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authorMarvin Borner2021-05-20 16:39:40 +0200
committerMarvin Borner2021-05-20 16:39:40 +0200
commit32a5fcaa8e082b7c27f46f1adf577ceb3d71ba7d (patch)
tree1792347be27873b5642b131445e4588772b2b634
parent9da2af6699ca6e954bc3cb523dd74a9195a503d5 (diff)
Removed useless allocations in FS reader
Diffstat
-rw-r--r--kernel/features/fs.c68
1 files changed, 29 insertions, 39 deletions
diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index dc8c071..f59d20c 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -214,48 +214,41 @@ CLEAR void vfs_install(void)
* EXT2
*/
-// TODO: Remove malloc from ext2_buffer_read (attempt in #56cd63f199)
-static void *ext2_buffer_read(u32 block, struct vfs_dev *dev)
+static void ext2_buffer_read(u32 block, void *buf, struct vfs_dev *dev)
{
- void *buf = zalloc(BLOCK_SIZE);
dev->read(buf, block * SECTOR_COUNT, SECTOR_COUNT, dev);
- return buf;
}
-static struct ext2_superblock *ext2_get_superblock(struct vfs_dev *dev)
+static void ext2_get_superblock(struct ext2_superblock *buf, struct vfs_dev *dev)
{
- struct ext2_superblock *sb = ext2_buffer_read(EXT2_SUPER, dev);
+ u8 data[BLOCK_SIZE] = { 0 };
+ ext2_buffer_read(EXT2_SUPER, data, dev);
+ memcpy(buf, data, sizeof(*buf));
- assert(sb->magic == EXT2_MAGIC);
- return sb;
-}
-
-static struct ext2_bgd *ext2_get_bgd(struct vfs_dev *dev)
-{
- return ext2_buffer_read(EXT2_SUPER + 1, dev);
+ assert(buf->magic == EXT2_MAGIC);
}
static struct ext2_inode *ext2_get_inode(u32 i, struct ext2_inode *in_buf, struct vfs_dev *dev)
{
- struct ext2_superblock *s = ext2_get_superblock(dev);
- assert(s);
- struct ext2_bgd *b = ext2_get_bgd(dev);
+ struct ext2_superblock sb = { 0 };
+ ext2_get_superblock(&sb, dev);
- u32 block_group = (i - 1) / s->inodes_per_group;
- u32 index = (i - 1) % s->inodes_per_group;
+ u8 data[BLOCK_SIZE] = { 0 };
+ ext2_buffer_read(EXT2_SUPER + 1, data, dev);
+ struct ext2_bgd *bgd = (struct ext2_bgd *)data;
+
+ u32 block_group = (i - 1) / sb.inodes_per_group;
+ u32 index = (i - 1) % sb.inodes_per_group;
u32 block = (index * EXT2_INODE_SIZE) / BLOCK_SIZE;
- b += block_group;
- assert(b);
+ bgd += block_group;
- u32 *buf = ext2_buffer_read(b->inode_table + block, dev);
+ u8 buf[BLOCK_SIZE] = { 0 };
+ ext2_buffer_read(bgd->inode_table + block, buf, dev);
struct ext2_inode *in =
(struct ext2_inode *)((u32)buf +
(index % (BLOCK_SIZE / EXT2_INODE_SIZE)) * EXT2_INODE_SIZE);
memcpy(in_buf, in, sizeof(*in_buf));
- free(buf);
- free(s);
- free(b - block_group);
return in_buf;
}
@@ -281,13 +274,13 @@ static u32 ext2_read_indirect(u32 indirect, u32 block_num, struct vfs_dev *dev)
}
if (!data) {
- data = ext2_buffer_read(indirect, dev);
+ u8 buf[BLOCK_SIZE] = { 0 };
+ ext2_buffer_read(indirect, buf, dev);
struct indirect_cache *cache = malloc(sizeof(*cache));
cache->block = indirect;
- memcpy(cache->data, data, BLOCK_SIZE);
+ memcpy(cache->data, buf, BLOCK_SIZE);
list_add(indirect_cache, cache);
- u32 ind = *(u32 *)((u32)data + block_num * sizeof(u32));
- free(data);
+ u32 ind = *(u32 *)((u32)buf + block_num * sizeof(u32));
return ind;
}
@@ -335,7 +328,8 @@ static res ext2_read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 cou
(i - (BLOCK_COUNT + 12)) % BLOCK_COUNT, dev);
}
- char *data = ext2_buffer_read(blocknum, dev);
+ u8 data[BLOCK_SIZE] = { 0 };
+ ext2_buffer_read(blocknum, data, dev);
u32 block_offset = (i == first_block) ? first_block_offset : 0;
u32 byte_count = MIN(BLOCK_SIZE - block_offset, remaining);
@@ -344,7 +338,6 @@ static res ext2_read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 cou
copied += byte_count;
remaining -= byte_count;
- free(data);
/* printf("Loaded %d of %d\n", i + 1, last_block); */
}
@@ -370,13 +363,12 @@ static u32 ext2_find_inode(const char *name, u32 dir_inode, struct vfs_dev *dev)
struct ext2_inode i = { 0 };
ext2_get_inode(dir_inode, &i, dev);
- char *buf = malloc(BLOCK_SIZE * i.blocks / 2);
- memset(buf, 0, BLOCK_SIZE * i.blocks / 2);
+ char *buf = zalloc(BLOCK_SIZE * i.blocks / 2);
+ u8 data[BLOCK_SIZE] = { 0 };
for (u32 q = 0; q < i.blocks / 2; q++) {
- char *data = ext2_buffer_read(i.block[q], dev);
+ ext2_buffer_read(i.block[q], data, dev);
memcpy((u32 *)((u32)buf + q * BLOCK_SIZE), data, BLOCK_SIZE);
- free(data);
}
struct ext2_dirent *d = (struct ext2_dirent *)buf;
@@ -485,11 +477,10 @@ static res ext2_perm(const char *path, enum vfs_perm perm, struct vfs_dev *dev)
CLEAR u8 ext2_load(struct vfs_dev *dev)
{
- struct ext2_superblock *sb = ext2_buffer_read(EXT2_SUPER, dev);
- if (sb->magic != EXT2_MAGIC) {
- free(sb);
+ struct ext2_superblock sb = { 0 };
+ ext2_get_superblock(&sb, dev);
+ if (sb.magic != EXT2_MAGIC)
return 0;
- }
struct vfs *vfs = zalloc(sizeof(*vfs));
vfs->type = VFS_EXT2;
@@ -507,6 +498,5 @@ CLEAR u8 ext2_load(struct vfs_dev *dev)
printf("Mounting disk %s to '/'\n", dev->name);
vfs_mount(dev, "/");
- free(sb);
return 1;
}