Merge branch 'pass-single-links-instead-of-csv' into 'main'

Pass individual links in create-symlinks hook instead of CSV filename

See merge request nvidia/container-toolkit/container-toolkit!394

cmd/nvidia-ctk/hook/create-symlinks/create-symlinks.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/discover/csv"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/oci"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
@@ -125,21 +126,18 @@ func (m command) run(c *cli.Context, cfg *config) error {
 	created := make(map[string]bool)
 	// candidates is a list of absolute paths to symlinks in a chain, or the final target of the chain.
 	for _, candidate := range candidates {
-		targets, err := m.Locate(candidate)
+		target, err := symlinks.Resolve(candidate)
 		if err != nil {
 			m.logger.Debugf("Skipping invalid link: %v", err)
 			continue
-		} else if len(targets) != 1 {
-			m.logger.Debugf("Unexepected number of targets: %v", targets)
-			continue
-		} else if targets[0] == candidate {
+		} else if target == candidate {
 			m.logger.Debugf("%v is not a symlink", candidate)
 			continue
 		}
 
-		err = m.createLink(created, cfg.hostRoot, containerRoot, targets[0], candidate)
+		err = m.createLink(created, cfg.hostRoot, containerRoot, target, candidate)
 		if err != nil {
-			m.logger.Warnf("Failed to create link %v: %v", []string{targets[0], candidate}, err)
+			m.logger.Warnf("Failed to create link %v: %v", []string{target, candidate}, err)
 		}
 	}
 

internal/discover/symlinks.go

@@ -21,12 +21,16 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/discover/csv"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks"
 	"github.com/sirupsen/logrus"
 )
 
-type symlinks struct {
+type symlinkHook struct {
 	None
 	logger        *logrus.Logger
+	driverRoot    string
 	nvidiaCTKPath string
 	csvFiles      []string
 	mountsFrom    Discover
@@ -34,7 +38,7 @@ type symlinks struct {
 
 // NewCreateSymlinksHook creates a discoverer for a hook that creates required symlinks in the container
 func NewCreateSymlinksHook(logger *logrus.Logger, csvFiles []string, mounts Discover, nvidiaCTKPath string) (Discover, error) {
-	d := symlinks{
+	d := symlinkHook{
 		logger:        logger,
 		nvidiaCTKPath: nvidiaCTKPath,
 		csvFiles:      csvFiles,
@@ -45,17 +49,17 @@ func NewCreateSymlinksHook(logger *logrus.Logger, csvFiles []string, mounts Disc
 }
 
 // Hooks returns a hook to create the symlinks from the required CSV files
-func (d symlinks) Hooks() ([]Hook, error) {
-	var args []string
-	for _, f := range d.csvFiles {
-		args = append(args, "--csv-filename", f)
-	}
-
-	links, err := d.getSpecificLinkArgs()
+func (d symlinkHook) Hooks() ([]Hook, error) {
+	specificLinks, err := d.getSpecificLinks()
 	if err != nil {
 		return nil, fmt.Errorf("failed to determine specific links: %v", err)
 	}
-	args = append(args, links...)
+
+	csvSymlinks := d.getCSVFileSymlinks()
+	var args []string
+	for _, link := range append(csvSymlinks, specificLinks...) {
+		args = append(args, "--link", link)
+	}
 
 	hook := CreateNvidiaCTKHook(
 		d.nvidiaCTKPath,
@@ -66,8 +70,8 @@ func (d symlinks) Hooks() ([]Hook, error) {
 	return []Hook{hook}, nil
 }
 
-// getSpecificLinkArgs returns the required specic links that need to be created
-func (d symlinks) getSpecificLinkArgs() ([]string, error) {
+// getSpecificLinks returns the required specic links that need to be created
+func (d symlinkHook) getSpecificLinks() ([]string, error) {
 	mounts, err := d.mountsFrom.Mounts()
 	if err != nil {
 		return nil, fmt.Errorf("failed to discover mounts for ldcache update: %v", err)
@@ -99,11 +103,60 @@ func (d symlinks) getSpecificLinkArgs() ([]string, error) {
 		if linkProcessed[link] {
 			continue
 		}
+		linkProcessed[link] = true
 
 		linkPath := filepath.Join(filepath.Dir(m.Path), link)
-		links = append(links, "--link", fmt.Sprintf("%v::%v", target, linkPath))
-		linkProcessed[link] = true
+		links = append(links, fmt.Sprintf("%v::%v", target, linkPath))
 	}
 
