gfs2-utils/bz1942434-1-gfs2_jadd_Use_fallocate_to_preallocate_journals.patch

80 lines
1.9 KiB
Diff

commit 13e09a3519cc7cbf9417acc86a6d046bdba71a9f
Author: Andrew Price <anprice@redhat.com>
Date: Thu Mar 18 17:30:53 2021 +0000
gfs2_jadd: Use fallocate to preallocate journals
Fall back to writes for ancient kernels and use larger writes in that
case to reduce the chance of fragmentation.
Resolves: rhbz#1942434
Signed-off-by: Andrew Price <anprice@redhat.com>
diff --git a/gfs2/mkfs/main_jadd.c b/gfs2/mkfs/main_jadd.c
index ea89c96b..b0cffbac 100644
--- a/gfs2/mkfs/main_jadd.c
+++ b/gfs2/mkfs/main_jadd.c
@@ -474,6 +474,43 @@ static uint64_t find_block_address(int fd, off_t offset, unsigned bsize)
}
#endif
+static int alloc_new_journal(int fd, unsigned bytes)
+{
+#define ALLOC_BUF_SIZE (4 << 20)
+ unsigned left = bytes;
+ int error;
+ char *buf;
+
+ error = fallocate(fd, 0, 0, bytes);
+ if (error == 0)
+ return 0;
+ if (errno != EOPNOTSUPP)
+ goto out_errno;
+
+ /* No fallocate support, fall back to writes */
+ buf = calloc(1, ALLOC_BUF_SIZE);
+ if (buf == NULL)
+ goto out_errno;
+
+ while (left > 0) {
+ unsigned sz = ALLOC_BUF_SIZE;
+
+ if (left < ALLOC_BUF_SIZE)
+ sz = left;
+
+ if (pwrite(fd, buf, sz, bytes - left) != sz) {
+ free(buf);
+ goto out_errno;
+ }
+ left -= sz;
+ }
+ free(buf);
+ return 0;
+out_errno:
+ perror("Failed to allocate space for new journal");
+ return -1;
+}
+
static int add_j(struct gfs2_sbd *sdp, struct jadd_opts *opts)
{
int fd, error = 0;
@@ -490,14 +527,9 @@ static int add_j(struct gfs2_sbd *sdp, struct jadd_opts *opts)
if ((error = set_flags(fd, JA_FL_CLEAR, FS_JOURNAL_DATA_FL)))
goto close_fd;
- memset(buf, 0, sdp->bsize);
- for (x=0; x<blocks; x++) {
- if (write(fd, buf, sdp->bsize) != sdp->bsize) {
- perror("add_j write");
- error = -1;
- goto close_fd;
- }
- }
+ error = alloc_new_journal(fd, sdp->jsize << 20);
+ if (error != 0)
+ goto close_fd;
if ((error = lseek(fd, 0, SEEK_SET)) < 0) {
perror("add_j lseek");