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-rw-r--r--fs/fat/cache.c79
-rw-r--r--fs/fat/dir.c2
-rw-r--r--fs/fat/fat.h8
-rw-r--r--fs/fat/fatent.c24
-rw-r--r--fs/fat/file.c61
-rw-r--r--fs/fat/inode.c106
6 files changed, 231 insertions, 49 deletions
diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index 93fc62232ec2..5d384921524d 100644
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -301,15 +301,59 @@ static int fat_bmap_cluster(struct inode *inode, int cluster)
return dclus;
}
-int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
- unsigned long *mapped_blocks, int create)
+int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
+ sector_t last_block,
+ unsigned long *mapped_blocks, sector_t *bmap)
{
struct super_block *sb = inode->i_sb;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ int cluster, offset;
+
+ cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
+ offset = sector & (sbi->sec_per_clus - 1);
+ cluster = fat_bmap_cluster(inode, cluster);
+ if (cluster < 0)
+ return cluster;
+ else if (cluster) {
+ *bmap = fat_clus_to_blknr(sbi, cluster) + offset;
+ *mapped_blocks = sbi->sec_per_clus - offset;
+ if (*mapped_blocks > last_block - sector)
+ *mapped_blocks = last_block - sector;
+ }
+
+ return 0;
+}
+
+static int is_exceed_eof(struct inode *inode, sector_t sector,
+ sector_t *last_block, int create)
+{
+ struct super_block *sb = inode->i_sb;
const unsigned long blocksize = sb->s_blocksize;
const unsigned char blocksize_bits = sb->s_blocksize_bits;
+
+ *last_block = (i_size_read(inode) + (blocksize - 1)) >> blocksize_bits;
+ if (sector >= *last_block) {
+ if (!create)
+ return 1;
+
+ /*
+ * ->mmu_private can access on only allocation path.
+ * (caller must hold ->i_mutex)
+ */
+ *last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1))
+ >> blocksize_bits;
+ if (sector >= *last_block)
+ return 1;
+ }
+
+ return 0;
+}
+
+int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
+ unsigned long *mapped_blocks, int create, bool from_bmap)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
sector_t last_block;
- int cluster, offset;
*phys = 0;
*mapped_blocks = 0;
@@ -321,31 +365,16 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
return 0;
}
- last_block = (i_size_read(inode) + (blocksize - 1)) >> blocksize_bits;
- if (sector >= last_block) {
- if (!create)
+ if (!from_bmap) {
+ if (is_exceed_eof(inode, sector, &last_block, create))
return 0;
-
- /*
- * ->mmu_private can access on only allocation path.
- * (caller must hold ->i_mutex)
- */
- last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1))
- >> blocksize_bits;
+ } else {
+ last_block = inode->i_blocks >>
+ (inode->i_sb->s_blocksize_bits - 9);
if (sector >= last_block)
return 0;
}
- cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
- offset = sector & (sbi->sec_per_clus - 1);
- cluster = fat_bmap_cluster(inode, cluster);
- if (cluster < 0)
- return cluster;
- else if (cluster) {
- *phys = fat_clus_to_blknr(sbi, cluster) + offset;
- *mapped_blocks = sbi->sec_per_clus - offset;
- if (*mapped_blocks > last_block - sector)
- *mapped_blocks = last_block - sector;
- }
- return 0;
+ return fat_get_mapped_cluster(inode, sector, last_block, mapped_blocks,
+ phys);
}
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 8b2127ffb226..7def96caec5f 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -91,7 +91,7 @@ next:
*bh = NULL;
iblock = *pos >> sb->s_blocksize_bits;
- err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0);
+ err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false);
if (err || !phys)
return -1; /* beyond EOF or error */
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index be5e15323bab..e6b764a17a9c 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -87,7 +87,7 @@ struct msdos_sb_info {
unsigned int vol_id; /*volume ID*/
int fatent_shift;
- struct fatent_operations *fatent_ops;
+ const struct fatent_operations *fatent_ops;
struct inode *fat_inode;
struct inode *fsinfo_inode;
@@ -285,8 +285,11 @@ static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
extern void fat_cache_inval_inode(struct inode *inode);
extern int fat_get_cluster(struct inode *inode, int cluster,
int *fclus, int *dclus);
+extern int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
+ sector_t last_block,
+ unsigned long *mapped_blocks, sector_t *bmap);
extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
- unsigned long *mapped_blocks, int create);
+ unsigned long *mapped_blocks, int create, bool from_bmap);
/* fat/dir.c */
extern const struct file_operations fat_dir_operations;
@@ -384,6 +387,7 @@ static inline unsigned long fat_dir_hash(int logstart)
{
return hash_32(logstart, FAT_HASH_BITS);
}
+extern int fat_add_cluster(struct inode *inode);
/* fat/misc.c */
extern __printf(3, 4) __cold
diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c
index 8226557130a2..1d9a8c4e9de0 100644
--- a/fs/fat/fatent.c
+++ b/fs/fat/fatent.c
@@ -99,7 +99,7 @@ err:
static int fat_ent_bread(struct super_block *sb, struct fat_entry *fatent,