 	return links, nil
 }
+
+func (d symlinkHook) getCSVFileSymlinks() []string {
+	chainLocator := lookup.NewSymlinkChainLocator(d.logger, d.driverRoot)
+
+	var candidates []string
+	for _, file := range d.csvFiles {
+		mountSpecs, err := csv.NewCSVFileParser(d.logger, file).Parse()
+		if err != nil {
+			d.logger.Debugf("Skipping CSV file %v: %v", file, err)
+			continue
+		}
+
+		for _, ms := range mountSpecs {
+			if ms.Type != csv.MountSpecSym {
+				continue
+			}
+			targets, err := chainLocator.Locate(ms.Path)
+			if err != nil {
+				d.logger.Warnf("Failed to locate symlink %v", ms.Path)
+			}
+			candidates = append(candidates, targets...)
+		}
+	}
+
+	var links []string
+	created := make(map[string]bool)
+	// candidates is a list of absolute paths to symlinks in a chain, or the final target of the chain.
+	for _, candidate := range candidates {
+		target, err := symlinks.Resolve(candidate)
+		if err != nil {
+			d.logger.Debugf("Skipping invalid link: %v", err)
+			continue
+		} else if target == candidate {
+			d.logger.Debugf("%v is not a symlink", candidate)
+			continue
+		}
+
+		link := fmt.Sprintf("%v::%v", target, candidate)
+		if created[link] {
+			d.logger.Debugf("skipping duplicate link: %v", link)
+			continue
+		}
+		created[link] = true
+
+		links = append(links, link)
+	}
+
+	return links
+}

internal/ldcache/ldcache.go

@@ -29,6 +29,7 @@ import (
 	"syscall"
 	"unsafe"
 
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -288,16 +289,7 @@ func (c *ldcache) resolve(target string) (string, error) {
 
 	c.logger.Debugf("checking %v", string(name))
 
-	info, err := os.Lstat(name)
-	if err != nil {
-		return "", fmt.Errorf("failed to get file info: %v", info)
-	}
-	if info.Mode()&os.ModeSymlink == 0 {
-		c.logger.Debugf("Resolved regular file: %v", name)
-		return name, nil
-	}
-
-	link, err := os.Readlink(name)
+	link, err := symlinks.Resolve(name)
 	if err != nil {
 		return "", fmt.Errorf("failed to resolve symlink: %v", err)
 	}

internal/lookup/symlinks.go

@@ -18,9 +18,9 @@ package lookup
 
 import (
 	"fmt"
-	"os"
 	"path/filepath"
 
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks"
 	"github.com/sirupsen/logrus"
 )
 
@@ -74,16 +74,9 @@ func (p symlinkChain) Locate(pattern string) ([]string, error) {
 		}
 		found[candidate] = true
 
-		info, err := os.Lstat(candidate)
+		target, err := symlinks.Resolve(candidate)
 		if err != nil {
-			return nil, fmt.Errorf("failed to get file info: %v", info)
-		}
-		if info.Mode()&os.ModeSymlink == 0 {
-			continue
-		}
-		target, err := os.Readlink(candidate)
-		if err != nil {
-			return nil, fmt.Errorf("error checking symlink: %v", err)
+			return nil, fmt.Errorf("error resolving symlink: %v", err)
 		}
 
 		if !filepath.IsAbs(target) {

internal/lookup/symlinks/symlink.go

@@ -0,0 +1,35 @@
+/**
+# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package symlinks
+
+import (
+	"fmt"
+	"os"
+)
+
+// Resolve returns the link target of the specified filename or the filename if it is not a link.
+func Resolve(filename string) (string, error) {
+	info, err := os.Lstat(filename)
+	if err != nil {
+		return filename, fmt.Errorf("failed to get file info: %v", info)
+	}
+	if info.Mode()&os.ModeSymlink == 0 {
+		return filename, nil
+	}
+
+	return os.Readlink(filename)
+}

internal/modifier/csv.go

@@ -81,6 +81,9 @@ func NewCSVModifier(logger *logrus.Logger, cfg *config.Config, ociSpec oci.Spec)
 		tegra.WithNVIDIACTKPath(cfg.NVIDIACTKConfig.Path),
 		tegra.WithCSVFiles(csvFiles),
 	)
+	if err != nil {
+		return nil, fmt.Errorf("failed to construct discoverer: %v", err)
+	}
 
 	discoverModifier, err := NewModifierFromDiscoverer(logger, d)
 	if err != nil {