With the commit below, fat now correctly handles a file read under a non-cluster-aligned root directory of fat12/16. Write operation should be fixed in the same manner.
Fixes: commit 9b18358dc05d ("fs: fat: fix reading non-cluster-aligned root directory") Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Anssi Hannula anssi.hannula@bitwise.fi --- fs/fat/fat.c | 15 ++++----- fs/fat/fat_write.c | 78 +++++++++++++++++++++++++++++++--------------- 2 files changed, 61 insertions(+), 32 deletions(-)
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index c5997c21735f..fccaa385d187 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -619,13 +619,14 @@ static int get_fs_info(fsdata *mydata) return -1; }
- debug("FAT%d, fat_sect: %d, fatlength: %d\n", - mydata->fatsize, mydata->fat_sect, mydata->fatlength); - debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n" - "Data begins at: %d\n", - mydata->root_cluster, - mydata->rootdir_sect, - mydata->rootdir_sect * mydata->sect_size, mydata->data_begin); + debug("FAT%d, fat_sect: %d, fatlength: %d, num: %d\n", + mydata->fatsize, mydata->fat_sect, mydata->fatlength, + mydata->fats); + debug("Rootdir begins at cluster: %d, sector: %d, size: %x\n" + "Data begins at: %d\n", + mydata->root_cluster, + mydata->rootdir_sect, + mydata->rootdir_size * mydata->sect_size, mydata->data_begin); debug("Sector size: %d, cluster size: %d\n", mydata->sect_size, mydata->clust_size);
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 852f874e5817..3bc0dd637521 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -388,29 +388,23 @@ static __u32 determine_fatent(fsdata *mydata, __u32 entry) }
/** - * set_cluster() - write data to cluster + * set_sectors() - write data to sectors * - * Write 'size' bytes from 'buffer' into the specified cluster. + * Write 'size' bytes from 'buffer' into the specified sector. * * @mydata: data to be written - * @clustnum: cluster to be written to + * @startsect: sector to be written to * @buffer: data to be written * @size: bytes to be written (but not more than the size of a cluster) * Return: 0 on success, -1 otherwise */ static int -set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size) +set_sectors(fsdata *mydata, u32 startsect, u8 *buffer, u32 size) { - u32 idx = 0; - u32 startsect; + u32 nsects = 0; int ret;
- if (clustnum > 0) - startsect = clust_to_sect(mydata, clustnum); - else - startsect = mydata->rootdir_sect; - - debug("clustnum: %d, startsect: %d\n", clustnum, startsect); + debug("startsect: %d\n", startsect);
if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) { ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); @@ -429,17 +423,16 @@ set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size) size -= mydata->sect_size; } } else if (size >= mydata->sect_size) { - idx = size / mydata->sect_size; - ret = disk_write(startsect, idx, buffer); - if (ret != idx) { + nsects = size / mydata->sect_size; + ret = disk_write(startsect, nsects, buffer); + if (ret != nsects) { debug("Error writing data (got %d)\n", ret); return -1; }
- startsect += idx; - idx *= mydata->sect_size; - buffer += idx; - size -= idx; + startsect += nsects; + buffer += nsects * mydata->sect_size; + size -= nsects * mydata->sect_size; }
if (size) { @@ -457,6 +450,44 @@ set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size) return 0; }
+/** + * set_cluster() - write data to cluster + * + * Write 'size' bytes from 'buffer' into the specified cluster. + * + * @mydata: data to be written + * @clustnum: cluster to be written to + * @buffer: data to be written + * @size: bytes to be written (but not more than the size of a cluster) + * Return: 0 on success, -1 otherwise + */ +static int +set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size) +{ + return set_sectors(mydata, clust_to_sect(mydata, clustnum), + buffer, size); +} + +static int +flush_dir(fat_itr *itr) +{ + fsdata *mydata = itr->fsdata; + u32 startsect, sect_offset, nsects; + + if (!itr->is_root || mydata->fatsize == 32) + return set_cluster(mydata, itr->clust, itr->block, + mydata->clust_size * mydata->sect_size); + + sect_offset = itr->clust * mydata->clust_size; + startsect = mydata->rootdir_sect + sect_offset; + /* do not write past the end of rootdir */ + nsects = min_t(u32, mydata->clust_size, + mydata->rootdir_size - sect_offset); + + return set_sectors(mydata, startsect, itr->block, + nsects * mydata->sect_size); +} + static __u8 tmpbuf_cluster[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN);
/* @@ -1171,8 +1202,7 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer, }
/* Write directory table to device */ - ret = set_cluster(mydata, itr->clust, itr->block, - mydata->clust_size * mydata->sect_size); + ret = flush_dir(itr); if (ret) { printf("Error: writing directory entry\n"); ret = -EIO; @@ -1249,8 +1279,7 @@ static int delete_dentry(fat_itr *itr) memset(dentptr, 0, sizeof(*dentptr)); dentptr->name[0] = 0xe5;
- if (set_cluster(mydata, itr->clust, itr->block, - mydata->clust_size * mydata->sect_size) != 0) { + if (flush_dir(itr)) { printf("error: writing directory entry\n"); return -EIO; } @@ -1452,8 +1481,7 @@ int fat_mkdir(const char *new_dirname) }
/* Write directory table to device */ - ret = set_cluster(mydata, itr->clust, itr->block, - mydata->clust_size * mydata->sect_size); + ret = flush_dir(itr); if (ret) printf("Error: writing directory entry\n");