[PATCH v3 1/3] erofs-utils: lib: export parts of erofs_pread()
Yue Hu
zbestahu at gmail.com
Tue Jan 10 20:28:19 AEDT 2023
From: Yue Hu <huyue2 at coolpad.com>
Export parts of erofs_pread() to avoid duplicated code in
erofs_verify_inode_data(). Let's make two helpers for this.
Signed-off-by: Yue Hu <huyue2 at coolpad.com>
---
v3: rename the helpers as {z_}erofs_read_one_data
v2: use parameter trimmed instead of partial
include/erofs/internal.h | 5 ++
lib/data.c | 153 ++++++++++++++++++++++-----------------
2 files changed, 91 insertions(+), 67 deletions(-)
diff --git a/include/erofs/internal.h b/include/erofs/internal.h
index 206913c..08a3877 100644
--- a/include/erofs/internal.h
+++ b/include/erofs/internal.h
@@ -355,6 +355,11 @@ int erofs_pread(struct erofs_inode *inode, char *buf,
int erofs_map_blocks(struct erofs_inode *inode,
struct erofs_map_blocks *map, int flags);
int erofs_map_dev(struct erofs_sb_info *sbi, struct erofs_map_dev *map);
+int erofs_read_one_data(struct erofs_map_blocks *map, char *buffer, u64 offset,
+ size_t len);
+int z_erofs_read_one_data(struct erofs_inode *inode,
+ struct erofs_map_blocks *map, char *raw, char *buffer,
+ erofs_off_t skip, erofs_off_t length, bool trimmed);
static inline int erofs_get_occupied_size(const struct erofs_inode *inode,
erofs_off_t *size)
diff --git a/lib/data.c b/lib/data.c
index 76a6677..c7d08e7 100644
--- a/lib/data.c
+++ b/lib/data.c
@@ -158,19 +158,38 @@ int erofs_map_dev(struct erofs_sb_info *sbi, struct erofs_map_dev *map)
return 0;
}
+int erofs_read_one_data(struct erofs_map_blocks *map, char *buffer, u64 offset,
+ size_t len)
+{
+ struct erofs_map_dev mdev;
+ int ret;
+
+ mdev = (struct erofs_map_dev) {
+ .m_deviceid = map->m_deviceid,
+ .m_pa = map->m_pa,
+ };
+ ret = erofs_map_dev(&sbi, &mdev);
+ if (ret)
+ return ret;
+
+ ret = dev_read(mdev.m_deviceid, buffer, mdev.m_pa + offset, len);
+ if (ret < 0)
+ return -EIO;
+ return 0;
+}
+
static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
erofs_off_t size, erofs_off_t offset)
{
struct erofs_map_blocks map = {
.index = UINT_MAX,
};
- struct erofs_map_dev mdev;
int ret;
erofs_off_t ptr = offset;
while (ptr < offset + size) {
char *const estart = buffer + ptr - offset;
- erofs_off_t eend;
+ erofs_off_t eend, moff = 0;
map.m_la = ptr;
ret = erofs_map_blocks(inode, &map, 0);
@@ -179,14 +198,6 @@ static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
DBG_BUGON(map.m_plen != map.m_llen);
- mdev = (struct erofs_map_dev) {
- .m_deviceid = map.m_deviceid,
- .m_pa = map.m_pa,
- };
- ret = erofs_map_dev(&sbi, &mdev);
- if (ret)
- return ret;
-
/* trim extent */
eend = min(offset + size, map.m_la + map.m_llen);
DBG_BUGON(ptr < map.m_la);
@@ -204,19 +215,73 @@ static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
}
if (ptr > map.m_la) {
- mdev.m_pa += ptr - map.m_la;
+ moff = ptr - map.m_la;
map.m_la = ptr;
}
- ret = dev_read(mdev.m_deviceid, estart, mdev.m_pa,
- eend - map.m_la);
- if (ret < 0)
- return -EIO;
+ ret = erofs_read_one_data(&map, estart, moff, eend - map.m_la);
+ if (ret)
+ return ret;
ptr = eend;
}
return 0;
}
+int z_erofs_read_one_data(struct erofs_inode *inode,
+ struct erofs_map_blocks *map, char *raw, char *buffer,
+ erofs_off_t skip, erofs_off_t length, bool trimmed)
+{
+ struct erofs_map_dev mdev;
+ int ret = 0;
+
+ if (map->m_flags & EROFS_MAP_FRAGMENT) {
+ struct erofs_inode packed_inode = {
+ .nid = sbi.packed_nid,
+ };
+
+ ret = erofs_read_inode_from_disk(&packed_inode);
+ if (ret) {
+ erofs_err("failed to read packed inode from disk");
+ return ret;
+ }
+
+ return erofs_pread(&packed_inode, buffer, length - skip,
+ inode->fragmentoff + skip);
+ }
+
+ /* no device id here, thus it will always succeed */
+ mdev = (struct erofs_map_dev) {
+ .m_pa = map->m_pa,
+ };
+ ret = erofs_map_dev(&sbi, &mdev);
+ if (ret) {
+ DBG_BUGON(1);
+ return ret;
+ }
+
+ ret = dev_read(mdev.m_deviceid, raw, mdev.m_pa, map->m_plen);
+ if (ret < 0)
+ return ret;
+
+ ret = z_erofs_decompress(&(struct z_erofs_decompress_req) {
+ .in = raw,
+ .out = buffer,
+ .decodedskip = skip,
+ .interlaced_offset =
+ map->m_algorithmformat == Z_EROFS_COMPRESSION_INTERLACED ?
