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Finish QCOW version 2 and stop making it conditional.

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We have a different ordering for the RC block(s) and L2 tables.
This is expected to be a non-issue, because everything is found
through file offsets in the corresponding RC table and L1 table.
Files that grow organically have RC blocks and L2 tables scattered
all over the place anyway.

The reason for the difference is that mkimg needs to be able to
write to a pipe. We can't seek forward and backward to fill in
the bits in non-sequential order.
This commit is contained in:
Marcel Moolenaar 2014-09-24 22:45:03 +00:00
parent cdcab7b62a
commit e187064261
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=272086
1 changed files with 67 additions and 45 deletions
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112
usr.bin/mkimg/qcow.c
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@ -40,8 +40,6 @@ __FBSDID("$FreeBSD$");
#include "format.h"
#include "mkimg.h"
#undef QCOW_SUPPORT_QCOW2
/* Default cluster sizes. */
#define QCOW1_CLSTR_LOG2SZ 12 /* 4KB */
#define QCOW2_CLSTR_LOG2SZ 16 /* 64KB */
@ -123,21 +121,19 @@ qcow1_resize(lba_t imgsz)
return (qcow_resize(imgsz, QCOW_VERSION_1));
}
#ifdef QCOW_SUPPORT_QCOW2
static int
qcow2_resize(lba_t imgsz)
{
return (qcow_resize(imgsz, QCOW_VERSION_2));
}
#endif
static int
qcow_write(int fd, u_int version)
{
struct qcow_header *hdr;
uint64_t *l1tbl, *l2tbl;
uint16_t *rctbl;
uint64_t *l1tbl, *l2tbl, *rctbl;
uint16_t *rcblk;
uint64_t clstr_imgsz, clstr_l2tbls, clstr_l1tblsz;
uint64_t clstr_rcblks, clstr_rctblsz;
uint64_t n, imagesz, nclstrs, ofs, ofsflags;
@ -170,13 +166,15 @@ qcow_write(int fd, u_int version)
* 0 - header
* 1 - L1 table
* 2 - RC table (v2 only)
* 3 - First RC block (v2 only)
* 4 - L2 tables
* n - data
* 3 - L2 tables
* 4 - RC block (v2 only)
* 5 - data
*/
l1clno = 1;
rcclno = 0;
rctbl = l2tbl = l1tbl = NULL;
rcblk = NULL;
hdr = calloc(1, clstrsz);
if (hdr == NULL)
@ -196,7 +194,7 @@ qcow_write(int fd, u_int version)
case QCOW_VERSION_2:
ofsflags = QCOW_CLSTR_COPIED;
rcclno = l1clno + clstr_l1tblsz;
l2clno = rcclno + clstr_rctblsz + 1;
l2clno = rcclno + clstr_rctblsz;
be32enc(&hdr->clstr_log2sz, clstr_log2sz);
be32enc(&hdr->u.v2.l1_entries, clstr_l2tbls);
be64enc(&hdr->u.v2.l1_offset, clstrsz * l1clno);
@ -207,52 +205,62 @@ qcow_write(int fd, u_int version)
return (EDOOFUS);
}
l2tbl = l1tbl = NULL;
rctbl = NULL;
if (sparse_write(fd, hdr, clstrsz) < 0) {
error = errno;
goto out;
}
free(hdr);
hdr = NULL;
ofs = clstrsz * l2clno;
nclstrs = 1 + clstr_l1tblsz + clstr_rctblsz;
l1tbl = calloc(1, clstrsz * clstr_l1tblsz);
if (l1tbl == NULL) {
error = ENOMEM;
goto out;
}
for (n = 0; n < clstr_imgsz; n++) {
blk = n * blk_clstrsz;
if (image_data(blk, blk_clstrsz)) {
nclstrs++;
l1idx = n >> (clstr_log2sz - 3);
if (l1tbl[l1idx] == 0) {
be64enc(l1tbl + l1idx, ofs + ofsflags);
ofs += clstrsz;
nclstrs++;
}
}
}
if (sparse_write(fd, l1tbl, clstrsz * clstr_l1tblsz) < 0) {
error = errno;
goto out;
}
clstr_rcblks = 0;
do {
n = clstr_rcblks;
clstr_rcblks = round_clstr((nclstrs + n) * 2) >> clstr_log2sz;
} while (n < clstr_rcblks);
if (rcclno > 0) {
rctbl = calloc(1, clstrsz * clstr_rctblsz);
if (rctbl == NULL) {
error = ENOMEM;
goto out;
}
}
ofs = clstrsz * l2clno;
for (n = 0; n < clstr_imgsz; n++) {
l1idx = n >> (clstr_log2sz - 3);
if (l1tbl[l1idx] != 0UL)
continue;
blk = n * blk_clstrsz;
if (image_data(blk, blk_clstrsz)) {
be64enc(l1tbl + l1idx, ofs + ofsflags);
for (n = 0; n < clstr_rcblks; n++) {
be64enc(rctbl + n, ofs);
ofs += clstrsz;
nclstrs++;
}
}
error = 0;
if (!error && sparse_write(fd, hdr, clstrsz) < 0)
error = errno;
if (!error && sparse_write(fd, l1tbl, clstrsz * clstr_l1tblsz) < 0)
error = errno;
if (rcclno > 0) {
if (!error &&
sparse_write(fd, rctbl, clstrsz * clstr_rctblsz) < 0)
if (sparse_write(fd, rctbl, clstrsz * clstr_rctblsz) < 0) {
error = errno;
if (!error && sparse_write(fd, rctbl, clstrsz) < 0)
error = errno;
}
if (error)
goto out;
free(hdr);
hdr = NULL;
if (rctbl != NULL) {
goto out;
}
free(rctbl);
rctbl = NULL;
}
@ -288,6 +296,22 @@ qcow_write(int fd, u_int version)
free(l1tbl);
l1tbl = NULL;
if (rcclno > 0) {
rcblk = calloc(1, clstrsz * clstr_rcblks);
if (rcblk == NULL) {
error = ENOMEM;
goto out;
}
for (n = 0; n < nclstrs; n++)
be16enc(rcblk + n, 1);
if (sparse_write(fd, rcblk, clstrsz * clstr_rcblks) < 0) {
error = errno;
goto out;
}
free(rcblk);
rcblk = NULL;
}
error = 0;
for (n = 0; n < clstr_imgsz; n++) {
blk = n * blk_clstrsz;
@ -301,6 +325,8 @@ qcow_write(int fd, u_int version)
error = image_copyout_done(fd);
out:
if (rcblk != NULL)
free(rcblk);
if (l2tbl != NULL)
free(l2tbl);
if (rctbl != NULL)
@ -319,14 +345,12 @@ qcow1_write(int fd)
return (qcow_write(fd, QCOW_VERSION_1));
}
#ifdef QCOW_SUPPORT_QCOW2
static int
qcow2_write(int fd)
{
return (qcow_write(fd, QCOW_VERSION_2));
}
#endif
static struct mkimg_format qcow1_format = {
.name = "qcow",
@ -336,7 +360,6 @@ static struct mkimg_format qcow1_format = {
};
FORMAT_DEFINE(qcow1_format);
#ifdef QCOW_SUPPORT_QCOW2
static struct mkimg_format qcow2_format = {
.name = "qcow2",
.description = "QEMU Copy-On-Write, version 2",
@ -344,4 +367,3 @@ static struct mkimg_format qcow2_format = {
.write = qcow2_write,
};
FORMAT_DEFINE(qcow2_format);
#endif