
return error;
}
}
/*
* If there are blocks not being freed at the end of the
* old extent, add summary data for them to be allocated.
*/
if (postblock > end) {
error = xfs_rtmodify_summary(args,
XFS_RTBLOCKLOG(postblock - end),
xfs_rtx_to_rbmblock(mp, end + 1), -1);
if (error) {
return error;
}
}
/*
* Increment the summary information corresponding to the entire
* (new) free extent.
*/
return xfs_rtmodify_summary(args,
XFS_RTBLOCKLOG(postblock + 1 - preblock),
xfs_rtx_to_rbmblock(mp, preblock), 1);
}
/*
* Check that the given range is either all allocated (val = 0) or
* all free (val = 1).
*/
int
xfs_rtcheck_range(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext number of extent */
xfs_rtxlen_t len, /* length of extent */
int val, /* 1 for free, 0 for allocated */
xfs_rtxnum_t *new, /* out: first rtext not matching */
int *stat) /* out: 1 for matches, 0 for not */
{
struct xfs_mount *mp = args->mp;
int bit; /* bit number in the word */
xfs_fileoff_t block; /* bitmap block number */
int error;
xfs_rtxnum_t i; /* current bit number rel. to start */
xfs_rtxnum_t lastbit; /* last useful bit in word */
xfs_rtword_t mask; /* mask of relevant bits for value */
xfs_rtword_t wdiff; /* difference from wanted value */
xfs_rtword_t incore;
unsigned int word; /* word number in the buffer */
/*
* Compute starting bitmap block number
*/
block = xfs_rtx_to_rbmblock(mp, start);
/*
* Read the bitmap block.
*/
error = xfs_rtbitmap_read_buf(args, block);
if (error)
return error;
/*
* Compute the starting word's address, and starting bit.
*/
word = xfs_rtx_to_rbmword(mp, start);
bit = (int)(start & (XFS_NBWORD - 1));
/*
* 0 (allocated) => all zero's; 1 (free) => all one's.
*/
val = -val;
/*
* If not starting on a word boundary, deal with the first
* (partial) word.
*/
if (bit) {
/*
* Compute first bit not examined.
*/
lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
/*
* Mask of relevant bits.
*/
mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = (incore ^ val) & mask)) {
/*
* Different, compute first wrong bit and return.
*/
i = XFS_RTLOBIT(wdiff) - bit;
*new = start + i;
*stat = 0;
return 0;
}
i = lastbit - bit;
/*
* Go on to next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* If done with this block, get the next one.
*/
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
word = 0;
}
} else {
/*
* Starting on a word boundary, no partial word.
*/
i = 0;
}
/*
* Loop over whole words in buffers. When we use up one buffer
* we move on to the next one.
*/
while (len - i >= XFS_NBWORD) {
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = incore ^ val)) {
/*
* Different, compute first wrong bit and return.
*/
i += XFS_RTLOBIT(wdiff);
*new = start + i;
*stat = 0;
return 0;
}
i += XFS_NBWORD;
/*
* Go on to next block if that's where the next word is
* and we need the next word.
*/
if (++word == mp->m_blockwsize && i < len) {
/*
* If done with this block, get the next one.
*/
error = xfs_rtbitmap_read_buf(args, ++block);
if (error)
return error;
word = 0;
}
}
/*
* If not ending on a word boundary, deal with the last
* (partial) word.
*/
if ((lastbit = len - i)) {
/*
* Mask of relevant bits.
*/
mask = ((xfs_rtword_t)1 << lastbit) - 1;
/*
* Compute difference between actual and desired value.
*/
incore = xfs_rtbitmap_getword(args, word);
if ((wdiff = (incore ^ val) & mask)) {
/*
* Different, compute first wrong bit and return.
*/
i += XFS_RTLOBIT(wdiff);
*new = start + i;
*stat = 0;
return 0;
} else
i = len;
}
/*
* Successful, return.