+ erofs_blkoff(map->m_la) : 0,
+ .inputsize = map->m_plen,
+ .decodedlength = length,
+ .alg = map->m_algorithmformat,
+ .partial_decoding = trimmed ? true :
+ !(map->m_flags & EROFS_MAP_FULL_MAPPED) ||
+ (map->m_flags & EROFS_MAP_PARTIAL_REF),
+ });
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
erofs_off_t size, erofs_off_t offset)
{
@@ -224,9 +289,8 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
struct erofs_map_blocks map = {
.index = UINT_MAX,
};
- struct erofs_map_dev mdev;
- bool partial;
- unsigned int bufsize = 0, interlaced_offset;
+ bool trimmed;
+ unsigned int bufsize = 0;
char *raw = NULL;
int ret = 0;
@@ -238,28 +302,17 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
if (ret)
break;
- /* no device id here, thus it will always succeed */
- mdev = (struct erofs_map_dev) {
- .m_pa = map.m_pa,
- };
- ret = erofs_map_dev(&sbi, &mdev);
- if (ret) {
- DBG_BUGON(1);
- break;
- }
-
/*
* trim to the needed size if the returned extent is quite
* larger than requested, and set up partial flag as well.
*/
if (end < map.m_la + map.m_llen) {
length = end - map.m_la;
- partial = true;
+ trimmed = true;
} else {
DBG_BUGON(end != map.m_la + map.m_llen);
length = map.m_llen;
- partial = !(map.m_flags & EROFS_MAP_FULL_MAPPED) ||
- (map.m_flags & EROFS_MAP_PARTIAL_REF);
+ trimmed = false;
}
if (map.m_la < offset) {
@@ -276,25 +329,6 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
continue;
}
- if (map.m_flags & EROFS_MAP_FRAGMENT) {
- struct erofs_inode packed_inode = {
- .nid = sbi.packed_nid,
- };
-
- ret = erofs_read_inode_from_disk(&packed_inode);
- if (ret) {
- erofs_err("failed to read packed inode from disk");
- return ret;
- }
-
- ret = z_erofs_read_data(&packed_inode,
- buffer + end - offset, length - skip,
- inode->fragmentoff + skip);
- if (ret < 0)
- break;
- continue;
- }
-
if (map.m_plen > bufsize) {
bufsize = map.m_plen;
raw = realloc(raw, bufsize);
@@ -303,24 +337,9 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
break;
}
}
- ret = dev_read(mdev.m_deviceid, raw, mdev.m_pa, map.m_plen);
- if (ret < 0)
- break;
- interlaced_offset = 0;
- if (map.m_algorithmformat == Z_EROFS_COMPRESSION_INTERLACED)
- interlaced_offset = erofs_blkoff(map.m_la);
-
- ret = z_erofs_decompress(&(struct z_erofs_decompress_req) {
- .in = raw,
- .out = buffer + end - offset,
- .decodedskip = skip,
- .interlaced_offset = interlaced_offset,
- .inputsize = map.m_plen,
- .decodedlength = length,
- .alg = map.m_algorithmformat,
- .partial_decoding = partial
- });
+ ret = z_erofs_read_one_data(inode, &map, raw,
+ buffer + end - offset, skip, length, trimmed);
if (ret < 0)
break;
}
--
2.17.1
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