int offset, sector_t blocknr)
{
- struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
+ const struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
WARN_ON(blocknr < MSDOS_SB(sb)->fat_start);
fatent->fat_inode = MSDOS_SB(sb)->fat_inode;
@@ -246,7 +246,7 @@ static int fat32_ent_next(struct fat_entry *fatent)
return 0;
}
-static struct fatent_operations fat12_ops = {
+static const struct fatent_operations fat12_ops = {
.ent_blocknr = fat12_ent_blocknr,
.ent_set_ptr = fat12_ent_set_ptr,
.ent_bread = fat12_ent_bread,
@@ -255,7 +255,7 @@ static struct fatent_operations fat12_ops = {
.ent_next = fat12_ent_next,
};
-static struct fatent_operations fat16_ops = {
+static const struct fatent_operations fat16_ops = {
.ent_blocknr = fat_ent_blocknr,
.ent_set_ptr = fat16_ent_set_ptr,
.ent_bread = fat_ent_bread,
@@ -264,7 +264,7 @@ static struct fatent_operations fat16_ops = {
.ent_next = fat16_ent_next,
};
-static struct fatent_operations fat32_ops = {
+static const struct fatent_operations fat32_ops = {
.ent_blocknr = fat_ent_blocknr,
.ent_set_ptr = fat32_ent_set_ptr,
.ent_bread = fat_ent_bread,
@@ -320,7 +320,7 @@ static inline int fat_ent_update_ptr(struct super_block *sb,
int offset, sector_t blocknr)
{
struct msdos_sb_info *sbi = MSDOS_SB(sb);
- struct fatent_operations *ops = sbi->fatent_ops;
+ const struct fatent_operations *ops = sbi->fatent_ops;
struct buffer_head **bhs = fatent->bhs;
/* Is this fatent's blocks including this entry? */
@@ -349,7 +349,7 @@ int fat_ent_read(struct inode *inode, struct fat_entry *fatent, int entry)
{
struct super_block *sb = inode->i_sb;
struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
- struct fatent_operations *ops = sbi->fatent_ops;
+ const struct fatent_operations *ops = sbi->fatent_ops;
int err, offset;
sector_t blocknr;
@@ -407,7 +407,7 @@ int fat_ent_write(struct inode *inode, struct fat_entry *fatent,
int new, int wait)
{
struct super_block *sb = inode->i_sb;
- struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
+ const struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
int err;
ops->ent_put(fatent, new);
@@ -432,7 +432,7 @@ static inline int fat_ent_next(struct msdos_sb_info *sbi,
static inline int fat_ent_read_block(struct super_block *sb,
struct fat_entry *fatent)
{
- struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
+ const struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
sector_t blocknr;
int offset;
@@ -463,7 +463,7 @@ int fat_alloc_clusters(struct inode *inode, int *cluster, int nr_cluster)
{
struct super_block *sb = inode->i_sb;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
- struct fatent_operations *ops = sbi->fatent_ops;
+ const struct fatent_operations *ops = sbi->fatent_ops;
struct fat_entry fatent, prev_ent;
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
int i, count, err, nr_bhs, idx_clus;
@@ -551,7 +551,7 @@ int fat_free_clusters(struct inode *inode, int cluster)
{
struct super_block *sb = inode->i_sb;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
- struct fatent_operations *ops = sbi->fatent_ops;
+ const struct fatent_operations *ops = sbi->fatent_ops;
struct fat_entry fatent;
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
int i, err, nr_bhs;
@@ -636,7 +636,7 @@ EXPORT_SYMBOL_GPL(fat_free_clusters);
static void fat_ent_reada(struct super_block *sb, struct fat_entry *fatent,
unsigned long reada_blocks)
{
- struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
+ const struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;
sector_t blocknr;
int i, offset;
@@ -649,7 +649,7 @@ static void fat_ent_reada(struct super_block *sb, struct fat_entry *fatent,
int fat_count_free_clusters(struct super_block *sb)
{
struct msdos_sb_info *sbi = MSDOS_SB(sb);
- struct fatent_operations *ops = sbi->fatent_ops;
+ const struct fatent_operations *ops = sbi->fatent_ops;
struct fat_entry fatent;
unsigned long reada_blocks, reada_mask, cur_block;
int err = 0, free;
diff --git a/fs/fat/file.c b/fs/fat/file.c
index a08f1039909a..43d3475da83a 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -14,8 +14,12 @@
#include <linux/backing-dev.h>
#include <linux/fsnotify.h>
#include <linux/security.h>
+#include <linux/falloc.h>
#include "fat.h"
+static long fat_fallocate(struct file *file, int mode,
+ loff_t offset, loff_t len);
+
static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
{
u32 attr;
@@ -177,6 +181,7 @@ const struct file_operations fat_file_operations = {
#endif
.fsync = fat_file_fsync,
.splice_read = generic_file_splice_read,
+ .fallocate = fat_fallocate,
};
static int fat_cont_expand(struct inode *inode, loff_t size)
@@ -215,6 +220,62 @@ out:
return err;
}
+/*
+ * Preallocate space for a file. This implements fat's fallocate file
+ * operation, which gets called from sys_fallocate system call. User
+ * space requests len bytes at offset. If FALLOC_FL_KEEP_SIZE is set
+ * we just allocate clusters without zeroing them out. Otherwise we
+ * allocate and zero out clusters via an expanding truncate.
