Re: [U-Boot] [PATCH 1/4] fs: fat: write to non-cluster-aligned root directory

On 5/13/19 7:49 AM, AKASHI Takahiro wrote:

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

Thanks a lot for addressing this.

---

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);
  

This seems to be an unrelated change. It should be either in a separate patch or the commit message should explain why it is related.

Tested-by: Heinrich Schuchardt xypron.glpk@gmx.de

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");