From: Christopher Hoffman <choffman@redhat.com>
Date: Mon, 20 Oct 2025 18:15:11 +0000 (+0000)
Subject: client: Use nearest fscrypt block when clamping max io size
X-Git-Tag: testing/wip-vshankar-testing-20260120.085915-debug^2~13^2~5
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=ae65b1b3e35c75608348a55b2bfa9d57c691d964;p=ceph-ci.git

client: Use nearest fscrypt block when clamping max io size

A max io size can currently be up to INT_MAX. If it is greater,
then clamp the size to INT_MAX. This conflicts with fscrypt io
operations. An fscrypt, op needs to read a whole fscrypt block.
The size of fscrypt block size is 4K, INT_MAX % 4K is not equal
to 0. Therefore, get the nearest multiple of 4K to INT_MAX that
does not go over. In the fscrypt case, this value will be used
for clamping max io size.

Fixes: https://tracker.ceph.com/issues/73346
Signed-off-by: Christopher Hoffman <choffman@redhat.com>
---

diff --git a/src/client/Client.cc b/src/client/Client.cc
index de3626862a4..d865dd7c4f6 100644
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -11315,8 +11315,18 @@ int Client::read(int fd, char *buf, loff_t size, loff_t offset)
     return -EBADF;
 #endif
   bufferlist bl;
-  /* We can't return bytes written larger than INT_MAX, clamp size to that */
+#if defined(__linux__)
+  /* We can't return bytes written larger than INT_MAX, clamp size to
+   * that or FSCRYPT_MAXIO_SIZE*/
+  Inode *in = f->inode.get();
+  if (in->is_fscrypt_enabled()) {
+    size = std::min(size, (loff_t)FSCRYPT_MAXIO_SIZE);
+  } else {
+    size = std::min(size, (loff_t)INT_MAX);
+  }
+#else
   size = std::min(size, (loff_t)INT_MAX);
+#endif
   int r = _read(f, offset, size, &bl);
   ldout(cct, 3) << "read(" << fd << ", " << (void*)buf << ", " << size << ", " << offset << ") = " << r << dendl;
   if (r >= 0) {
@@ -12017,8 +12027,18 @@ int Client::write(int fd, const char *buf, loff_t size, loff_t offset)
   if (fh->flags & O_PATH)
     return -EBADF;
 #endif
-  /* We can't return bytes written larger than INT_MAX, clamp size to that */
+#if defined(__linux__)
+  /* We can't return bytes written larger than INT_MAX, clamp size to
+   * that or FSCRYPT_MAXIO_SIZE*/
+  Inode *in = fh->inode.get();
+  if (in->is_fscrypt_enabled()) {
+    size = std::min(size, (loff_t)FSCRYPT_MAXIO_SIZE);
+  } else {
+    size = std::min(size, (loff_t)INT_MAX);
+  }
+#else
   size = std::min(size, (loff_t)INT_MAX);
+#endif
   bufferlist bl;
   bl.append(buf, size);
   int r = _write(fh, offset, size, std::move(bl));
@@ -12058,7 +12078,18 @@ int64_t Client::_preadv_pwritev_locked(Fh *fh, const struct iovec *iov,
      */
     bufferlist data;
     if (clamp_to_int) {
+#if defined(__linux__)
+  /* We can't return bytes written larger than INT_MAX, clamp size to
+   * that or FSCRYPT_MAXIO_SIZE*/
+      Inode *in = fh->inode.get();
+      if (in->is_fscrypt_enabled()) {
+        totallen = std::min(totallen, (size_t)FSCRYPT_MAXIO_SIZE);
+      } else {
+        totallen = std::min(totallen, (size_t)INT_MAX);
+      }
+#else
       totallen = std::min(totallen, (size_t)INT_MAX);
+#endif
       size_t total_appended = 0;
       for (int i = 0; i < iovcnt; i++) {
         if (iov[i].iov_len > 0) {
@@ -16979,9 +17010,19 @@ int Client::ll_read(Fh *fh, loff_t off, loff_t len, bufferlist *bl)
     return -ENOTCONN;
   }
 
+#if defined(__linux__)
+  /* We can't return bytes written larger than INT_MAX, clamp size to
+   * that or FSCRYPT_MAXIO_SIZE*/
+  Inode *in = fh->inode.get();
+  if (in->is_fscrypt_enabled()) {
+    len = std::min(len, (loff_t)FSCRYPT_MAXIO_SIZE);
+  } else {
   /* We can't return bytes written larger than INT_MAX, clamp len to that */
+    len = std::min(len, (loff_t)INT_MAX);
+  }
+#else
   len = std::min(len, (loff_t)INT_MAX);
-
+#endif
   std::scoped_lock lock(client_lock);
   if (fh == NULL || !_ll_fh_exists(fh)) {
     ldout(cct, 3) << "(fh)" << fh << " is invalid" << dendl;
@@ -17124,9 +17165,18 @@ int Client::ll_write(Fh *fh, loff_t off, loff_t len, const char *data)
     return -ENOTCONN;
   }
 
-  /* We can't return bytes written larger than INT_MAX, clamp len to that */
+#if defined(__linux__)
+  /* We can't return bytes written larger than INT_MAX, clamp size to
+   * that or FSCRYPT_MAXIO_SIZE*/
+  Inode *in = fh->inode.get();
+  if (in->is_fscrypt_enabled()) {
+    len = std::min(len, (loff_t)FSCRYPT_MAXIO_SIZE);
+  } else {
+    len = std::min(len, (loff_t)INT_MAX);
+  }
+#else
   len = std::min(len, (loff_t)INT_MAX);
-
+#endif
   std::scoped_lock lock(client_lock);
   if (fh == NULL || !_ll_fh_exists(fh)) {
     ldout(cct, 3) << "(fh)" << fh << " is invalid" << dendl;
diff --git a/src/client/FSCrypt.h b/src/client/FSCrypt.h
index 30b5a0300a3..97baee7fdb5 100644
--- a/src/client/FSCrypt.h
+++ b/src/client/FSCrypt.h
@@ -21,6 +21,10 @@
 
 #define FSCRYPT_DATA_ALIGNMENT 16
 
+// fscrypt maxio_size cannot be INT_MAX as it is not a multiple of fscrypt
+// block size. Set it to nearest fscrypt block without exceeding INT_MAX
+#define FSCRYPT_MAXIO_SIZE fscrypt_block_start(INT_MAX)
+
 static inline uint64_t fscrypt_align_ofs(uint64_t ofs) {
   return (ofs + FSCRYPT_DATA_ALIGNMENT - 1) & ~(FSCRYPT_DATA_ALIGNMENT - 1);
 }