*/
*new = start + i;
*stat = 1;
return 0;
}
#ifdef DEBUG
/*
* Check that the given extent (block range) is allocated already.
*/
STATIC int
xfs_rtcheck_alloc_range(
struct xfs_rtalloc_args *args,
xfs_rtxnum_t start, /* starting rtext number of extent */
xfs_rtxlen_t len) /* length of extent */
{
xfs_rtxnum_t new; /* dummy for xfs_rtcheck_range */
int stat;
int error;
error = xfs_rtcheck_range(args, start, len, 0, &new, &stat);
if (error)
return error;
ASSERT(stat);
return 0;
}
#else
#define xfs_rtcheck_alloc_range(a,b,l) (0)
#endif
/*
* Free an extent in the realtime subvolume. Length is expressed in
* realtime extents, as is the block number.
*/
int
xfs_rtfree_extent(
struct xfs_trans *tp, /* transaction pointer */
xfs_rtxnum_t start, /* starting rtext number to free */
xfs_rtxlen_t len) /* length of extent freed */
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_rtalloc_args args = {
.mp = mp,
.tp = tp,
};
int error;
struct timespec64 atime;
ASSERT(mp->m_rbmip->i_itemp != NULL);
ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
error = xfs_rtcheck_alloc_range(&args, start, len);
if (error)
return error;
/*
* Free the range of realtime blocks.
*/
error = xfs_rtfree_range(&args, start, len);
if (error)
goto out;
/*
* Mark more blocks free in the superblock.
*/
xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
/*
* If we've now freed all the blocks, reset the file sequence
* number to 0.
*/
if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
mp->m_sb.sb_rextents) {
if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM))
mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
atime = inode_get_atime(VFS_I(mp->m_rbmip));
atime.tv_sec = 0;
inode_set_atime_to_ts(VFS_I(mp->m_rbmip), atime);
xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
}
error = 0;
out:
xfs_rtbuf_cache_relse(&args);
return error;
}
/*
* Free some blocks in the realtime subvolume. rtbno and rtlen are in units of
* rt blocks, not rt extents; must be aligned to the rt extent size; and rtlen
* cannot exceed XFS_MAX_BMBT_EXTLEN.
*/
int
xfs_rtfree_blocks(
struct xfs_trans *tp,
xfs_fsblock_t rtbno,
xfs_filblks_t rtlen)
{
struct xfs_mount *mp = tp->t_mountp;
xfs_rtxnum_t start;
xfs_filblks_t len;
xfs_extlen_t mod;
ASSERT(rtlen <= XFS_MAX_BMBT_EXTLEN);
len = xfs_rtb_to_rtxrem(mp, rtlen, &mod);
if (mod) {
ASSERT(mod == 0);
return -EIO;
}
start = xfs_rtb_to_rtxrem(mp, rtbno, &mod);
if (mod) {
ASSERT(mod == 0);
return -EIO;
}
return xfs_rtfree_extent(tp, start, len);
}
/* Find all the free records within a given range. */
int
xfs_rtalloc_query_range(
struct xfs_mount *mp,
struct xfs_trans *tp,
const struct xfs_rtalloc_rec *low_rec,
const struct xfs_rtalloc_rec *high_rec,
xfs_rtalloc_query_range_fn fn,
void *priv)
{
struct xfs_rtalloc_args args = {
.mp = mp,
.tp = tp,
};
struct xfs_rtalloc_rec rec;
xfs_rtxnum_t rtstart;
xfs_rtxnum_t rtend;
xfs_rtxnum_t high_key;
int is_free;
int error = 0;
if (low_rec->ar_startext > high_rec->ar_startext)
return -EINVAL;
if (low_rec->ar_startext >= mp->m_sb.sb_rextents ||
low_rec->ar_startext == high_rec->ar_startext)
return 0;
