Currently, hugetlb_reserve_pages() returns a bool to indicate whether
the reservation map update for the range [from, to] was successful or
not. This is not sufficient for the case where the caller needs to
determine how many entries were updated for the range.
Therefore, have hugetlb_reserve_pages() return the number of entries
updated in the reservation map associated with the range [from, to].
Also, update the callers of hugetlb_reserve_pages() to handle the new
return value.
Cc: Steve Sistare <steven.sist...@oracle.com>
Cc: Muchun Song <muchun.s...@linux.dev>
Cc: David Hildenbrand <da...@redhat.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Signed-off-by: Vivek Kasireddy <vivek.kasire...@intel.com>
---
fs/hugetlbfs/inode.c | 8 ++++----
include/linux/hugetlb.h | 2 +-
mm/hugetlb.c | 19 +++++++++++++------
3 files changed, 18 insertions(+), 11 deletions(-)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index e4de5425838d..00b2d1a032fd 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -150,10 +150,10 @@ static int hugetlbfs_file_mmap(struct file *file, struct
vm_area_struct *vma)
if (inode->i_flags & S_PRIVATE)
vm_flags |= VM_NORESERVE;
- if (!hugetlb_reserve_pages(inode,
+ if (hugetlb_reserve_pages(inode,
vma->vm_pgoff >> huge_page_order(h),
len >> huge_page_shift(h), vma,
- vm_flags))
+ vm_flags) < 0)
goto out;
ret = 0;
@@ -1561,9 +1561,9 @@ struct file *hugetlb_file_setup(const char *name, size_t
size,
inode->i_size = size;
clear_nlink(inode);
- if (!hugetlb_reserve_pages(inode, 0,
+ if (hugetlb_reserve_pages(inode, 0,
size >> huge_page_shift(hstate_inode(inode)), NULL,
- acctflag))
+ acctflag) < 0)
file = ERR_PTR(-ENOMEM);
else
file = alloc_file_pseudo(inode, mnt, name, O_RDWR,
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8f3ac832ee7f..793d8390d3e4 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -148,7 +148,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
uffd_flags_t flags,
struct folio **foliop);
#endif /* CONFIG_USERFAULTFD */
-bool hugetlb_reserve_pages(struct inode *inode, long from, long to,
+long hugetlb_reserve_pages(struct inode *inode, long from, long to,
struct vm_area_struct *vma,
vm_flags_t vm_flags);
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7ae38bfb9096..cba9d60a4e28 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7241,8 +7241,15 @@ long hugetlb_change_protection(struct vm_area_struct
*vma,
return pages > 0 ? (pages << h->order) : pages;
}
-/* Return true if reservation was successful, false otherwise. */
-bool hugetlb_reserve_pages(struct inode *inode,
+/*
+ * Update the reservation map for the range [from, to].
+ *
+ * Returns the number of entries that would be added to the reservation map
+ * associated with the range [from, to]. This number is greater or equal to
+ * zero. -EINVAL or -ENOMEM is returned in case of any errors.
+ */
+
+long hugetlb_reserve_pages(struct inode *inode,
long from, long to,
struct vm_area_struct *vma,
vm_flags_t vm_flags)
@@ -7257,7 +7264,7 @@ bool hugetlb_reserve_pages(struct inode *inode,
/* This should never happen */
if (from > to) {
VM_WARN(1, "%s called with a negative range\n", __func__);
- return false;
+ return -EINVAL;
}
/*
@@ -7272,7 +7279,7 @@ bool hugetlb_reserve_pages(struct inode *inode,
* without using reserves
*/
if (vm_flags & VM_NORESERVE)
- return true;
+ return 0;
/*
* Shared mappings base their reservation on the number of pages that
@@ -7379,7 +7386,7 @@ bool hugetlb_reserve_pages(struct inode *inode,
hugetlb_cgroup_put_rsvd_cgroup(h_cg);
}
}
- return true;
+ return chg;
out_put_pages:
spool_resv = chg - gbl_reserve;
@@ -7407,7 +7414,7 @@ bool hugetlb_reserve_pages(struct inode *inode,
kref_put(&resv_map->refs, resv_map_release);
set_vma_resv_map(vma, NULL);
}
- return false;
+ return chg < 0 ? chg : add < 0 ? add : -EINVAL;
}
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
--
2.49.0