+ */
+static long fat_fallocate(struct file *file, int mode,
+ loff_t offset, loff_t len)
+{
+ int nr_cluster; /* Number of clusters to be allocated */
+ loff_t mm_bytes; /* Number of bytes to be allocated for file */
+ loff_t ondisksize; /* block aligned on-disk size in bytes*/
+ struct inode *inode = file->f_mapping->host;
+ struct super_block *sb = inode->i_sb;
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ int err = 0;
+
+ /* No support for hole punch or other fallocate flags. */
+ if (mode & ~FALLOC_FL_KEEP_SIZE)
+ return -EOPNOTSUPP;
+
+ /* No support for dir */
+ if (!S_ISREG(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ mutex_lock(&inode->i_mutex);
+ if (mode & FALLOC_FL_KEEP_SIZE) {
+ ondisksize = inode->i_blocks << 9;
+ if ((offset + len) <= ondisksize)
+ goto error;
+
+ /* First compute the number of clusters to be allocated */
+ mm_bytes = offset + len - ondisksize;
+ nr_cluster = (mm_bytes + (sbi->cluster_size - 1)) >>
+ sbi->cluster_bits;
+
+ /* Start the allocation.We are not zeroing out the clusters */
+ while (nr_cluster-- > 0) {
+ err = fat_add_cluster(inode);
+ if (err)
+ goto error;
+ }
+ } else {
+ if ((offset + len) <= i_size_read(inode))
+ goto error;
+
+ /* This is just an expanding truncate */
+ err = fat_cont_expand(inode, (offset + len));
+ }
+
+error:
+ mutex_unlock(&inode->i_mutex);
+ return err;
+}
+
/* Free all clusters after the skip'th cluster. */
static int fat_free(struct inode *inode, int skip)
{
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 509411dd3698..a5599052116c 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -93,7 +93,7 @@ static struct fat_floppy_defaults {
},
};
-static int fat_add_cluster(struct inode *inode)
+int fat_add_cluster(struct inode *inode)
{
int err, cluster;
@@ -115,10 +115,10 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock,
struct super_block *sb = inode->i_sb;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
unsigned long mapped_blocks;
- sector_t phys;
+ sector_t phys, last_block;
int err, offset;
- err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
+ err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create, false);
if (err)
return err;
if (phys) {
@@ -135,8 +135,14 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock,
return -EIO;
}
+ last_block = inode->i_blocks >> (sb->s_blocksize_bits - 9);
offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
- if (!offset) {
+ /*
+ * allocate a cluster according to the following.