high_key = min(high_rec->ar_startext, mp->m_sb.sb_rextents - 1);
/* Iterate the bitmap, looking for discrepancies. */
rtstart = low_rec->ar_startext;
while (rtstart <= high_key) {
/* Is the first block free? */
error = xfs_rtcheck_range(&args, rtstart, 1, 1, &rtend,
&is_free);
if (error)
break;
/* How long does the extent go for? */
error = xfs_rtfind_forw(&args, rtstart, high_key, &rtend);
if (error)
break;
if (is_free) {
rec.ar_startext = rtstart;
rec.ar_extcount = rtend - rtstart + 1;
error = fn(mp, tp, &rec, priv);
if (error)
break;
}
rtstart = rtend + 1;
}
xfs_rtbuf_cache_relse(&args);
return error;
}
/* Find all the free records. */
int
xfs_rtalloc_query_all(
struct xfs_mount *mp,
struct xfs_trans *tp,
xfs_rtalloc_query_range_fn fn,
void *priv)
{
struct xfs_rtalloc_rec keys[2];
keys[0].ar_startext = 0;
keys[1].ar_startext = mp->m_sb.sb_rextents - 1;
keys[0].ar_extcount = keys[1].ar_extcount = 0;
return xfs_rtalloc_query_range(mp, tp, &keys[0], &keys[1], fn, priv);
}
/* Is the given extent all free? */
int
xfs_rtalloc_extent_is_free(
struct xfs_mount *mp,
struct xfs_trans *tp,
xfs_rtxnum_t start,
xfs_rtxlen_t len,
bool *is_free)
{
struct xfs_rtalloc_args args = {
.mp = mp,
.tp = tp,
};
xfs_rtxnum_t end;
int matches;
int error;
error = xfs_rtcheck_range(&args, start, len, 1, &end, &matches);
xfs_rtbuf_cache_relse(&args);
if (error)
return error;
*is_free = matches;
return 0;
}
/*
* Compute the number of rtbitmap blocks needed to track the given number of rt
* extents.
*/
xfs_filblks_t
xfs_rtbitmap_blockcount(
struct xfs_mount *mp,
xfs_rtbxlen_t rtextents)
{
return howmany_64(rtextents, NBBY * mp->m_sb.sb_blocksize);
}
/*
* Compute the maximum level number of the realtime summary file, as defined by
* mkfs. The historic use of highbit32 on a 64-bit quantity prohibited correct
* use of rt volumes with more than 2^32 extents.
*/
uint8_t
xfs_compute_rextslog(
xfs_rtbxlen_t rtextents)
{
if (!rtextents)
return 0;
return xfs_highbit64(rtextents);
}
/*
* Compute the number of rtbitmap words needed to populate every block of a
* bitmap that is large enough to track the given number of rt extents.
*/
unsigned long long
xfs_rtbitmap_wordcount(
struct xfs_mount *mp,
xfs_rtbxlen_t rtextents)
{
xfs_filblks_t blocks;
blocks = xfs_rtbitmap_blockcount(mp, rtextents);
return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
}
/* Compute the number of rtsummary blocks needed to track the given rt space. */
xfs_filblks_t
xfs_rtsummary_blockcount(
struct xfs_mount *mp,
unsigned int rsumlevels,
xfs_extlen_t rbmblocks)
{
unsigned long long rsumwords;
rsumwords = (unsigned long long)rsumlevels * rbmblocks;
return XFS_B_TO_FSB(mp, rsumwords << XFS_WORDLOG);
}
/*
* Compute the number of rtsummary info words needed to populate every block of
* a summary file that is large enough to track the given rt space.
*/
unsigned long long
xfs_rtsummary_wordcount(
struct xfs_mount *mp,
unsigned int rsumlevels,
xfs_extlen_t rbmblocks)
{
xfs_filblks_t blocks;
blocks = xfs_rtsummary_blockcount(mp, rsumlevels, rbmblocks);
return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
}
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