fatfs: proper adjacent multicluster read/write

This commit is contained in:
Matheus
2026-07-09 18:21:45 -03:00
parent 6ffa178350
commit e91d82cf09
+29 -12
View File
@@ -80,28 +80,45 @@ int fatfs_rw_clusters_iovec(fatfs_t *fs, fatnode_t *node, iovec_iterator_t *iove
__assert(cluster && fatfs_is_cluster_eof(fs, cluster) == false);
for (uintmax_t i = 0; i < count; ++i) {
uintmax_t i = 0;
while (i < count) {
__assert(index + i < ROUND_UP(node->size, fs->cluster_size) / fs->cluster_size);
size_t cluster_count = 1;
fatfs_cluster_t last_cluster = cluster;
fatfs_cluster_t next_loop_cluster = 0;
while (i + cluster_count < count) {
fatfs_cluster_t next_cluster;
error = fatfs_next_cluster(fs, last_cluster, &next_cluster);
if (error)
return error;
__assert(next_cluster);
__assert(fatfs_is_cluster_eof(fs, next_cluster) == false);
if (next_cluster != last_cluster + 1) {
next_loop_cluster = next_cluster;
break;
}
last_cluster = next_cluster;
cluster_count += 1;
}
uintmax_t disk_offset = cluster_disk_offset(fs, cluster);
size_t byte_count = cluster_count * fs->cluster_size;
size_t done_count;
error = write ?
vfs_write_iovec(fs->backing, iovec_iterator, fs->cluster_size, disk_offset, &done_count, cache ? 0 : V_FFLAGS_NOCACHE) :
vfs_read_iovec(fs->backing, iovec_iterator, fs->cluster_size, disk_offset, &done_count, cache ? 0 : V_FFLAGS_NOCACHE);
vfs_write_iovec(fs->backing, iovec_iterator, byte_count, disk_offset, &done_count, cache ? 0 : V_FFLAGS_NOCACHE) :
vfs_read_iovec(fs->backing, iovec_iterator, byte_count, disk_offset, &done_count, cache ? 0 : V_FFLAGS_NOCACHE);
if (error)
return error;
__assert(done_count == fs->cluster_size);
__assert(done_count == byte_count);
i += cluster_count;
if (i + 1 != count) {
error = fatfs_next_cluster(fs, cluster, &cluster);
if (error)
return error;
__assert(cluster);
__assert(fatfs_is_cluster_eof(fs, cluster) == false);
}
cluster = next_loop_cluster;
}
return 0;