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-rw-r--r--mm/shmem.c96
1 files changed, 93 insertions, 3 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index 50c5b8f..5dd56f6 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -889,7 +889,7 @@ static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
if (!mpol || mpol->mode == MPOL_DEFAULT)
return; /* show nothing */
- mpol_to_str(buffer, sizeof(buffer), mpol, 1);
+ mpol_to_str(buffer, sizeof(buffer), mpol);
seq_printf(seq, ",mpol=%s", buffer);
}
@@ -1715,6 +1715,96 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
return error;
}
+/*
+ * llseek SEEK_DATA or SEEK_HOLE through the radix_tree.
+ */
+static pgoff_t shmem_seek_hole_data(struct address_space *mapping,
+ pgoff_t index, pgoff_t end, int whence)
+{
+ struct page *page;
+ struct pagevec pvec;
+ pgoff_t indices[PAGEVEC_SIZE];
+ bool done = false;
+ int i;
+
+ pagevec_init(&pvec, 0);
+ pvec.nr = 1; /* start small: we may be there already */
+ while (!done) {
+ pvec.nr = shmem_find_get_pages_and_swap(mapping, index,
+ pvec.nr, pvec.pages, indices);
+ if (!pvec.nr) {
+ if (whence == SEEK_DATA)
+ index = end;
+ break;
+ }
+ for (i = 0; i < pvec.nr; i++, index++) {
+ if (index < indices[i]) {
+ if (whence == SEEK_HOLE) {
+ done = true;
+ break;
+ }
+ index = indices[i];
+ }
+ page = pvec.pages[i];
+ if (page && !radix_tree_exceptional_entry(page)) {
+ if (!PageUptodate(page))
+ page = NULL;
+ }
+ if (index >= end ||
+ (page && whence == SEEK_DATA) ||
+ (!page && whence == SEEK_HOLE)) {
+ done = true;
+ break;
+ }
+ }
+ shmem_deswap_pagevec(&pvec);
+ pagevec_release(&pvec);
+ pvec.nr = PAGEVEC_SIZE;
+ cond_resched();
+ }
+ return index;
+}
+
+static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct address_space *mapping = file->f_mapping;
+ struct inode *inode = mapping->host;
+ pgoff_t start, end;
+ loff_t new_offset;
+
+ if (whence != SEEK_DATA && whence != SEEK_HOLE)
+ return generic_file_llseek_size(file, offset, whence,
+ MAX_LFS_FILESIZE, i_size_read(inode));
+ mutex_lock(&inode->i_mutex);
+ /* We're holding i_mutex so we can access i_size directly */
+
+ if (offset < 0)
+ offset = -EINVAL;
+ else if (offset >= inode->i_size)
+ offset = -ENXIO;
+ else {
+ start = offset >> PAGE_CACHE_SHIFT;
+ end = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ new_offset = shmem_seek_hole_data(mapping, start, end, whence);
+ new_offset <<= PAGE_CACHE_SHIFT;
+ if (new_offset > offset) {
+ if (new_offset < inode->i_size)
+ offset = new_offset;
+ else if (whence == SEEK_DATA)
+ offset = -ENXIO;
+ else
+ offset = inode->i_size;
+ }
+ }
+
+ if (offset >= 0 && offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+ mutex_unlock(&inode->i_mutex);
+ return offset;
+}
+
static long shmem_fallocate(struct file *file, int mode, loff_t offset,
loff_t len)
{
@@ -2373,7 +2463,7 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo,
if (!gid_valid(sbinfo->gid))
goto bad_val;
} else if (!strcmp(this_char,"mpol")) {
- if (mpol_parse_str(value, &sbinfo->mpol, 1))
+ if (mpol_parse_str(value, &sbinfo->mpol))
goto bad_val;
} else {
printk(KERN_ERR "tmpfs: Bad mount option %s\n",
@@ -2586,7 +2676,7 @@ static const struct address_space_operations shmem_aops = {
static const struct file_operations shmem_file_operations = {
.mmap = shmem_mmap,
#ifdef CONFIG_TMPFS
- .llseek = generic_file_llseek,
+ .llseek = shmem_file_llseek,
.read = do_sync_read,
.write = do_sync_write,
.aio_read = shmem_file_aio_read,
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