+ * 1) no more available blocks
+ * 2) not part of fallocate region
+ */
+ if (!offset && !(iblock < last_block)) {
/* TODO: multiple cluster allocation would be desirable. */
err = fat_add_cluster(inode);
if (err)
@@ -148,7 +154,7 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock,
*max_blocks = min(mapped_blocks, *max_blocks);
MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
- err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
+ err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create, false);
if (err)
return err;
@@ -273,13 +279,38 @@ static ssize_t fat_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
return ret;
}
+static int fat_get_block_bmap(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ struct super_block *sb = inode->i_sb;
+ unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
+ int err;
+ sector_t bmap;
+ unsigned long mapped_blocks;
+
+ BUG_ON(create != 0);
+
+ err = fat_bmap(inode, iblock, &bmap, &mapped_blocks, create, true);
+ if (err)
+ return err;
+
+ if (bmap) {
+ map_bh(bh_result, sb, bmap);
+ max_blocks = min(mapped_blocks, max_blocks);
+ }
+
+ bh_result->b_size = max_blocks << sb->s_blocksize_bits;
+
+ return 0;
+}
+
static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
{
sector_t blocknr;
/* fat_get_cluster() assumes the requested blocknr isn't truncated. */
down_read(&MSDOS_I(mapping->host)->truncate_lock);
- blocknr = generic_block_bmap(mapping, block, fat_get_block);
+ blocknr = generic_block_bmap(mapping, block, fat_get_block_bmap);
up_read(&MSDOS_I(mapping->host)->truncate_lock);
return blocknr;
@@ -449,6 +480,24 @@ static int fat_calc_dir_size(struct inode *inode)
return 0;
}
+static int fat_validate_dir(struct inode *dir)
+{
+ struct super_block *sb = dir->i_sb;
+
+ if (dir->i_nlink < 2) {
+ /* Directory should have "."/".." entries at least. */
+ fat_fs_error(sb, "corrupted directory (invalid entries)");
+ return -EIO;
+ }
+ if (MSDOS_I(dir)->i_start == 0 ||
+ MSDOS_I(dir)->i_start == MSDOS_SB(sb)->root_cluster) {
+ /* Directory should point valid cluster. */
+ fat_fs_error(sb, "corrupted directory (invalid i_start)");
+ return -EIO;
+ }
+ return 0;
+}
+
/* doesn't deal with root inode */
int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
{
@@ -475,6 +524,10 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
MSDOS_I(inode)->mmu_private = inode->i_size;
set_nlink(inode, fat_subdirs(inode));
+
+ error = fat_validate_dir(inode);
+ if (error < 0)
+ return error;
} else { /* not a directory */
inode->i_generation |= 1;
inode->i_mode = fat_make_mode(sbi, de->attr,
@@ -553,13 +606,43 @@ out:
EXPORT_SYMBOL_GPL(fat_build_inode);
+static int __fat_write_inode(struct inode *inode, int wait);
+
+static void fat_free_eofblocks(struct inode *inode)
+{
+ /* Release unwritten fallocated blocks on inode eviction. */
+ if ((inode->i_blocks << 9) >
+ round_up(MSDOS_I(inode)->mmu_private,
+ MSDOS_SB(inode->i_sb)->cluster_size)) {
+ int err;
+
+ fat_truncate_blocks(inode, MSDOS_I(inode)->mmu_private);
+ /* Fallocate results in updating the i_start/iogstart
+ * for the zero byte file. So, make it return to
+ * original state during evict and commit it to avoid
+ * any corruption on the next access to the cluster
+ * chain for the file.
+ */
+ err = __fat_write_inode(inode, inode_needs_sync(inode));
+ if (err) {
+ fat_msg(inode->i_sb, KERN_WARNING, "Failed to "
+ "update on disk inode for unused "
+ "fallocated blocks, inode could be "
+ "corrupted. Please run fsck");
+ }
+
+ }
+}
+
static void fat_evict_inode(struct inode *inode)
{
truncate_inode_pages_final(&inode->i_data);
if (!inode->i_nlink) {
inode->i_size = 0;
fat_truncate_blocks(inode, 0);
- }
+ } else
+ fat_free_eofblocks(inode);
+
invalidate_inode_buffers(inode);
clear_inode(inode);
fat_cache_inval_inode(inode);
@@ -677,7 +760,7 @@ static int __init fat_init_inodecache(void)
fat_inode_cachep = kmem_cache_create("fat_inode_cache",
sizeof(struct msdos_inode_info),
0, (SLAB_RECLAIM_ACCOUNT|
- SLAB_MEM_SPREAD),
+ SLAB_MEM_SPREAD|SLAB_ACCOUNT),
init_once);
if (fat_inode_cachep == NULL)
return -ENOMEM;
@@ -1146,7 +1229,12 @@ static int parse_options(struct super_block *sb, char *options, int is_vfat,
case Opt_time_offset:
if (match_int(&args[0], &option))
return -EINVAL;
- if (option < -12 * 60 || option > 12 * 60)
+ /*
+ * GMT+-12 zones may have DST corrections so at least
+ * 13 hours difference is needed. Make the limit 24
+ * just in case someone invents something unusual.
+ */
+ if (option < -24 * 60 || option > 24 * 60)
return -EINVAL;
opts->tz_set = 1;
opts->time_offset = option;
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-27 22:07:35 +0300